java-servlet的dopost中写了控制台输出，测试到不执行数据库工具类后的代码，也不报错，会输出数据访问成功，连接到这个servlet成功的。—

servlet的dopost中写了控制台输出，测试到不执行数据库工具类后的代码，也不报错，会输出数据访问成功，连接到这个servlet成功的。

        System.out.println("数据访问成功");
        String sql="select * from employee";
        DBUtil dbUtil = new DBUtil();

        List<Employee> employeeList=new ArrayList<Employee>();
        System.out.println("开始执行查询");

编辑于：2019.11.26 21:16 发布于：2019.11.26 20:04

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: 两学一做让我进步

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DBUtil dbUtil = new DBUtil();这里仅仅new实例化，后面没有看到有执行数据库相关的方法，是不是没有贴全代码？

发布于：2019.11.26 21:35

评论 2 |

| 已采纳

: Json-Huang

声望： 1805

: 两学一做让我进步 谢谢啦，其实是DBUtil里面加载配置没有找到，用测试类测试dbUtil这个对象是会有空指针异常的，ClassLoader classLoader = DBUtil.class.getClassLoader(); inputStream = classLoader.getResourceAsStream("db.properties"); properties.load(inputStream); Class.forName(properties.getProperty("driver"));配置写对就能执行了。非常感谢关心。; 4 个月之前回复

: 秦时明月之君临天下 代码太少了; 4 个月之前回复

: 插入链接

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org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1417) at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) at java.lang.Thread.run(Thread.java:748) 13:58:03.316 [http-nio-9000-exec-15] WARN o.s.w.s.m.m.a.ExceptionHandlerExceptionResolver - [logException,194] - Resolved [java.lang.ArithmeticException: / by zero]

这个 Bug 搞了一个星期了没弄好,崩溃中,哪位大佬能帮忙看看??: 控制台信息:![图片说明](https://img-ask.csdn.net/upload/202001/18/1579336366_42087.jpg) ``` org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.mybatis.spring.MyBatisSystemException: nested exception is org.apache.ibatis.exceptions.PersistenceException: ### Error querying database. Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is org.apache.commons.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (Access denied for user 'koison'@'localhost' (using password: YES)) ### The error may exist in file [/Users/koison/IdeaProjects/selfOA/target/oasys/WEB-INF/classes/mapper/UserDao.xml] ### The error may involve com.gcc.dao.UserDao.findByUsername ### The error occurred while executing a query ### Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is org.apache.commons.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (Access denied for user 'koison'@'localhost' (using password: YES)) org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:982) org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:872) javax.servlet.http.HttpServlet.service(HttpServlet.java:660) org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846) javax.servlet.http.HttpServlet.service(HttpServlet.java:741) org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:81) org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:197) org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ```

在servlet中刚调用其他类的方法就报错: 控制可以打印“开始转换。。。”，但是执行下一句马上就抛出类未找到的异常，这个类是方法里面的一个类，但是根本就没有进入doc2Html这个方法体中就抛出了异常，单独运行测试ToWord中的方法是可以的。 servlet： ``` protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { ...... try{ ...... System.out.println("开始转换。。。"); resultFile= ToWord.doc2Html("F:/upload/"+filename, "F:/change"); } } }catch (Exception e) { message= "文件上传失败！"; e.printStackTrace(); } } ``` ToWord.class ``` public class ToWord（）{ doc2Html(){ ...... System.out.println("连接中。。。"); OpenOfficeConnection connection = new SocketOpenOfficeConnection(soffice_host, Integer.parseInt(soffice_port)); System.out.println("连接："+connection); ...... } } ``` 控制台：开始转换。。。六月 28, 2017 11:38:13 上午 org.apache.catalina.core.StandardWrapperValve invoke 严重: Servlet.service() for servlet [UploadServlet] in context with path [/TestIOStream] threw exception [Servlet execution threw an exception] with root cause java.lang.ClassNotFoundException: com.artofsolving.jodconverter.openoffice.connection.OpenOfficeConnection at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1892) at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1735) at com.fdauto.servlet.UploadServlet.doGet(UploadServlet.java:99) at com.fdauto.servlet.UploadServlet.doPost(UploadServlet.java:116) at javax.servlet.http.HttpServlet.service(HttpServlet.java:650) at javax.servlet.http.HttpServlet.service(HttpServlet.java:731) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:218) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:110) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:506) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:169) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103) at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:962) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:445) at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1115) at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:637) at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:318) at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) at java.lang.Thread.run(Unknown Source)

为什么这个servlet一直在报错: 一个很简单的验证登录的web ![图片说明](https://img-ask.csdn.net/upload/201610/16/1476621179_550097.png) 一直报错错误的行数显示如下: ![图片说明](https://img-ask.csdn.net/upload/201610/16/1476621206_114864.png) ![图片说明](https://img-ask.csdn.net/upload/201610/16/1476621218_338441.png) ![图片说明](https://img-ask.csdn.net/upload/201610/16/1476621226_98963.png) 可是我在测试类控制台中运行是没问题的如下: ![图片说明](https://img-ask.csdn.net/upload/201610/16/1476621313_820382.png) 而在servlet的doPost中就出现了问题: ![图片说明](https://img-ask.csdn.net/upload/201610/16/1476621356_153604.png) servlet配置和表单如下: ![图片说明](https://img-ask.csdn.net/upload/201610/16/1476621381_192849.png) ![图片说明](https://img-ask.csdn.net/upload/201610/16/1476621388_74954.png) 是我的Servlet哪里写错了吗求解决

