Exception in thread "Thread-12" java.lang.RuntimeException: java.lang.NullPointerException

第一次着手项目，springboot+mybatis，项目搭建是跟着教程做的。项目搭建好之后项目能正常运行，但是启动后报： Exception in thread "Thread-12" java.lang.RuntimeException: java.lang.NullPointerException at com.mysql.jdbc.JDBC4Connection$1$1.run(JDBC4Connection.java:106) Caused by: java.lang.NullPointerException at com.mysql.jdbc.ConnectionImpl.abortInternal(ConnectionImpl.java:1240) at com.mysql.jdbc.JDBC4Connection$1$1.run(JDBC4Connection.java:104) 启动Console： 2019-08-05 10:29:12.921 INFO 7416 --- [ restartedMain] com.xintujiuzhang.aimanagement.App : Starting App on DESKTOP-J57CTN6 with PID 7416 (D:\JAVA\eclipse\TaxHandwritingRecognition\target\classes started by Administrator in D:\JAVA\eclipse\TaxHandwritingRecognition) 2019-08-05 10:29:12.921 INFO 7416 --- [ restartedMain] com.xintujiuzhang.aimanagement.App : No active profile set, falling back to default profiles: default 2019-08-05 10:29:12.958 INFO 7416 --- [ restartedMain] ConfigServletWebServerApplicationContext : Refreshing org.springframework.boot.web.servlet.context.AnnotationConfigServletWebServerApplicationContext@6070b0bb: startup date [Mon Aug 05 10:29:12 CST 2019]; root of context hierarchy 2019-08-05 10:29:13.450 INFO 7416 --- [ restartedMain] o.s.b.f.xml.XmlBeanDefinitionReader : Loading XML bean definitions from class path resource [mybatis-config.xml] 2019-08-05 10:29:13.503 INFO 7416 --- [ restartedMain] o.s.b.f.s.DefaultListableBeanFactory : Overriding bean definition for bean 'sqlSessionFactory' with a different definition: replacing [Root bean: class [null]; scope=; abstract=false; lazyInit=false; autowireMode=3; dependencyCheck=0; autowireCandidate=true; primary=false; factoryBeanName=app; factoryMethodName=sqlSessionFactoryBean; initMethodName=null; destroyMethodName=(inferred); defined in com.xintujiuzhang.aimanagement.App] with [Generic bean: class [org.mybatis.spring.SqlSessionFactoryBean]; scope=; abstract=false; lazyInit=false; autowireMode=0; dependencyCheck=0; autowireCandidate=true; primary=false; factoryBeanName=null; factoryMethodName=null; initMethodName=null; destroyMethodName=null; defined in class path resource [mybatis-config.xml]] 2019-08-05 10:29:13.599 WARN 7416 --- [ restartedMain] o.m.s.mapper.ClassPathMapperScanner : No MyBatis mapper was found in '[com.xintujiuzhang.aimanagement]' package. Please check your configuration. 2019-08-05 10:29:13.958 INFO 7416 --- [ restartedMain] trationDelegate$BeanPostProcessorChecker : Bean 'org.springframework.transaction.annotation.ProxyTransactionManagementConfiguration' of type [org.springframework.transaction.annotation.ProxyTransactionManagementConfiguration$$EnhancerBySpringCGLIB$$b535b905] is not eligible for getting processed by all BeanPostProcessors (for example: not eligible for auto-proxying) 2019-08-05 10:29:14.332 INFO 7416 --- [ restartedMain] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat initialized with port(s): 8080 (http) 2019-08-05 10:29:14.348 INFO 7416 --- [ restartedMain] o.apache.catalina.core.StandardService : Starting service [Tomcat] 2019-08-05 10:29:14.349 INFO 7416 --- [ restartedMain] org.apache.catalina.core.StandardEngine : Starting Servlet Engine: Apache Tomcat/8.5.28 2019-08-05 10:29:14.355 INFO 7416 --- [ost-startStop-1] o.a.catalina.core.AprLifecycleListener : Loaded APR based Apache Tomcat Native library [1.2.21] using APR version [1.6.5]. 2019-08-05 10:29:14.355 INFO 7416 --- [ost-startStop-1] o.a.catalina.core.AprLifecycleListener : APR capabilities: IPv6 [true], sendfile [true], accept filters [false], random [true]. 