JAVA导出Excel时，可以正常导出，但是后端控制台报错JsonMappingException: JAVA导出Excel时，可以正常导出，但是后端控制台报错JsonMappingException 具体报错代码如下 ``` 2019-11-29 10:24:49.693 ERROR [http-nio-9040-exec-3] [CommonResponseWrappedMsgFormater.java : 104] - 请求服务响应数据序列化输出异常： com.fasterxml.jackson.databind.JsonMappingException: No serializer found for class java.io.ByteArrayInputStream and no properties discovered to create BeanSerializer (to avoid exception, disable SerializationFeature.FAIL_ON_EMPTY_BEANS) (through reference chain: com.xmcares.framework.common.response.CommonResponse["data"]->org.apache.poi.xssf.usermodel.XSSFWorkbook["packagePart"]->org.apache.poi.openxml4j.opc.ZipPackagePart["zipArchive"]->org.apache.poi.openxml4j.util.ZipInputStreamZipEntrySource$FakeZipEntry["inputStream"]) at com.fasterxml.jackson.databind.JsonMappingException.from(JsonMappingException.java:284) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.SerializerProvider.mappingException(SerializerProvider.java:1110) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.SerializerProvider.reportMappingProblem(SerializerProvider.java:1135) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.ser.impl.UnknownSerializer.failForEmpty(UnknownSerializer.java:69) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.ser.impl.UnknownSerializer.serialize(UnknownSerializer.java:32) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:704) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:690) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.ser.BeanSerializer.serialize(BeanSerializer.java:155) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:704) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:690) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.ser.BeanSerializer.serialize(BeanSerializer.java:155) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:704) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:690) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.ser.BeanSerializer.serialize(BeanSerializer.java:155) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:704) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:690) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.ser.BeanSerializer.serialize(BeanSerializer.java:155) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.ser.DefaultSerializerProvider.serializeValue(DefaultSerializerProvider.java:292) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.ObjectMapper._configAndWriteValue(ObjectMapper.java:3681) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.ObjectMapper.writeValue(ObjectMapper.java:3014) ~[jackson-databind-2.8.8.jar:2.8.8] at com.xmcares.framework.serviceful.servlet.fomater.CommonResponseWrappedMsgFormater.formatMsgInternal(CommonResponseWrappedMsgFormater.java:102) [xcf-foundation-security-2.7.0.7-20191111.084436-3.jar:2.7.0.7-SNAPSHOT] at com.xmcares.framework.serviceful.servlet.fomater.CommonResponseWrappedMsgFormater.formatMsg(CommonResponseWrappedMsgFormater.java:69) [xcf-foundation-security-2.7.0.7-20191111.084436-3.jar:2.7.0.7-SNAPSHOT] at com.xmcares.framework.serviceful.servlet.ServletServiceResponseMarshaller.marshaller(ServletServiceResponseMarshaller.java:34) [xcf-foundation-security-2.7.0.7-20191111.084436-3.jar:2.7.0.7-SNAPSHOT] at com.xmcares.framework.serviceful.servlet.ServletServiceResponseMarshaller.marshaller(ServletServiceResponseMarshaller.java:24) [xcf-foundation-security-2.7.0.7-20191111.084436-3.jar:2.7.0.7-SNAPSHOT] at com.xmcares.framework.serviceful.ServicefulRouterAdapter.marshallerServiceResponse(ServicefulRouterAdapter.java:204) [xcf-foundation-security-2.7.0.7-20191111.084436-3.jar:2.7.0.7-SNAPSHOT] at com.xmcares.framework.serviceful.ServicefulRouterAdapter.route(ServicefulRouterAdapter.java:110) [xcf-foundation-security-2.7.0.7-20191111.084436-3.jar:2.7.0.7-SNAPSHOT] at com.xmcares.framework.serviceful.servlet.ServletServicefulRouter.route(ServletServicefulRouter.java:42) [xcf-foundation-security-2.7.0.7-20191111.084436-3.jar:2.7.0.7-SNAPSHOT] at com.xmcares.framework.serviceful.servlet.ServicefulServlet.doService(ServicefulServlet.java:112) [xcf-foundation-security-2.7.0.7-20191111.084436-3.jar:2.7.0.7-SNAPSHOT] at com.xmcares.framework.serviceful.servlet.AbstractHttpServlet.doPost(AbstractHttpServlet.java:55) [xcf-foundation-security-2.7.0.7-20191111.084436-3.jar:2.7.0.7-SNAPSHOT] at javax.servlet.http.HttpServlet.service(HttpServlet.java:661) [tomcat-embed-core-8.5.13.jar:8.5.13] at javax.servlet.http.HttpServlet.service(HttpServlet.java:742) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:230) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) [tomcat-embed-websocket-8.5.13.jar:8.5.13] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.springframework.boot.web.filter.ApplicationContextHeaderFilter.doFilterInternal(ApplicationContextHeaderFilter.java:55) [spring-boot-1.4.6.RELEASE.jar:1.4.6.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:101) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.13.jar:8.5.13] at com.xmcares.framework.security.author.UserContextHolderFilter.doFilter(UserContextHolderFilter.java:43) [xcf-foundation-security-2.7.0.7-20191111.084436-3.jar:2.7.0.7-SNAPSHOT] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.13.jar:8.5.13] at com.xmcares.framework.security.authen.AuthenticationPageFilter.doFilter(AuthenticationPageFilter.java:54) [xcf-foundation-security-2.7.0.7-20191111.084436-3.jar:2.7.0.7-SNAPSHOT] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:200) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:101) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.springframework.boot.actuate.trace.WebRequestTraceFilter.doFilterInternal(WebRequestTraceFilter.java:105) [spring-boot-actuator-1.4.6.RELEASE.jar:1.4.6.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:317) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:127) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:91) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:114) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:137) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:111) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:170) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:63) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:200) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at com.xmcares.framework.security.authen.AuthenticationPageFilter.doFilter(AuthenticationPageFilter.java:54) [xcf-foundation-security-2.7.0.7-20191111.084436-3.jar:2.7.0.7-SNAPSHOT] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at com.xmcares.framework.security.authen.CaptchaRequestFilter.doFilter(CaptchaRequestFilter.java:50) [xcf-foundation-security-2.7.0.7-20191111.084436-3.jar:2.7.0.7-SNAPSHOT] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:116) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.web.filter.CorsFilter.doFilterInternal(CorsFilter.java:96) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.header.HeaderWriterFilter.doFilterInternal(HeaderWriterFilter.java:64) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at com.xmcares.framework.security.author.UserContextHolderFilter.doFilter(UserContextHolderFilter.java:57) [xcf-foundation-security-2.7.0.7-20191111.084436-3.jar:2.7.0.7-SNAPSHOT] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:105) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter.doFilterInternal(WebAsyncManagerIntegrationFilter.java:56) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:214) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:177) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:346) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:262) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.springframework.web.filter.HttpPutFormContentFilter.doFilterInternal(HttpPutFormContentFilter.java:105) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:81) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.springframework.session.web.http.SessionRepositoryFilter.doFilterInternal(SessionRepositoryFilter.java:167) [spring-session-1.3.1.RELEASE.jar:na] at org.springframework.session.web.http.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:80) [spring-session-1.3.1.RELEASE.jar:na] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:197) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.springframework.boot.actuate.autoconfigure.MetricsFilter.doFilterInternal(MetricsFilter.java:106) [spring-boot-actuator-1.4.6.RELEASE.jar:1.4.6.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:478) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:80) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:341) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:799) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:861) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1455) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-embed-core-8.5.13.jar:8.5.13] at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [na:1.8.0_191] at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [na:1.8.0_191] at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-8.5.13.jar:8.5.13] at java.lang.Thread.run(Thread.java:748) [na:1.8.0_191] 2019-11-29 10:24:49.703 ERROR [http-nio-9040-exec-3] [ServicefulServlet.java : 114] - 服务化路由器执行请求/sysUser/downloadTemplate异常 com.xmcares.framework.serviceful.error.ServicefulException: 请求服务响应数据序列化输出异常 at com.xmcares.framework.serviceful.servlet.fomater.CommonResponseWrappedMsgFormater.formatMsgInternal(CommonResponseWrappedMsgFormater.java:105) ~[xcf-foundation-security-2.7.0.7-20191111.084436-3.jar:2.7.0.7-SNAPSHOT] at com.xmcares.framework.serviceful.servlet.fomater.CommonResponseWrappedMsgFormater.formatMsg(CommonResponseWrappedMsgFormater.java:69) ~[xcf-foundation-security-2.7.0.7-20191111.084436-3.jar:2.7.0.7-SNAPSHOT] at com.xmcares.framework.serviceful.servlet.ServletServiceResponseMarshaller.marshaller(ServletServiceResponseMarshaller.java:34) ~[xcf-foundation-security-2.7.0.7-20191111.084436-3.jar:2.7.0.7-SNAPSHOT] at com.xmcares.framework.serviceful.servlet.ServletServiceResponseMarshaller.marshaller(ServletServiceResponseMarshaller.java:24) ~[xcf-foundation-security-2.7.0.7-20191111.084436-3.jar:2.7.0.7-SNAPSHOT] at com.xmcares.framework.serviceful.ServicefulRouterAdapter.marshallerServiceResponse(ServicefulRouterAdapter.java:204) ~[xcf-foundation-security-2.7.0.7-20191111.084436-3.jar:2.7.0.7-SNAPSHOT] at com.xmcares.framework.serviceful.ServicefulRouterAdapter.route(ServicefulRouterAdapter.java:110) ~[xcf-foundation-security-2.7.0.7-20191111.084436-3.jar:2.7.0.7-SNAPSHOT] at com.xmcares.framework.serviceful.servlet.ServletServicefulRouter.route(ServletServicefulRouter.java:42) ~[xcf-foundation-security-2.7.0.7-20191111.084436-3.jar:2.7.0.7-SNAPSHOT] at com.xmcares.framework.serviceful.servlet.ServicefulServlet.doService(ServicefulServlet.java:112) ~[xcf-foundation-security-2.7.0.7-20191111.084436-3.jar:2.7.0.7-SNAPSHOT] at com.xmcares.framework.serviceful.servlet.AbstractHttpServlet.doPost(AbstractHttpServlet.java:55) [xcf-foundation-security-2.7.0.7-20191111.084436-3.jar:2.7.0.7-SNAPSHOT] at javax.servlet.http.HttpServlet.service(HttpServlet.java:661) [tomcat-embed-core-8.5.13.jar:8.5.13] at javax.servlet.http.HttpServlet.service(HttpServlet.java:742) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:230) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) [tomcat-embed-websocket-8.5.13.jar:8.5.13] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.springframework.boot.web.filter.ApplicationContextHeaderFilter.doFilterInternal(ApplicationContextHeaderFilter.java:55) [spring-boot-1.4.6.RELEASE.jar:1.4.6.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:101) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.13.jar:8.5.13] at com.xmcares.framework.security.author.UserContextHolderFilter.doFilter(UserContextHolderFilter.java:43) [xcf-foundation-security-2.7.0.7-20191111.084436-3.jar:2.7.0.7-SNAPSHOT] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.13.jar:8.5.13] at com.xmcares.framework.security.authen.AuthenticationPageFilter.doFilter(AuthenticationPageFilter.java:54) [xcf-foundation-security-2.7.0.7-20191111.084436-3.jar:2.7.0.7-SNAPSHOT] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:200) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:101) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.springframework.boot.actuate.trace.WebRequestTraceFilter.doFilterInternal(WebRequestTraceFilter.java:105) [spring-boot-actuator-1.4.6.RELEASE.jar:1.4.6.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:317) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:127) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:91) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:114) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:137) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:111) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:170) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:63) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:200) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at com.xmcares.framework.security.authen.AuthenticationPageFilter.doFilter(AuthenticationPageFilter.java:54) [xcf-foundation-security-2.7.0.7-20191111.084436-3.jar:2.7.0.7-SNAPSHOT] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at com.xmcares.framework.security.authen.CaptchaRequestFilter.doFilter(CaptchaRequestFilter.java:50) [xcf-foundation-security-2.7.0.7-20191111.084436-3.jar:2.7.0.7-SNAPSHOT] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:116) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.web.filter.CorsFilter.doFilterInternal(CorsFilter.java:96) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.header.HeaderWriterFilter.doFilterInternal(HeaderWriterFilter.java:64) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at com.xmcares.framework.security.author.UserContextHolderFilter.doFilter(UserContextHolderFilter.java:57) [xcf-foundation-security-2.7.0.7-20191111.084436-3.jar:2.7.0.7-SNAPSHOT] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:105) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter.doFilterInternal(WebAsyncManagerIntegrationFilter.java:56) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:214) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:177) [spring-security-web-4.2.0.RELEASE.jar:4.2.0.RELEASE] at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:346) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:262) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.springframework.web.filter.HttpPutFormContentFilter.doFilterInternal(HttpPutFormContentFilter.java:105) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:81) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.springframework.session.web.http.SessionRepositoryFilter.doFilterInternal(SessionRepositoryFilter.java:167) [spring-session-1.3.1.RELEASE.jar:na] at org.springframework.session.web.http.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:80) [spring-session-1.3.1.RELEASE.jar:na] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:197) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.springframework.boot.actuate.autoconfigure.MetricsFilter.doFilterInternal(MetricsFilter.java:106) [spring-boot-actuator-1.4.6.RELEASE.jar:1.4.6.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:478) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:80) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:341) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:799) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:861) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1455) [tomcat-embed-core-8.5.13.jar:8.5.13] at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-embed-core-8.5.13.jar:8.5.13] at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [na:1.8.0_191] at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [na:1.8.0_191] at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-8.5.13.jar:8.5.13] at java.lang.Thread.run(Thread.java:748) [na:1.8.0_191] Caused by: com.fasterxml.jackson.databind.JsonMappingException: No serializer found for class java.io.ByteArrayInputStream and no properties discovered to create BeanSerializer (to avoid exception, disable SerializationFeature.FAIL_ON_EMPTY_BEANS) (through reference chain: com.xmcares.framework.common.response.CommonResponse["data"]->org.apache.poi.xssf.usermodel.XSSFWorkbook["packagePart"]->org.apache.poi.openxml4j.opc.ZipPackagePart["zipArchive"]->org.apache.poi.openxml4j.util.ZipInputStreamZipEntrySource$FakeZipEntry["inputStream"]) at com.fasterxml.jackson.databind.JsonMappingException.from(JsonMappingException.java:284) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.SerializerProvider.mappingException(SerializerProvider.java:1110) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.SerializerProvider.reportMappingProblem(SerializerProvider.java:1135) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.ser.impl.UnknownSerializer.failForEmpty(UnknownSerializer.java:69) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.ser.impl.UnknownSerializer.serialize(UnknownSerializer.java:32) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:704) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:690) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.ser.BeanSerializer.serialize(BeanSerializer.java:155) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:704) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:690) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.ser.BeanSerializer.serialize(BeanSerializer.java:155) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:704) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:690) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.ser.BeanSerializer.serialize(BeanSerializer.java:155) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:704) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:690) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.ser.BeanSerializer.serialize(BeanSerializer.java:155) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.ser.DefaultSerializerProvider.serializeValue(DefaultSerializerProvider.java:292) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.ObjectMapper._configAndWriteValue(ObjectMapper.java:3681) ~[jackson-databind-2.8.8.jar:2.8.8] at com.fasterxml.jackson.databind.ObjectMapper.writeValue(ObjectMapper.java:3014) ~[jackson-databind-2.8.8.jar:2.8.8] at com.xmcares.framework.serviceful.servlet.fomater.CommonResponseWrappedMsgFormater.formatMsgInternal(CommonResponseWrappedMsgFormater.java:102) ~[xcf-foundation-security-2.7.0.7-20191111.084436-3.jar:2.7.0.7-SNAPSHOT] ... 118 common frames omitted ```

web.xml的配置好像不对，运行项目控制台总是报错说找不到类，是不是路径错了: LoginAction.java: package campsg.qunawan.action; import java.io.IOException; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.apache.catalina.mbeans.UserMBean; public class LoginAction extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { System.out.println("执行LoginAction方法"); doPost(request,response); } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String method = request.getParameter("method"); if("login".equals(method)){//登录 String username = request.getParameter("username"); String password = request.getParameter("password"); if(username==null||"".equals(username.trim())||password==null||"".equals(password.trim())){ System.out.println("用户名或密码不能为空！"); response.sendRedirect("login.html"); return; } boolean isValid = false; if(isValid){ System.out.println("登录成功！"); request.getSession().setAttribute("username", username); response.sendRedirect("index.html"); return; }else{ System.out.println("用户名或密码错误，登录失败！"); response.sendRedirect("login.html"); return; } }else if("logout".equals(method)){//退出登录 System.out.println("退出登录！"); request.getSession().removeAttribute("username"); response.sendRedirect("login.html"); return; } } } ![图片说明](https://img-ask.csdn.net/upload/201612/16/1481849480_663914.png) ![图片说明](https://img-ask.csdn.net/upload/201612/16/1481849494_867200.png) ![图片说明](https://img-ask.csdn.net/upload/201612/16/1481849783_238355.png)

两个servlet文件间通过post方法传一个自定义类的对象: 这是发送对象的servlet文件 package Test; import java.io.IOException; import java.io.ObjectOutputStream; import java.io.OutputStream; import java.io.PrintWriter; import java.net.HttpURLConnection; import java.net.URL; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; class TransferData{ int a; int b; int c; } public class myservlet extends HttpServlet { /** * Constructor of the object. */ public myservlet() { super(); } /** * Destruction of the servlet. <br> */ public void destroy() { super.destroy(); // Just puts "destroy" string in log // Put your code here } public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { /*response.setContentType("text/html"); PrintWriter out = response.getWriter(); out.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">"); out.println("<HTML>"); out.println(" <HEAD><TITLE>A Servlet</TITLE></HEAD>"); out.println(" <BODY>"); out.print(" This is "); out.print(this.getClass()); out.println(", using the GET method"); out.println("-------------"); String str=request.getParameter("max"); int max=Integer.parseInt(str); int sum=0; for(int i=1;i<=max;i++){ sum+=i; } out.println(sum); */ this.doPost(request, response);//service默认走的是doGet方法，调用doPost方法，才会走doPost,否则不走doPost方法 /* out.println(" </BODY>"); out.println("</HTML>"); out.flush(); out.close();*/ } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setContentType("text/html"); PrintWriter out = response.getWriter(); out.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">"); out.println("<HTML>"); out.println(" <HEAD><TITLE>A Servlet</TITLE></HEAD>"); out.println(" <BODY>"); out.print(" This is "); out.print(this.getClass()); out.println(", using the POST method"); String urlstr="http://xz-20140612mxua:8080/J2eeTest/test/getObject"; try{ URL url=new URL(urlstr); HttpURLConnection conn=(HttpURLConnection)url.openConnection(); conn.setDoOutput(true); conn.setRequestMethod("POST"); conn.setConnectTimeout(10000); conn.setReadTimeout(20000); conn.connect(); TransferData td=new TransferData(); out.println("--------------------0"); td.a=10; td.b=20; td.c=200; out.println("--------------------1"); OutputStream outputstream=conn.getOutputStream();//创建输出流，并把该输出流关联到创建的联系conn上 out.println("--------------------2"); ObjectOutputStream oos = new ObjectOutputStream(outputstream);//创建对象输出流 out.println("--------------------3"); out.println(td); oos.writeObject(td);//通过对象输出流输出对象?有问题控制台只能输出到-----3这里 out.println("--------------------4"); out.println(td.a); out.println("--------------------5"); }catch(Exception e){} out.println(" </BODY>"); out.println("</HTML>"); out.flush(); out.close(); } public void init() throws ServletException { // Put your code here } } 这是接受对象的servlet文件 package Test; import java.io.IOException; import java.io.InputStream; import java.io.ObjectInputStream; import java.io.PrintWriter; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; public class getObject extends HttpServlet { /** * Constructor of the object. */ public getObject() { super(); } /** * Destruction of the servlet. <br> */ public void destroy() { super.destroy(); // Just puts "destroy" string in log // Put your code here } /** * The doGet method of the servlet. <br> * * This method is called when a form has its tag value method equals to get. * * @param request the request send by the client to the server * @param response the response send by the server to the client * @throws ServletException if an error occurred * @throws IOException if an error occurred */ public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { /*response.setContentType("text/html"); PrintWriter out = response.getWriter(); out.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">"); out.println("<HTML>"); out.println(" <HEAD><TITLE>A Servlet</TITLE></HEAD>"); out.println(" <BODY>"); out.print(" This is "); out.print(this.getClass()); out.println(", using the GET method"); */ this.doPost(request,response); /* out.println(" </BODY>"); out.println("</HTML>"); out.flush(); out.close();*/ } /** * The doPost method of the servlet. <br> * * This method is called when a form has its tag value method equals to post. * * @param request the request send by the client to the server * @param response the response send by the server to the client * @throws ServletException if an error occurred * @throws IOException if an error occurred */ public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setContentType("text/html"); PrintWriter out = response.getWriter(); out.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">"); out.println("<HTML>"); out.println(" <HEAD><TITLE>A Servlet</TITLE></HEAD>"); out.println(" <BODY>"); out.print(" This is "); out.print(this.getClass()); out.println(", using the POST method"); out.println("--------------------0"); try{ InputStream in = request.getInputStream(); out.println("--------------------1"); ObjectInputStream ois = new ObjectInputStream(in);//?有问题 out.println("--------------------2"); TransferData td1 = (TransferData)(ois.readObject()); out.println("--------------------3"); System.out.println(td1.a); out.println("--------------------4"); System.out.println(td1.b); out.println("--------------------5"); System.out.println(td1.c); out.println("--------------------6"); }catch(Exception e){} out.println(" </BODY>"); out.println("</HTML>"); out.flush(); out.close(); } /** * Initialization of the servlet. <br> * * @throws ServletException if an error occurs */ public void init() throws ServletException { // Put your code here } } 困扰很久了，求大神帮解答，问题不解决，感觉后面的东西没法继续学。