2019-08-05 10:29:14.355 INFO 7416 --- [ost-startStop-1] o.a.catalina.core.AprLifecycleListener : APR/OpenSSL configuration: useAprConnector [false], useOpenSSL [true] 2019-08-05 10:29:14.357 INFO 7416 --- [ost-startStop-1] o.a.catalina.core.AprLifecycleListener : OpenSSL successfully initialized [OpenSSL 1.1.1a 20 Nov 2018] 2019-08-05 10:29:14.418 INFO 7416 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext 2019-08-05 10:29:14.418 INFO 7416 --- [ost-startStop-1] o.s.web.context.ContextLoader : Root WebApplicationContext: initialization completed in 1462 ms 2019-08-05 10:29:14.514 INFO 7416 --- [ost-startStop-1] o.s.b.w.servlet.ServletRegistrationBean : Servlet dispatcherServlet mapped to [/] 2019-08-05 10:29:14.517 INFO 7416 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'characterEncodingFilter' to: [/*] 2019-08-05 10:29:14.517 INFO 7416 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'hiddenHttpMethodFilter' to: [/*] 2019-08-05 10:29:14.517 INFO 7416 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'httpPutFormContentFilter' to: [/*] 2019-08-05 10:29:14.517 INFO 7416 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'requestContextFilter' to: [/*] 2019-08-05 10:29:14.631 INFO 7416 --- [ restartedMain] com.zaxxer.hikari.HikariDataSource : HikariPool-1 - Starting... 2019-08-05 10:29:19.625 INFO 7416 --- [ restartedMain] com.zaxxer.hikari.pool.PoolBase : HikariPool-1 - Driver does not support get/set network timeout for connections. (com.mysql.jdbc.JDBC4Connection.getNetworkTimeout()I) 2019-08-05 10:29:19.629 INFO 7416 --- [ restartedMain] com.zaxxer.hikari.HikariDataSource : HikariPool-1 - Start completed. 2019-08-05 10:29:19.670 INFO 7416 --- [ restartedMain] j.LocalContainerEntityManagerFactoryBean : Building JPA container EntityManagerFactory for persistence unit 'default' 2019-08-05 10:29:19.684 INFO 7416 --- [ restartedMain] o.hibernate.jpa.internal.util.LogHelper : HHH000204: Processing PersistenceUnitInfo [ name: default ...] 2019-08-05 10:29:19.738 INFO 7416 --- [ restartedMain] org.hibernate.Version : HHH000412: Hibernate Core {5.2.10.Final} 2019-08-05 10:29:19.739 INFO 7416 --- [ restartedMain] org.hibernate.cfg.Environment : HHH000206: hibernate.properties not found 2019-08-05 10:29:19.770 INFO 7416 --- [ restartedMain] o.hibernate.annotations.common.Version : HCANN000001: Hibernate Commons Annotations {5.0.1.Final} 2019-08-05 10:29:19.874 INFO 7416 --- [ restartedMain] org.hibernate.dialect.Dialect : HHH000400: Using dialect: org.hibernate.dialect.MySQL5Dialect 2019-08-05 10:29:19.897 INFO 7416 --- [ restartedMain] o.h.e.j.e.i.LobCreatorBuilderImpl : HHH000423: Disabling contextual LOB creation as JDBC driver reported JDBC version [3] less than 4 2019-08-05 10:29:20.037 INFO 7416 --- [ restartedMain] j.LocalContainerEntityManagerFactoryBean : Initialized JPA EntityManagerFactory for persistence unit 'default' 10:29:20,543 INFO App:32-org.springframework.orm.jpa.JpaTransactionManager 2019-08-05 10:29:20.796 INFO 7416 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerAdapter : Looking for @ControllerAdvice: org.springframework.boot.web.servlet.context.AnnotationConfigServletWebServerApplicationContext@6070b0bb: startup date [Mon Aug 05 10:29:12 CST 2019]; root of context hierarchy 2019-08-05 10:29:20.824 WARN 7416 --- [ restartedMain] aWebConfiguration$JpaWebMvcConfiguration : spring.jpa.open-in-view is enabled by default. Therefore, database queries may be performed during view rendering. Explicitly configure spring.jpa.open-in-view to disable this warning 2019-08-05 10:29:20.846 INFO 7416 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/application/handwriting_authorization],methods=[GET]}" onto public java.lang.String com.xintujiuzhang.aimanagement.controller.ApplicationAuthorizationController.joinHWA(java.util.Map<java.lang.String, java.lang.Object>) 2019-08-05 10:29:20.847 INFO 7416 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/application/handwriting_information],methods=[GET]}" onto public java.lang.String com.xintujiuzhang.aimanagement.controller.ApplicationInformationController.joinHWI(java.util.Map<java.lang.String, java.lang.Object>) 2019-08-05 10:29:20.847 INFO 7416 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/log/background_management_login],methods=[GET]}" onto public java.lang.String com.xintujiuzhang.aimanagement.controller.BackgroundManagementLoginController.joinHWI(java.util.Map<java.lang.String, java.lang.Object>) 2019-08-05 10:29:20.847 INFO 7416 