请大佬们看看我上传图片到本地项目然后数据库保存路劲为null是那部分出错了？: 接收图片的jsp前端页面 ``` <form method="post" action="PicUpServlet" enctype="multipart/form-data"> <fieldset class="layui-elem-field layui-field-title" style="margin-top: 30px;"> <legend>添加文章</legend> </fieldset> <div class="layui-form-item layui-form-text" > <div class="layui-input-block" style="margin-left: 0px;"> <textarea placeholder="请输入内容" class="layui-textarea"></textarea> </div> </div>  <fieldset class="layui-elem-field layui-field-title" style="margin-top: 30px;" > <legend>添加图片</legend> </fieldset> <div style="margin-left: 8px;"> <input type="file" name="uploadFile"/> </div> <br/><br/> <div style="margin-left: 8px;"> <input type="submit" value="上传" /> </div> </form> ``` 文件保存 ``` package com.gugu.servlet; import java.io.File; import java.io.IOException; import java.util.Map; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import com.gugu.dao.WisUploadDao; import com.gugu.pojo.GgNote; import com.gugu.util.Upload; public class PicUpServlet extends HttpServlet { private static final long serialVersionUID = 1L; private static final String UPLOAD_DIRECTORY = "C:\\MyBlog-master\\WebContent\\images"; public PicUpServlet() { super(); } protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.getWriter().append("Served at: ").append(request.getContextPath()); } protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { request.setCharacterEncoding("UTF-8"); String path = UPLOAD_DIRECTORY+"//images//"+File.separator ; Map<String, String> map = Upload.upload(request, 1024 * 1024 * 10, path); String newFileName ="images"+File.separator+ map.get("newFileName"); GgNote note = new GgNote(); note.setNoteContent(map.get("content")); note.setNotePhoto(newFileName); System.out.println(newFileName); System.out.println(map.get("content")); WisUploadDao add = new WisUploadDao(); add.addwis(note); response.sendRedirect("page/whisper/manage.jsp"); } } ``` 判断文字还是图片 ``` package com.gugu.util; import java.io.File; import java.io.IOException; import java.util.Date; import java.util.HashMap; import java.util.Map; import javax.servlet.http.HttpServletRequest; import com.oreilly.servlet.multipart.FilePart; import com.oreilly.servlet.multipart.MultipartParser; import com.oreilly.servlet.multipart.ParamPart; import com.oreilly.servlet.multipart.Part; public class Upload { public static Map<String, String> upload(HttpServletRequest request,int maxSize, String path) { //以map形式保存数据 key对应保存的是获取界面上的name名称 value保存的是获取界面上的name对应的值 Map<String, String> map = new HashMap<String, String>(); Part part = null; try { MultipartParser mrequest = new MultipartParser(request, maxSize); mrequest.setEncoding("utf-8"); //遍历所有的part组 while ((part = mrequest.readNextPart()) != null) { if (part.isFile()) { //判断是否是文件 FilePart filepart = (FilePart) part;//转化成文件组 String fileName = filepart.getFileName();//得到文件名 if (fileName != null && fileName.length() > 0) { // 取得扩展名 String fileExtName = fileName.substring( fileName.lastIndexOf(".") + 1).toLowerCase(); // 只上传图片 //判断图片上传的格式是否符合后缀名是否有效 if (fileExtName.equalsIgnoreCase("jpeg") || fileExtName.equalsIgnoreCase("png") || fileExtName.equalsIgnoreCase("jpg") || fileExtName.equalsIgnoreCase("gif") || fileExtName.equalsIgnoreCase("ico") || fileExtName.equalsIgnoreCase("bmp") || fileExtName.equalsIgnoreCase("flv") || fileExtName.equalsIgnoreCase("mp4") || fileExtName.equalsIgnoreCase("mp3")) { /*String newFileName = new Date().getTime() + "."+ fileExtName;//重新改文件名文件名+扩展名 */ String newFileName =new Date().getTime() +fileName;//不改图片名字 String newPath = path + "/" + newFileName; //文件处理文件上传的路径 File newFile = new File(newPath); filepart.writeTo(newFile); //将文件真正写入到对应的文件夹中 //filepart.getName() 得到 request 要接收的参数的名字 map.put("newFileName", newFileName); map.put(filepart.getName(), newFileName);//把文件信息保存到map中 map.put("newFile", newFile.toString()); } else { map.put("geshi", "geshi"); continue; }// 说明上传的不是图片 } else { map.put("yes","yes"); continue; // 说明没有选择上传图片 } } else if (part.isParam()) { //判断是否是参数 ParamPart paramPart = (ParamPart) part; map.put(paramPart.getName(), paramPart.getStringValue()); } } } catch (IOException e) { e.printStackTrace(); } return map; } } ``` 上传到数据库的文字内容为null 图片保存路劲也为null请问是那部分出错了控制台报错 ``` java.io.FileNotFoundException: C:\Users\12874\Desktop\毕业设计\MyBlog-master\WebContent\images\images\1572883296157tony_tony_chopper-006.jpg (系统找不到指定的路径。) at java.io.FileOutputStream.open0(Native Method) at java.io.FileOutputStream.open(Unknown Source) at java.io.FileOutputStream.<init>(Unknown Source) at java.io.FileOutputStream.<init>(Unknown Source) at com.oreilly.servlet.multipart.FilePart.writeTo(FilePart.java:166) at com.gugu.util.Upload.upload(Upload.java:50) at com.gugu.servlet.PicUpServlet.doPost(PicUpServlet.java:40) at javax.servlet.http.HttpServlet.service(HttpServlet.java:660) at javax.servlet.http.HttpServlet.service(HttpServlet.java:741) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:202) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:526) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:678) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343) at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:408) at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:861) at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1579) at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) at java.lang.Thread.run(Unknown Source) images\null null ```

servlet中Gson转换Json数据为对象，获取对象属性时报空指针问题，求解答: 服务端获取的json字符串如下：{"name":"王五","course":{"chinese":70,"english":90}}；转化成student对象，代码如下： package sourceCode; import java.io.BufferedReader; import java.io.IOException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import com.google.gson.Gson; public class TestJson extends HttpServlet{ public void doPost(HttpServletRequest res,HttpServletResponse req) throws IOException{ req.setHeader("Content-Type", "application/json;charset=utf-8"); BufferedReader br = res.getReader(); StringBuffer sb = new StringBuffer(); String str; while((str=br.readLine())!=null){ sb.append(str); } String jsonStr = sb.toString(); System.out.println("sb为："+jsonStr); br.close(); Gson gson = new Gson(); Student stu = gson.fromJson(jsonStr, Student.class); System.out.println(stu.getName); System.out.println(stu.getCourse().getChinese()); } } student和sourse类代码如下： public class Student { private String name; private Course course; public Student() { super(); } public Student(String name, Course course) { super(); this.name = name; this.course = course; } //此处省略set和get函数 } public class Course { private int chinese; private int english; public Course() { super(); } public Course(int chinese, int english) { super(); this.chinese = chinese; this.english = english; } //此处省略set和get函数 } 当前台发起请求servlet时，控制台打印出的结果如下： ![图片说明](https://img-ask.csdn.net/upload/201803/18/1521382594_157346.png)

Dao执行了两遍导致数据查询结果不准确: 如题，我的Dao层代码如下（感觉没毛病......）： ``` public class MessageDao { public ArrayList<Message> queryMessageList(String command,String description){ ArrayList<Message> messageList = new ArrayList<Message>(); Message message = null; try { Class.forName("com.mysql.jdbc.Driver"); Connection conn = DriverManager.getConnection("jdbc:mysql://127.0.0.1:3306/micro_message","root","root"); StringBuilder sql = new StringBuilder("select ID,COMMAND,DESCRIPTION,CONTENT from message where 1=1 "); ArrayList<String> paramList = new ArrayList<String>(); if(command!=null && !command.trim().equals("")){ System.out.println("command不为空"); sql.append(" and COMMAND=? "); paramList.add(command); } if(description!=null && !description.trim().equals("")){ System.out.println("description不为空"); sql.append(" and DESCRIPTION LIKE '%' ? '%' "); paramList.add(description); } PreparedStatement statement = conn.prepareStatement(sql.toString()); for(int i=0;i<paramList.size();i++){ System.out.println(paramList.get(i)); statement.setString(i+1, paramList.get(i)); } ResultSet rs = statement.executeQuery(); while(rs.next()){ message = new Message(); message.setId(rs.getInt("ID")); message.setCommand(rs.getString("COMMAND")); message.setContent(rs.getString("CONTENT")); message.setDescription(rs.getString("DESCRIPTION")); messageList.add(message); } } catch (ClassNotFoundException e) { e.printStackTrace(); } catch (SQLException e) { e.printStackTrace(); } return messageList; } } ``` 然后执行查询后，网页上没有显示查询的信息，经过在控制台打印输出，查询的对象集合为空，如下截图： ![图片说明](https://img-ask.csdn.net/upload/201704/02/1491139012_229232.png) 上面打印了两次，但我只执行了一次（点击了一次查询按钮，问题应该在这里.....）各位大神，技术控能找到问题出在哪儿吗？？求赐教！！！下面是其他层相关代码供参考。 service层代码 ``` public class ListService { public ArrayList<Message> queryMessageList(String command,String description){ MessageDao messageDao = new MessageDao(); return messageDao.queryMessageList(command, description); } } ``` servlet代码： ``` protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { //设置编码，获取页面的值，向页面传值 request.setCharacterEncoding("utf-8"); String command = request.getParameter("command"); String description = request.getParameter("description"); request.setAttribute("command", command); request.setAttribute("description", description); //查询消息列表 ListService listService = new ListService(); request.setAttribute("messageList", listService.queryMessageList(command, description)); System.out.println(listService.queryMessageList(command, description)); //跳转 request.getRequestDispatcher("/WEB-INF/jsp/back/list.jsp").forward(request, response); } ``` jsp： ``` <form action="<%= basePath %>ListServlet" id="mainForm" method="post"> <div class="right"> <div class="current">当前位置：<a href="javascript:void(0)" style="color:#6E6E6E;">内容管理</a> > 内容列表</div> <div class="rightCont"> <p class="g_title fix">内容列表 <a class="btn03" href="#">新增</a>    <a class="btn03" href="#">删除</a></p> <table class="tab1"> <tbody> <tr> <td width="90" align="right">指令名称：</td> <td> <input type="text" name="command" class="allInput" value="${command}"/> </td> <td width="90" align="right">描述：</td> <td> <input type="text" name="description" class="allInput" value="${description}"/> </td> <td width="85" align="right"><input type="submit" class="tabSub" value="查询" /></td> </tr> </tbody> </table> ...... ```

Springmvc上传文件限制大小，异常处理返回报错信息后，eclipse控制台还报错: **1、web.xml配置:** ``` <?xml version="1.0" encoding="UTF-8"?> <web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">  <servlet> <servlet-name>DispatcherServlet</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>  <init-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:applicationContext.xml</param-value> </init-param> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>DispatcherServlet</servlet-name> <url-pattern>*.from</url-pattern> </servlet-mapping>  <filter> <filter-name>encodingFilter</filter-name> <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class> <init-param> <param-name>encoding</param-name> <param-value>UTF-8</param-value> </init-param> </filter> <filter-mapping> <filter-name>encodingFilter</filter-name> <url-pattern>/*</url-pattern> </filter-mapping> </web-app> ``` **spring的applicationContext.xml配置：** ``` <?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context" xmlns:jdbc="http://www.springframework.org/schema/jdbc" xmlns:jee="http://www.springframework.org/schema/jee" xmlns:tx="http://www.springframework.org/schema/tx" xmlns:jpa="http://www.springframework.org/schema/data/jpa" xmlns:util="http://www.springframework.org/schema/util" xmlns:mvc="http://www.springframework.org/schema/mvc" xsi:schemaLocation=" http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.2.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.2.xsd http://www.springframework.org/schema/jdbc http://www.springframework.org/schema/jdbc/spring-jdbc-3.2.xsd http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee-3.2.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.2.xsd http://www.springframework.org/schema/data/jpa http://www.springframework.org/schema/data/jpa/spring-jpa-1.3.xsd http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-3.2.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.2.xsd">  <context:component-scan base-package="controller"></context:component-scan>  <mvc:annotation-driven></mvc:annotation-driven>  <bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <property name="prefix"> <value>/WEB-INF/jsp/</value> </property> <property name="suffix"> <value>.jsp</value> </property> </bean>  <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver"> <property name="maxUploadSize" value="10240"></property> <property name="resolveLazily" value="true"></property> </bean> </beans> ``` **java代码Controller处理：** ``` package controller; import java.io.File; import java.util.HashMap; import java.util.Map; import javax.servlet.http.HttpServletRequest; import org.springframework.stereotype.Controller; import org.springframework.ui.ModelMap; import org.springframework.web.bind.annotation.ExceptionHandler; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RequestParam; import org.springframework.web.multipart.MaxUploadSizeExceededException; import org.springframework.web.multipart.MultipartFile; import org.springframework.web.servlet.ModelAndView; @Controller public class UploadController { // 访问upload.jsp页面 @RequestMapping("/toUpload") public String toUpload() { return "upload"; } @RequestMapping("/upload") public String upload(@RequestParam("file") MultipartFile file, HttpServletRequest request, ModelMap model) throws Exception { // 判断提交来的文件是否为空 if (file.isEmpty()) { // model.addAttribute("error", "上传文件不能为空"); // return "upload"; throw new RuntimeException("file is null"); } // 获取文件所要保存目录在服务器上所对应的实际路径 String path = request.getSession().getServletContext().getRealPath( "upload"); System.out.println(path); // 组成拥有真实路径的一个完整的地址字符串 String fileUrl = path + "\\" + file.getOriginalFilename(); // 封装上传文件名称到model对象中 model.addAttribute("fileName", file.getOriginalFilename()); // 根据这个完整地址字符串，生成提交文件所要保存到的目标文件或目录的对象 File targetFile = new File(fileUrl); // 判断目标文件或目录的对象是否已经存在 if (!targetFile.exists()) { targetFile.mkdirs(); } // 传送文件到目标对象 file.transferTo(targetFile); System.out.println("已上传文件：" + file); return "ok"; } @ExceptionHandler public ModelAndView doException(Exception e,HttpServletRequest request) throws Exception { Map<String,Object> map = new HashMap<String,Object>(); if (e instanceof MaxUploadSizeExceededException) { long maxSize = ((MaxUploadSizeExceededException) e) .getMaxUploadSize(); map.put("error", "上传文件太大，不能超过" + maxSize / 1024 + "k"); }else if(e instanceof RuntimeException){ map.put("error", "未选中文件"); }else{ map.put("error", "上传失败"); } return new ModelAndView("upload",map); } } ``` **上传文件页面upload.jsp：** ``` <%@ page pageEncoding="UTF-8" contentType="text/html;charset=UTF-8"%> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <title>上传页面</title> </head> <body> <form action="upload.from" method="post" enctype="multipart/form-data"> <input type="file" name="file"/> <input type="submit" value="上传"/><font color="red">${error}</font> </form> </body> </html> ``` **上传成功页面ok.jsp：** ``` <%@ page pageEncoding="UTF-8" contentType="text/html;charset=UTF-8"%> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <title>ok.jsp</title> </head> <body> <h1>上传成功</h1> <a href="upload/${fileName}">${fileName}</a> </body> </html> ``` **eclipse控制台报错信息如下：** ``` 五月 01, 2015 10:27:01 下午 org.springframework.web.multipart.commons.CommonsMultipartResolver cleanupMultipart 警告: Failed to perform multipart cleanup for servlet request org.springframework.web.multipart.MaxUploadSizeExceededException: Maximum upload size of 10240 bytes exceeded; nested exception is org.apache.commons.fileupload.FileUploadBase$SizeLimitExceededException: the request was rejected because its size (19243) exceeds the configured maximum (10240) at org.springframework.web.multipart.commons.CommonsMultipartResolver.parseRequest(CommonsMultipartResolver.java:160) at org.springframework.web.multipart.commons.CommonsMultipartResolver$1.initializeMultipart(CommonsMultipartResolver.java:131) at org.springframework.web.multipart.support.AbstractMultipartHttpServletRequest.getMultipartFiles(AbstractMultipartHttpServletRequest.java:119) at org.springframework.web.multipart.support.AbstractMultipartHttpServletRequest.getMultiFileMap(AbstractMultipartHttpServletRequest.java:99) at org.springframework.web.multipart.commons.CommonsMultipartResolver.cleanupMultipart(CommonsMultipartResolver.java:188) at org.springframework.web.servlet.DispatcherServlet.cleanupMultipart(DispatcherServlet.java:1062) at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:955) at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:856) at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:953) at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:855) at javax.servlet.http.HttpServlet.service(HttpServlet.java:650) at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:829) at javax.servlet.http.HttpServlet.service(HttpServlet.java:731) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:505) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:170) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103) at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:423) at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1079) at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:620) at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.doRun(AprEndpoint.java:2476) at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.run(AprEndpoint.java:2465) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) at java.lang.Thread.run(Thread.java:745) Caused by: org.apache.commons.fileupload.FileUploadBase$SizeLimitExceededException: the request was rejected because its size (19243) exceeds the configured maximum (10240) at org.apache.commons.fileupload.FileUploadBase$FileItemIteratorImpl.<init>(FileUploadBase.java:914) at org.apache.commons.fileupload.FileUploadBase.getItemIterator(FileUploadBase.java:331) at org.apache.commons.fileupload.FileUploadBase.parseRequest(FileUploadBase.java:349) at org.apache.commons.fileupload.servlet.ServletFileUpload.parseRequest(ServletFileUpload.java:126) at org.springframework.web.multipart.commons.CommonsMultipartResolver.parseRequest(CommonsMultipartResolver.java:156) ... 37 more ``` 上传文件超过限制大小，异常处理后页面返回了提示信息“上传文件太大，不能超过10k”，但是为啥eclipse的控制台还是有报错呢？