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/log/computer_login],methods=[GET]}" onto public java.lang.String com.xintujiuzhang.aimanagement.controller.ComputerLoginController.jumpDEM(java.util.Map<java.lang.String, java.lang.Object>) 2019-08-05 10:29:20.847 INFO 7416 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/authority/department_management],methods=[GET]}" onto public java.lang.String com.xintujiuzhang.aimanagement.controller.DepartmentManagementController.jumpDEM(java.util.Map<java.lang.String, java.lang.Object>) 2019-08-05 10:29:20.848 INFO 7416 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/authority/dictionary_management],methods=[GET]}" onto public java.lang.String com.xintujiuzhang.aimanagement.controller.DictionaryManagementController.jumpDM(java.util.Map<java.lang.String, java.lang.Object>) 2019-08-05 10:29:20.848 INFO 7416 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/equipment/hardware_devices],methods=[GET]}" onto public java.lang.String com.xintujiuzhang.aimanagement.controller.EquipmentManagementController.jumpDM(java.util.Map<java.lang.String, java.lang.Object>) 2019-08-05 10:29:20.848 INFO 7416 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/queryGetServerStatusInterface],methods=[GET]}" onto public java.util.Map<java.lang.String, java.lang.Object> com.xintujiuzhang.aimanagement.controller.GetServerStatusInterfaceController.queryGetServerStatus(java.lang.String,java.lang.String) 2019-08-05 10:29:20.848 INFO 7416 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/queryHandwritingInterface],methods=[GET]}" onto public java.util.Map<java.lang.String, java.lang.Object> com.xintujiuzhang.aimanagement.controller.HandwritingInterfaceController.queryHandwriting(java.lang.String,java.lang.String,java.lang.Integer,java.util.Date) 2019-08-05 10:29:20.849 INFO 7416 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/identity/identity_management],methods=[GET]}" onto public java.lang.String com.xintujiuzhang.aimanagement.controller.IdentityManagementController.jumpDM(java.util.Map<java.lang.String, java.lang.Object>) 2019-08-05 10:29:20.849 INFO 7416 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/queryInstallationRequest],methods=[GET]}" onto public java.util.Map<java.lang.String, java.lang.Object> com.xintujiuzhang.aimanagement.controller.InstallationRequestInterfaceController.queryInstallationRequest(java.lang.String,java.lang.String,java.lang.String) 2019-08-05 10:29:20.849 INFO 7416 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/queryLicenseInterface],methods=[GET]}" onto public java.util.Map<java.lang.String, java.lang.Object> com.xintujiuzhang.aimanagement.controller.LicenseInterfaceController.queryLicense(java.lang.String,java.lang.String,java.lang.String,java.lang.String,java.lang.String,java.util.Date) 2019-08-05 10:29:20.851 INFO 7416 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/]}" onto public java.lang.String com.xintujiuzhang.aimanagement.controller.MainController.main(java.util.Map<java.lang.String, java.lang.Object>) 2019-08-05 10:29:20.851 INFO 7416 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/login],methods=[GET]}" onto public org.springframework.web.servlet.ModelAndView com.xintujiuzhang.aimanagement.controller.MainController.login() 2019-08-05 10:29:20.851 INFO 7416 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/login],methods=[POST]}" onto public java.lang.String com.xintujiuzhang.aimanagement.controller.MainController.login(java.lang.String,java.lang.String,java.util.Map<java.lang.String, java.lang.Object>) 2019-08-05 10:29:20.851 INFO 7416 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/main],methods=[GET]}" onto public java.lang.String com.xintujiuzhang.aimanagement.controller.MainController.jumpmain(java.util.Map<java.lang.String, java.lang.Object>) 2019-08-05 10:29:20.852 INFO 7416 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/authority/menu_management],methods=[GET]}" onto public java.lang.String com.xintujiuzhang.aimanagement.controller.MenuManagementController.jumpMM(java.util.Map<java.lang.String, java.lang.Object>) 