表单重复提交的问题，谷歌——开发者工具: ``` <form action="<%= path%>/servlet/TestServlet" method="post"> username:<input type="text" name="username"> <input type="submit" value="submit"> </form> ``` ``` public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { try { Thread.sleep(2000); } catch (InterruptedException e) { e.printStackTrace(); } System.out.println("***************"); String username = request.getParameter("username"); response.getWriter().println(username+":"+i++); } ``` 因为让servlet先睡2秒，所以我点击了多次submit提交。 ![图片说明](https://img-ask.csdn.net/upload/201509/18/1442571630_53710.jpg) 如图:谷歌——开发者工具图中问题，求助。 servlet能在控制台输出多次信息，说明这多次请求都得到的响应。那个canceled不太懂什么意思。是前面的响应页面的内容被最后一次提交的响应给刷新掉导致的吗？？

java web 连接数据库的问题: 程序突然就连不上数据库了，之前一直好好的，把登陆部分的代码贴上来，求大神给看看 jsp部分：<!DOCTYPE html>      <html lang="en" class="no-js">  <head> <meta charset="UTF-8" />  <meta name="viewport" content="width=device-width, initial-scale=1.0"> <meta name="description" content="Login and Registration Form with HTML5 and CSS3" /> <meta name="keywords" content="html5, css3, form, switch, animation, :target, pseudo-class" /> <meta name="author" content="Codrops" /> <link rel="shortcut icon" href="../favicon.ico"> <link rel="stylesheet" type="text/css" href="css/demo.css" /> <link rel="stylesheet" type="text/css" href="css/style.css" /> <link rel="stylesheet" type="text/css" href="css/animate-custom.css" /> </head> <body> <div class="container">  <div class="codrops-top"> <div class="clr"></div> </div> <header> <nav class="codrops-demos"> </nav> </header> <section> <div id="container_demo" >  <a class="hiddenanchor" id="toregister"></a> <a class="hiddenanchor" id="tologin"></a> <div id="wrapper"> <div id="login" class="animate form"> <form action="com.xx.servlet/LoginServlet" method="post"> <h1>Log in</h1> <p> <label for="username" class="uname" data-icon="u" > Your username </label> <input type="text" name="username" /> </p> <p> <label for="password" class="youpasswd" data-icon="p"> Your password </label> <input type="password" name="password" /> </p> <p class="keeplogin"> </p> <p class="login button"> <input type="submit" value="Login" /> </p> <p class="change_link"> Not a member yet ? <a href="register.jsp" class="to_register">Join us</a> </p> </div> </div> </div> </section> </div> </body> </html> servlet部分：package com.xx.servlet; import java.io.IOException; import java.sql.Connection; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import javax.naming.spi.DirStateFactory.Result; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import javax.servlet.http.HttpSession; import com.bbs.*; import com.mysql.jdbc.Driver; /** * Servlet implementation class LoginServlet */ @WebServlet("/LoginServlet") public class LoginServlet extends HttpServlet { private static final long serialVersionUID = 1L; /** * @see HttpServlet#HttpServlet() */ public LoginServlet() { super(); // TODO Auto-generated constructor stub } /** * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response) */ protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doPost(request, response);// TODO Auto-generated method stub } /** * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response) */ protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setCharacterEncoding("utf-8"); response.setContentType("text/html;charset=utf-8"); request.setCharacterEncoding("utf-8"); String name = null;String level = null; Connection conn = null; Statement stmt=null; ResultSet res=null; boolean flag=false;//通过数据库匹配标识 String name_checked=null;//检查通过的用户名 try { Class.forName("com.mysql.jdbc.Driver"); } catch (ClassNotFoundException e) { // TODO 自动生成的 catch 块 e.printStackTrace(); } String URL="jdbc:mysql://localhost:3306/mybbs"; String USER="root"; String PASSWORD="5438027"; //1.加载驱动程序 try { Class.forName("com.mysql.jdbc.Driver"); } catch (ClassNotFoundException e1) { System.out.println("加载驱动失败1");// TODO 自动生成的 catch 块 e1.printStackTrace(); } //2.获得数据库的链接 try { DriverManager.registerDriver(new Driver()); conn=DriverManager.getConnection(URL, USER, PASSWORD); } catch (SQLException e) { System.out.println("加载失败2");// TODO 自动生成的 catch 块 e.printStackTrace(); } String u=request.getParameter("username"); //从上级页面获得用户名 String p=request.getParameter("password"); //从上级页面获得密码 String sql="SELECT * FROM user WHERE userName IN('"+u+"') "+"AND passWord IN('"+p+"')"; System.out.println(sql);//执行上述sql语句 try { res=stmt.executeQuery(sql); } catch (SQLException e) { System.out.println("加载失败3");// TODO 自动生成的 catch 块 e.printStackTrace(); } try { if(true==res.next())//只有查询得到结果才可进入循环 { flag=true; name_checked=res.getString("name"); level=res.getString("level"); } } catch (SQLException e) { System.out.println("加载失败4");// TODO 自动生成的 catch 块 e.printStackTrace(); } if(true==flag)//登陆成功 { HttpSession session=request.getSession(); session.setAttribute("userlevel",level); session.setAttribute("name",name_checked); response.sendRedirect(request.getContextPath()+"/loginsuccess.jsp"); User me=new User(); } else//登陆失败 { response.sendRedirect(request.getContextPath()+"/login.jsp"); } } } 报错：HTTP Status 500 - type Exception report message description The server encountered an internal error that prevented it from fulfilling this request. exception java.lang.NullPointerException com.xx.servlet.LoginServlet.doPost(LoginServlet.java:99) javax.servlet.http.HttpServlet.service(HttpServlet.java:650) javax.servlet.http.HttpServlet.service(HttpServlet.java:731) org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) note The full stack trace of the root cause is available in the Apache Tomcat/7.0.82 logs. Apache Tomcat/7.0.82 控制台:十月 26, 2017 1:10:55 上午 org.apache.catalina.core.StandardWrapperValve invoke 严重: Servlet.service() for servlet [LoginServlet] in context with path [/xxbbs] threw exception java.lang.NullPointerException at com.xx.servlet.LoginServlet.doPost(LoginServlet.java:99) at javax.servlet.http.HttpServlet.service(HttpServlet.java:650) at javax.servlet.http.HttpServlet.service(HttpServlet.java:731) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:219) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:110) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:506) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:169) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103) at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:962) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:445) at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1115) at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:637) at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:318) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) at java.lang.Thread.run(Thread.java:744) 不知道哪里出问题了，之前一直好好的，求大神帮我看看

用dubbo调用三方接口报错，但是不影响使用，每次一调就在控制台出这么一堆，有没有大佬给看下什么原因: 2017-12-01 16:15:39.304 90f1586cd18c479cba5a3ad0d503c58c [http-nio-9513-exec-3] WARN com.alibaba.dubbo.validation.support.jvalidation.JValidator.warn:78 - [DUBBO] com.tceasy.tcmgr.provider.PmParkProvider$SelectByGmUserIdParameter: frozen class (cannot edit), dubbo version: 2.4.9, current host: 10.8.0.94 java.lang.RuntimeException: com.tceasy.tcmgr.provider.PmParkProvider$SelectByGmUserIdParameter: frozen class (cannot edit) at javassist.ClassPool.checkNotFrozen(ClassPool.java:617) at javassist.ClassPool.makeClass(ClassPool.java:859) at javassist.ClassPool.makeClass(ClassPool.java:836) at com.alibaba.dubbo.validation.support.jvalidation.JValidator.getMethodParameterBean(JValidator.java:166) at com.alibaba.dubbo.validation.support.jvalidation.JValidator.validate(JValidator.java:100) at com.alibaba.dubbo.validation.filter.ValidationFilter.invoke(ValidationFilter.java:49) at com.alibaba.dubbo.rpc.protocol.ProtocolFilterWrapper$1.invoke(ProtocolFilterWrapper.java:91) at com.alibaba.dubbo.rpc.protocol.dubbo.filter.FutureFilter.invoke(FutureFilter.java:53) at com.alibaba.dubbo.rpc.protocol.ProtocolFilterWrapper$1.invoke(ProtocolFilterWrapper.java:91) at com.alibaba.dubbo.monitor.support.MonitorFilter.invoke(MonitorFilter.java:75) at com.alibaba.dubbo.rpc.protocol.ProtocolFilterWrapper$1.invoke(ProtocolFilterWrapper.java:91) at com.alibaba.dubbo.rpc.filter.ConsumerContextFilter.invoke(ConsumerContextFilter.java:48) at com.alibaba.dubbo.rpc.protocol.ProtocolFilterWrapper$1.invoke(ProtocolFilterWrapper.java:91) at com.alibaba.dubbo.rpc.listener.ListenerInvokerWrapper.invoke(ListenerInvokerWrapper.java:74) at com.alibaba.dubbo.rpc.protocol.InvokerWrapper.invoke(InvokerWrapper.java:53) at com.alibaba.dubbo.rpc.cluster.support.FailoverClusterInvoker.doInvoke(FailoverClusterInvoker.java:77) at com.alibaba.dubbo.rpc.cluster.support.AbstractClusterInvoker.invoke(AbstractClusterInvoker.java:226) at com.alibaba.dubbo.rpc.cluster.support.wrapper.MockClusterInvoker.invoke(MockClusterInvoker.java:72) at com.alibaba.dubbo.rpc.proxy.InvokerInvocationHandler.invoke(InvokerInvocationHandler.java:52) at com.alibaba.dubbo.common.bytecode.proxy0.selectByGmUserId(proxy0.java) at com.tceasy.illegal.service.server.impl.BaseServiceImpl.getPmpark(BaseServiceImpl.java:491) at com.tceasy.illegal.service.server.impl.BaseServiceImpl.getParkName(BaseServiceImpl.java:292) at com.tceasy.illegal.service.server.impl.BaseServiceImpl.toSpecBean(BaseServiceImpl.java:279) at com.tceasy.illegal.service.server.impl.BaseServiceImpl.queryGmParkNotice(BaseServiceImpl.java:223) at com.tceasy.illegal.service.mgr.Impl.PeccancyServiceImpl.peccancyList(PeccancyServiceImpl.java:46) at com.tceasy.illegal.controller.mgr.MgrPeccancyController.peccancyList(MgrPeccancyController.java:56) at com.tceasy.illegal.controller.mgr.MgrPeccancyController$$FastClassBySpringCGLIB$$96d68e0c.invoke(<generated>) at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204) at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:738) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157) at org.springframework.aop.aspectj.MethodInvocationProceedingJoinPoint.proceed(MethodInvocationProceedingJoinPoint.java:85) at com.tceasy.aop.ResponseMessageAspect.exception(ResponseMessageAspect.java:30) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:606) at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethodWithGivenArgs(AbstractAspectJAdvice.java:629) at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethod(AbstractAspectJAdvice.java:618) at org.springframework.aop.aspectj.AspectJAroundAdvice.invoke(AspectJAroundAdvice.java:70) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:168) at org.springframework.aop.aspectj.MethodInvocationProceedingJoinPoint.proceed(MethodInvocationProceedingJoinPoint.java:85) at com.tceasy.aop.MyLogAspect.setMDC(MyLogAspect.java:54) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:606) at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethodWithGivenArgs(AbstractAspectJAdvice.java:629) at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethod(AbstractAspectJAdvice.java:618) at org.springframework.aop.aspectj.AspectJAroundAdvice.invoke(AspectJAroundAdvice.java:70) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:168) at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:673) at com.tceasy.illegal.controller.mgr.MgrPeccancyController$$EnhancerBySpringCGLIB$$be9f23e1.peccancyList(<generated>) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:606) at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:205) at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:133) at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:97) at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:827) at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:738) at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85) at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:963) at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:897) at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970) at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:872) at javax.servlet.http.HttpServlet.service(HttpServlet.java:661) at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846) at javax.servlet.http.HttpServlet.service(HttpServlet.java:742) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at com.alibaba.druid.support.http.WebStatFilter.doFilter(WebStatFilter.java:123) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at org.springframework.web.filter.HttpPutFormContentFilter.doFilterInternal(HttpPutFormContentFilter.java:105) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:81) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at org.springframework.session.web.http.SessionRepositoryFilter.doFilterInternal(SessionRepositoryFilter.java:167) at org.springframework.session.web.http.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:80) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:197) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)

为什么java后台无法获取到前台的部分值: <div role="tabpanel" class="tab-pane" id="signup-form"> <form action="/taixuewang/servlet/StudentSer" method="post"> <div class="form-group"> <div class="input-group"> <div class="input-group-addon"> <i class="fa fa-envelope" style="margin:0;"></i> </div> <input type="email" name="login" class="form-control" placeholder="请输入邮箱"> </div> </div> <div class="form-group"> <div class="input-group"> <div class="input-group-addon"> <i class="fa fa-lock" style="margin:0;"></i> </div> <input type="password" name="password" class="form-control" placeholder="请输入密码"> </div> </div> <div class="form-group"> <input class="btn btn-primary" type="submit" value="注册"> <input type="hidden" name="status" value="saveStudent"/> </div> <div class="form-group agree-privacy"> 注册表示您已经同意我们的<a href="privacy/index.html" target="_blank">隐私条款</a> </div> <div class="form-group widget-signup"> <span>快速注册</span> <a href="/auth/qq?next="><i class="fa fa-qq"></i></a> <a href="/auth/weibo?next="><i class="fa fa-weibo"></i></a> <a href="/auth/weixin?next="><i class="fa fa-weixin"></i></a> <a href="/auth/github?next="><i class="fa fa-github"></i></a> <a href="/auth/renren?next="><i class="fa fa-renren"></i></a> </div> </form> </div> ``` ``` null asdasd null 2017-11-21 17:35:54 org.apache.catalina.core.StandardWrapperValve invoke 严重: Servlet.service() for servlet StudentSer threw exception java.lang.NullPointerException at ser.StudentSer.doPost(StudentSer.java:88) at javax.servlet.http.HttpServlet.service(HttpServlet.java:710) at javax.servlet.http.HttpServlet.service(HttpServlet.java:803) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:230) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175) 我在控制台试着打印出email password 和status的value值可是只输出了password值想了一个下午实在想不出

困扰了一整天的bug，求帮助，: 我最近在用Maven做一个Javaweb项目，但是今天碰到了一个问题，我复制了报错信息百度搜索，上csdn,stackoverflow,等网站都没有找到解决的方法，我感觉是数据库的问题，但是我尝试过用JDBC来操作数据库，可以正常连接。数据库账号密码我确认过没有错误，我是跟着视频学的，刚刚接触java不久，希望能够得到大神的帮助，感激不尽全部报错信息如下： ``` java.lang.NullPointerException at java.util.Properties$LineReader.readLine(Properties.java:434) at java.util.Properties.load0(Properties.java:353) at java.util.Properties.load(Properties.java:341) at cn.itcast.travel.util.JDBCUtils.<clinit>(JDBCUtils.java:31) at cn.itcast.travel.dao.impl.UserDaoImpl.<init>(UserDaoImpl.java:10) at cn.itcast.travel.service.impl.UserServiceImpl.<init>(UserServiceImpl.java:9) at cn.itcast.travel.web.servlet.RegistUserServlet.doPost(RegistUserServlet.java:35) at javax.servlet.http.HttpServlet.service(HttpServlet.java:647) at javax.servlet.http.HttpServlet.service(HttpServlet.java:728) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99) at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:936) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407) at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1004) at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589) at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) at java.lang.Thread.run(Thread.java:748) 六月 21, 2019 10:40:52 下午 org.apache.catalina.core.StandardWrapperValve invoke 严重: Servlet.service() for servlet [cn.itcast.travel.web.servlet.RegistUserServlet] in context with path [/travel] threw exception java.lang.IllegalArgumentException: Property 'dataSource' is required at org.springframework.jdbc.support.JdbcAccessor.afterPropertiesSet(JdbcAccessor.java:135) at org.springframework.jdbc.core.JdbcTemplate.<init>(JdbcTemplate.java:169) at cn.itcast.travel.dao.impl.UserDaoImpl.<init>(UserDaoImpl.java:10) at cn.itcast.travel.service.impl.UserServiceImpl.<init>(UserServiceImpl.java:9) at cn.itcast.travel.web.servlet.RegistUserServlet.doPost(RegistUserServlet.java:35) at javax.servlet.http.HttpServlet.service(HttpServlet.java:647) at javax.servlet.http.HttpServlet.service(HttpServlet.java:728) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99) at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:936) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407) at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1004) at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589) at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) at java.lang.Thread.run(Thread.java:748) ``` 各位，我把项目上传到了百度云，里面的代码我都已经写好了，只要启动项目，在注册页面上填写注册信息，点击提交，控制台就会报错。数据库的代码就在项目的travel.sql文件中，感兴趣有时间的可以帮忙看一下我代码究竟那里出错了，不感兴趣的可以忽略这段话，如果不是实在没有头绪，我也不会做伸手党，这已经是第二天了，今天在解决不了，就要跳过项目学框架了。谢谢各位啦链接：https://pan.baidu.com/s/1KImj8iaxV9xy-cv5ri0LXg 提取码：fzwk 复制这段内容后打开百度网盘手机App，操作更方便哦

在中国程序员是青春饭吗？: 今年，我也32了，为了不给大家误导，咨询了猎头、圈内好友，以及年过35岁的几位老程序员……舍了老脸去揭人家伤疤……希望能给大家以帮助，记得帮我点赞哦。目录：你以为的人生一次又一次的伤害猎头界的真相如何应对互联网行业的「中年危机」一、你以为的人生刚入行时，拿着傲人的工资，想着好好干，以为我们的人生是这样的：等真到了那一天，你会发现，你的人生很可能是这样的： ...

《MySQL 性能优化》之理解 MySQL 体系结构: 本文介绍 MySQL 的体系结构，包括物理结构、逻辑结构以及插件式存储引擎。

程序员请照顾好自己，周末病魔差点一套带走我。: 程序员在一个周末的时间，得了重病，差点当场去世，还好及时挽救回来了。

Python+OpenCV实时图像处理: 目录 1、导入库文件 2、设计GUI 3、调用摄像头 4、实时图像处理 4.1、阈值二值化 4.2、边缘检测 4.3、轮廓检测 4.4、高斯滤波 4.5、色彩转换 4.6、调节对比度 5、退出系统初学OpenCV图像处理的小伙伴肯定对什么高斯函数、滤波处理、阈值二值化等特性非常头疼，这里给各位分享一个小项目，可通过摄像头实时动态查看各类图像处理的特点，也可对各位调参、测试...

2020年一线城市程序员工资大调查: 人才需求一线城市共发布岗位38115个，招聘120827人。其中 beijing 22805 guangzhou 25081 shanghai 39614 shenzhen 33327 工资分布 2020年中国一线城市程序员的平均工资为16285元，工资中位数为14583元，其中95%的人的工资位于5000到20000元之间。和往年数据比较： yea...

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害怕面试被问HashMap？这一篇就搞定了！: 声明：本文以jdk1.8为主！搞定HashMap 作为一个Java从业者，面试的时候肯定会被问到过HashMap，因为对于HashMap来说，可以说是Java集合中的精髓了，如果你觉得自己对它掌握的还不够好，我想今天这篇文章会非常适合你，至少，看了今天这篇文章，以后不怕面试被问HashMap了其实在我学习HashMap的过程中，我个人觉得HashMap还是挺复杂的，如果真的想把它搞得明明白...