2019-08-05 10:29:20.852 INFO 7416 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/log/module_browsing],methods=[GET]}" onto public java.lang.String com.xintujiuzhang.aimanagement.controller.ModuleBrowsingController.jumpTM(java.util.Map<java.lang.String, java.lang.Object>) 2019-08-05 10:29:20.852 INFO 7416 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/log/module_operation],methods=[GET]}" onto public java.lang.String com.xintujiuzhang.aimanagement.controller.ModuleOperationController.jumpMM(java.util.Map<java.lang.String, java.lang.Object>) 2019-08-05 10:29:20.852 INFO 7416 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/deletehandwriting],methods=[POST]}" onto public void com.xintujiuzhang.aimanagement.controller.NotesController.deletehandwriting(java.lang.String) 2019-08-05 10:29:20.852 INFO 7416 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/updatehandwriting],methods=[POST]}" onto public void com.xintujiuzhang.aimanagement.controller.NotesController.updatehandwriting(com.xintujiuzhang.aimanagement.pojo.Handwriting) 2019-08-05 10:29:20.852 INFO 7416 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/addhandwriting],methods=[POST]}" onto public void com.xintujiuzhang.aimanagement.controller.NotesController.addhandwriting(com.xintujiuzhang.aimanagement.pojo.Handwriting) 2019-08-05 10:29:20.853 INFO 7416 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/querynotes],methods=[GET]}" onto public com.xintujiuzhang.aimanagement.pojo.Handwriting com.xintujiuzhang.aimanagement.controller.NotesController.querynotes(java.lang.String) 2019-08-05 10:29:20.853 INFO 7416 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/authority/parameter_settings],methods=[GET]}" onto public java.lang.String com.xintujiuzhang.aimanagement.controller.parameterSettingsController.jumpPS(java.util.Map<java.lang.String, java.lang.Object>) 2019-08-05 10:29:20.853 INFO 7416 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/authority/role_authorization],methods=[GET]}" onto public java.lang.String com.xintujiuzhang.aimanagement.controller.RoleAuthorizationController.jumpRA(java.util.Map<java.lang.String, java.lang.Object>) 2019-08-05 10:29:20.853 INFO 7416 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/log/service_call],methods=[GET]}" onto public java.lang.String com.xintujiuzhang.aimanagement.controller.ServiceCallController.jumpRA(java.util.Map<java.lang.String, java.lang.Object>) 2019-08-05 10:29:20.853 INFO 7416 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/authority/task_management],methods=[GET]}" onto public java.lang.String com.xintujiuzhang.aimanagement.controller.TaskManagementController.jumpTM(java.util.Map<java.lang.String, java.lang.Object>) 2019-08-05 10:29:20.854 INFO 7416 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/authority/user_management]}" onto public java.lang.String com.xintujiuzhang.aimanagement.controller.UserController.jnmpUM(java.util.Map<java.lang.String, java.lang.Object>) 2019-08-05 10:29:20.854 INFO 7416 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/queryUserInterface],methods=[GET]}" onto public java.util.Map<java.lang.String, java.lang.Object> com.xintujiuzhang.aimanagement.controller.UserInterfaceController.queryLicense(java.lang.String,java.lang.String,java.lang.Integer,java.util.Date) 2019-08-05 10:29:20.854 INFO 7416 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/queryVersionCheckingInterface],methods=[GET]}" onto public java.util.Map<java.lang.String, java.lang.Object> com.xintujiuzhang.aimanagement.controller.VersionCheckingInterfaceController.queryVersionChecking(java.lang.String,java.lang.String,java.lang.String,java.lang.String,java.lang.String,java.lang.Integer,java.util.Date) 2019-08-05 10:29:20.854 INFO 7416 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/queryVersionupdateInterface],methods=[GET]}" onto public java.util.Map<java.lang.String, java.lang.Object> com.xintujiuzhang.aimanagement.controller.VersionUpdateInterfaceController.queryVersionupdate(java.lang.String,java.lang.String,java.lang.String,java.util.Date) 2019-08-05 10:29:20.857 INFO 7416 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error]}" onto public org.springframework.http.ResponseEntity<java.util.Map<java.lang.String, java.lang.Object>> org.springframework.boot.autoconfigure.web.servlet.error.BasicErrorController.error(javax.servlet.http.HttpServletRequest) 2019-08-05 10:29:20.857 INFO 7416 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error],produces=[text/html]}" onto public org.springframework.web.servlet.ModelAndView org.springframework.boot.autoconfigure.web.servlet.error.BasicErrorController.errorHtml(javax.servlet.http.HttpServletRequest,javax.servlet.http.HttpServletResponse) 2019-08-05 10:29:20.881 INFO 7416 --- [ restartedMain] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/webjars/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler] 2019-08-05 10:29:20.881 INFO 7416 --- [ restartedMain] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler] 2019-08-05 10:29:20.906 INFO 7416 --- [ restartedMain] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**/favicon.ico] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler] 2019-08-05 10:29:21.115 INFO 7416 --- [ restartedMain] o.s.b.d.a.OptionalLiveReloadServer : LiveReload server is running on port 35729 2019-08-05 10:29:21.164 INFO 7416 --- [ restartedMain] o.s.j.e.a.AnnotationMBeanExporter : Registering beans for JMX exposure on startup 2019-08-05 10:29:21.165 INFO 7416 --- [ restartedMain] o.s.j.e.a.AnnotationMBeanExporter : Bean with name 'dataSource' has been autodetected for JMX exposure 2019-08-05 10:29:21.170 INFO 7416 --- [ restartedMain] o.s.j.e.a.AnnotationMBeanExporter : Located MBean 'dataSource': registering with JMX server as MBean [com.zaxxer.hikari:name=dataSource,type=HikariDataSource] 2019-08-05 10:29:21.196 INFO 7416 --- [ restartedMain] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat started on port(s): 8080 (http) with context path '' 2019-08-05 10:29:21.198 INFO 7416 --- [ restartedMain] com.xintujiuzhang.aimanagement.App : Started App in 8.458 seconds (JVM running for 8.828) Exception in thread "Thread-12" java.lang.RuntimeException: java.lang.NullPointerException at com.mysql.jdbc.JDBC4Connection$1$1.run(JDBC4Connection.java:106) Caused by: java.lang.NullPointerException at com.mysql.jdbc.ConnectionImpl.abortInternal(ConnectionImpl.java:1240) at com.mysql.jdbc.JDBC4Connection$1$1.run(JDBC4Connection.java:104) **在执行一些方法后“Thread-12”会不断增加** **ps：“Thread-668"**

java.lang.NullPointerException

java.lang.NullPointerException java.lang.String.<init>(String.java:228) com.huawei.support.mobile.module.web.jsintf.WebIntf.AesDecrypt(Unknown Source) com.huawei.support.mobile.module.web.jsintf.WebIntf.login(Unknown Source) com.huawei.support.mobile.module.web.ui.HWSupportMobileWebContainer.sendNetState(Unknown Source) com.huawei.support.mobile.module.web.ui.j.onPageFinished(Unknown Source) com.android.webview.chromium.WebViewContentsClientAdapter.onPageFinished(WebViewContentsClientAdapter.java:488) com.android.org.chromium.android_webview.AwContentsClient$AwWebContentsObserver$1.run(AwContentsClient.java:76) android.os.Handler.handleCallback(Handler.java:733) android.os.Handler.dispatchMessage(Handler.java:95) android.os.Looper.loop(Looper.java:136) android.app.ActivityThread.main(ActivityThread.java:5314) java.lang.reflect.Method.invokeNative(Native Method) java.lang.reflect.Method.invoke(Method.java:515) com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:864) com.android.internal.os.ZygoteInit.main(ZygoteInit.java:680) dalvik.system.NativeStart.main(Native Method) 求大神解答这个错误是怎么出来的 ,现在就出现了一次

SSM 遇到的java.lang.NullPointerException问题