毕业5年，我问遍了身边的大佬，总结了他们的学习方法: 我问了身边10个大佬，总结了他们的学习方法，原来成功都是有迹可循的。

python爬取百部电影数据，我分析出了一个残酷的真相: 2019年就这么匆匆过去了，就在前几天国家电影局发布了2019年中国电影市场数据，数据显示去年总票房为642.66亿元，同比增长5.4%；国产电影总票房411.75亿元，同比增长8.65%，市场占比 64.07%；城市院线观影人次17.27亿，同比增长0.64%。看上去似乎是一片大好对不对？不过作为一名严谨求实的数据分析师，我从官方数据中看出了一点端倪：国产票房增幅都已经高达8.65%了，为什...

推荐10个堪称神器的学习网站: 每天都会收到很多读者的私信，问我：“二哥，有什么推荐的学习网站吗？最近很浮躁，手头的一些网站都看烦了，想看看二哥这里有什么新鲜货。” 今天一早做了个恶梦，梦到被老板辞退了。虽然说在我们公司，只有我辞退老板的份，没有老板辞退我这一说，但是还是被吓得 4 点多都起来了。（主要是因为我掌握着公司所有的核心源码，哈哈哈）既然 4 点多起来，就得好好利用起来。于是我就挑选了 10 个堪称神器的学习网站，推...

这些软件太强了，Windows必装！尤其程序员！: Windows可谓是大多数人的生产力工具，集娱乐办公于一体，虽然在程序员这个群体中都说苹果是信仰，但是大部分不都是从Windows过来的，而且现在依然有很多的程序员用Windows。所以，今天我就把我私藏的Windows必装的软件分享给大家，如果有一个你没有用过甚至没有听过，那你就赚了????，这可都是提升你幸福感的高效率生产力工具哦！走起！???? NO、1 ScreenToGif 屏幕，摄像头和白板...

阿里面试，面试官没想到一个ArrayList，我都能跟他扯半小时: 我是真的没想到，面试官会这样问我ArrayList。

曾经优秀的人，怎么就突然不优秀了。: 职场上有很多辛酸事，很多合伙人出局的故事，很多技术骨干被裁员的故事。说来模板都类似，曾经是名校毕业，曾经是优秀员工，曾经被领导表扬，曾经业绩突出，然而突然有一天，因为种种原因，被裁员了，...

C语言荣获2019年度最佳编程语言: 关注、星标公众号，不错过精彩内容作者：黄工公众号：strongerHuang近日，TIOBE官方发布了2020年1月编程语言排行榜单。我在前面给过一篇文章《2019年11月C语言接近Ja...

大学四年因为知道了这32个网站，我成了别人眼中的大神！: 依稀记得，毕业那天，我们导员发给我毕业证的时候对我说“你可是咱们系的风云人物啊”，哎呀，别提当时多开心啦????，嗯，我们导员是所有导员中最帅的一个，真的???? 不过，导员说的是实话，很多人都叫我大神的，为啥，因为我知道这32个网站啊，你说强不强????，这次是绝对的干货，看好啦，走起来！ PS：每个网站都是学计算机混互联网必须知道的，真的牛杯，我就不过多介绍了，大家自行探索，觉得没用的，尽管留言吐槽吧???? 社...

良心推荐，我珍藏的一些Chrome插件: 上次搬家的时候，发了一个朋友圈，附带的照片中不小心暴露了自己的 Chrome 浏览器插件之多，于是就有小伙伴评论说分享一下我觉得还不错的浏览器插件。我下面就把我日常工作和学习中经常用到的一些 Chrome 浏览器插件分享给大家，随便一个都能提高你的“生活品质”和工作效率。 Markdown Here Markdown Here 可以让你更愉快的写邮件，由于支持 Markdown 直接转电子邮...

看完这篇HTTP，跟面试官扯皮就没问题了: 我是一名程序员，我的主要编程语言是 Java，我更是一名 Web 开发人员，所以我必须要了解 HTTP，所以本篇文章就来带你从 HTTP 入门到进阶，看完让你有一种恍然大悟、醍醐灌顶的感觉。最初在有网络之前，我们的电脑都是单机的，单机系统是孤立的，我还记得 05 年前那会儿家里有个电脑，想打电脑游戏还得两个人在一个电脑上玩儿，及其不方便。我就想为什么家里人不让上网，我的同学 xxx 家里有网，每...

史上最全的IDEA快捷键总结: 现在Idea成了主流开发工具，这篇博客对其使用的快捷键做了总结，希望对大家的开发工作有所帮助。

阿里程序员写了一个新手都写不出的低级bug，被骂惨了。: 这种新手都不会范的错，居然被一个工作好几年的小伙子写出来，差点被当场开除了。

谁是华为扫地僧？: 是的，华为也有扫地僧！2020年2月11-12日，“养在深闺人不知”的华为2012实验室扫地僧们，将在华为开发者大会2020（Cloud）上，和大家见面。到时，你可以和扫地僧们，吃一个洋...

AI 没让人类失业，搞 AI 的人先失业了: 最近和几个 AI 领域的大佬闲聊根据他们讲的消息和段子改编出下面这个故事如有雷同都是巧合 1. 老王创业失败，被限制高消费 “这里写我跑路的消息实在太夸张了。” 王葱葱哼笑一下，把消息分享给群里。阿杰也看了消息，笑了笑。在座几位也都笑了。王葱葱是个有名的人物，21岁那年以全额奖学金进入 KMU 攻读人工智能博士，累计发表论文 40 余篇，个人技术博客更是成为深度学习领域内风向标。 ...

2020年，冯唐49岁：我给20、30岁IT职场年轻人的建议: 点击“技术领导力”关注∆每天早上8:30推送作者|Mr.K 编辑| Emma 来源|技术领导力(ID：jishulingdaoli) 前天的推文《冯唐：职场人35岁以后，方法论比经验重要》，收到了不少读者的反馈，觉得挺受启发。其实，冯唐写了不少关于职场方面的文章，都挺不错的。可惜大家只记住了“春风十里不如你”、“如何避免成为油腻腻的中年人”等不那么正经的文章。本文整理了冯...

一份王者荣耀的英雄数据报告: 咪哥杂谈本篇阅读时间约为 6 分钟。1前言前一阵写了关于王者的一些系列文章，从数据的获取到数据清洗，数据落地，都是为了本篇的铺垫。今天来实现一下，看看不同维度得到的结论。2环境准备本次实...

作为一名大学生，如何在B站上快乐的学习？: B站是个宝，谁用谁知道???? 作为一名大学生，你必须掌握的一项能力就是自学能力，很多看起来很牛X的人，你可以了解下，人家私底下一定是花大量的时间自学的，你可能会说，我也想学习啊，可是嘞，该学习啥嘞，不怕告诉你，互联网时代，最不缺的就是学习资源，最宝贵的是啥？你可能会说是时间，不，不是时间，而是你的注意力，懂了吧！那么，你说学习资源多，我咋不知道，那今天我就告诉你一个你必须知道的学习的地方，人称...

那些年，我们信了课本里的那些鬼话: 教材永远都是有错误的，从小学到大学，我们不断的学习了很多错误知识。斑羚飞渡在我们学习的很多小学课文里，有很多是错误文章，或者说是假课文。像《斑羚飞渡》：随着镰刀头羊的那声吼叫，整个斑羚群迅速分成两拨，老年斑羚为一拨，年轻斑羚为一拨。就在这时，我看见，从那拨老斑羚里走出一只公斑羚来。公斑羚朝那拨年轻斑羚示意性地咩了一声，一只半大的斑羚应声走了出来。一老一少走到伤心崖，后退了几步，突...

一个程序在计算机中是如何运行的？超级干货！！！: 强烈声明：本文很干，请自备茶水！???? 开门见山，咱不说废话！你有没有想过，你写的程序，是如何在计算机中运行的吗？比如我们搞Java的，肯定写过这段代码 public class HelloWorld { public static void main(String[] args) { System.out.println("Hello World!"); } ...

【蘑菇街技术部年会】程序员与女神共舞，鼻血再次没止住。（文末内推）: 蘑菇街技术部的年会，别开生面，一样全是美女。

那个在阿里养猪的工程师，5年了……: 简介：在阿里，走过1825天，没有趴下，依旧斗志满满，被称为“五年陈”。他们会被授予一枚戒指，过程就叫做“授戒仪式”。今天，咱们听听阿里的那些“五年陈”们的故事。下一个五年，猪圈见！我就是那个在养猪场里敲代码的工程师，一年多前我和20位工程师去了四川的猪场，出发前总架构师慷慨激昂的说：同学们，中国的养猪产业将因为我们而改变。但到了猪场，发现根本不是那么回事：要个WIFI，没有；...

为什么程序猿都不愿意去外包？: 分享外包的组织架构，盈利模式，亲身经历，以及根据一些外包朋友的反馈，写了这篇文章，希望对正在找工作的老铁有所帮助

Java校招入职华为，半年后我跑路了: 何来我，一个双非本科弟弟，有幸在 19 届的秋招中得到前东家华为（以下简称 hw）的赏识，当时秋招签订就业协议，说是入了某 java bg，之后一系列组织架构调整原因等等让人无法理解的神操作，最终毕业前夕，被通知调往其他 bg 做嵌入式开发（纯 C 语言）。由于已至于校招末尾，之前拿到的其他 offer 又无法再收回，一时感到无力回天，只得默默接受。毕业后，直接入职开始了嵌入式苦旅，由于从未...

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