报错 java.lang.NullPointerException ** at com.archives.controller.sysmanage.DepartmentController.doPageData(DepartmentController.java:38) ** at com.archives.controller.sy****smanage.DepartmentController.initHome(DepartmentController.java:32) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:220) at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:134) at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:116) 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.doGet(FrameworkServlet.java:861) at javax.servlet.http.HttpServlet.service(HttpServlet.java:624) at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846) 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:197) 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:169) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103) at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:956) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:436) at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1078) at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:625) at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.doRun(AprEndpoint.java:2517) at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.run(AprEndpoint.java:2506) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) at java.lang.Thread.run(Thread.java:748) mapper.xml 文件 <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" > <mapper namespace="com.archives.dao.UserDeptDao"> <resultMap id="userdeptMap" type="com.archives.entity.UserDept"> <id column="deptid" property="deptid"></id> <result column="deptname" property="deptname"/> <result column="telephone" property="telephone"/> <result column="fax" property="fax"/> <result column="managerid" property="managerid"/> <result column="remark" property="remark"/> <association property="userInfo" javaType="com.archives.entity.UserInfo"> <id column="loginid" property="loginid"></id> <result column="loginname" property="loginname"/> <result column="loginpwd" property="loginpwd"/> <result column="realname" property="realname"/> <result column="roleid" property="roleid"/> <result column="leveid" property="leveid"/> <result column="cardid" property="cardid"/> <result column="dutyid" property="dutyid"/> <result column="deptid" property="deptid"/> <result column="joindate" property="joindate"/> <result column="telephone" property="telephone"/> <result column="enduid" property="enduid"/> <result column="address" property="address"/> <result column="sex" property="sex"/> </association> </resultMap> <select id="selectUserDeptCount" parameterType="com.archives.model.A0104Model" resultType="Integer"> select count(*) as cnt from userinfo,dept and userinfo.deptid = dept.deptid <if test="loginname != null and loginname.trim() != '' "> and userinfo.loginname = #{loginname} </if> <if test="realname != null and realname.trim() != '' "> and userinfo.realname = #{realname} </if> <if test="deptname != null and deptname.trim() != '' "> and dept.deptname = #{deptname} </if> </select> <select id="selectUserDeptList" parameterType="com.archives.model.A0104Model" resultMap="userdeptMap"> select userinfo.loginid , userinfo.loginname , userinfo.realname , dept.deptname , dept.deptid from userinfo,dept where userinfo.deptid = dept.deptid limit #{offsetindex},#{pageCount} </select> </mapper> controller.java文件 package com.archives.controller.sysmanage; import java.util.List; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpSession; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Controller; import org.springframework.web.bind.annotation.RequestMapping; import com.alibaba.fastjson.JSON; import com.archives.common.Constant; import com.archives.entity.Menu; import com.archives.entity.UserDept; import com.archives.entity.UserInfo; import com.archives.model.A0104Model; import com.archives.service.HomeService; import com.archives.service.UserDeptService; @Controller @RequestMapping("/department") public class DepartmentController { UserDeptService userdeptService; @RequestMapping("/init") public String initHome(HttpServletRequest request) { A0104Model model=new A0104Model(); model.setCurPage(1); model.setPageCount(Constant.PAGE_COUNT); 对应的错误行**doPageData(request,model);** return "department"; } private void doPageData(HttpServletRequest request, A0104Model model) { // TODO Auto-generated method stub int cnt = userdeptService.selectUserDeptCount(model); int totalPage = 0; if(cnt%Constant.PAGE_COUNT == 0) { totalPage = cnt/Constant.PAGE_COUNT; }else { totalPage = cnt/Constant.PAGE_COUNT + 1; } model.setTotalPage(totalPage); model.setOffsetindex((model.getCurPage() - 1) * Constant.PAGE_COUNT); model.setPageCount(Constant.PAGE_COUNT); 对应的错误行**List<UserDept> userdeptduiyList=userdeptService.selectUserDeptList(model);** request.setAttribute("userdeptList", userdeptList); request.setAttribute("model", model); } } model.java文件 package com.archives.model; public class A0104Model { private String loginname; private String realname; private String deptname; public String getLoginname() { return loginname; } public void setLoginname(String loginname) { this.loginname = loginname; } public String getRealname() { return realname; } public void setRealname(String realname) { this.realname = realname; } public String getDeptname() { return deptname; } public void setDeptname(String deptname) { this.deptname = deptname; } public int getCurPage() { return curPage; } public void setCurPage(int curPage) { this.curPage = curPage; } public int getTotalPage() { return totalPage; } public void setTotalPage(int totalPage) { this.totalPage = totalPage; } public int getOffsetindex() { return offsetindex; } public void setOffsetindex(int offsetindex) { this.offsetindex = offsetindex; } public int getPageCount() { return pageCount; } public void setPageCount(int pageCount) { this.pageCount = pageCount; } private int curPage; private int totalPage; private int offsetindex; private int pageCount; } Dao package com.archives.dao; import java.util.List; import com.archives.entity.UserDept; import com.archives.model.A0104Model; public interface UserDeptDao { UserDeptDao getUserDeptByName(String loginname); int selectUserDeptCount(A0104Model model); List<UserDept> selectUserDeptList(A0104Model model); } service package com.archives.service; import java.util.List; import com.archives.entity.UserDept; import com.archives.model.A0104Model; public interface UserDeptService { int selectUserDeptCount(A0104Model model); List<UserDept> selectUserDeptList(A0104Model model); } serviceImpl package com.archives.service; import java.util.List; import com.archives.dao.UserDeptDao; import com.archives.entity.UserDept; import com.archives.model.A0104Model; public class UserDeptServiceImpl implements UserDeptService { UserDeptDao userdeptDao; @Override public int selectUserDeptCount(A0104Model model) { // TODO Auto-generated method stub int cnt=userdeptDao.selectUserDeptCount(model); return cnt; } @Override public List<UserDept> selectUserDeptList(A0104Model model) { // TODO Auto-generated method stub List<UserDept> userdeptList =userdeptDao.selectUserDeptList(model); return userdeptList; } } UserDept.java package com.archives.entity; public class UserDept { private int deptid; private String deptname; private String telephone; private String fax; private String managerid; private String remark; public String getTelephone() { return telephone; } public void setTelephone(String telephone) { this.telephone = telephone; } public String getFax() { return fax; } public void setFax(String fax) { this.fax = fax; } public String getManagerid() { return managerid; } public void setManagerid(String managerid) { this.managerid = managerid; } public String getRemark() { return remark; } public void setRemark(String remark) { this.remark = remark; } public int getDeptid() { return deptid; } public void setDeptid(int deptid) { this.deptid = deptid; } public String getDeptname() { return deptname; } public void setDeptname(String deptname) { this.deptname = deptname; } public String getLoginid() { return loginid; } public void setLoginid(String loginid) { this.loginid = loginid; } public String getLoginname() { return loginname; } public void setLoginname(String loginname) { this.loginname = loginname; } public String getRealname() { return realname; } public void setRealname(String realname) { this.realname = realname; } private String loginid; private String loginname; private String realname; }

struts1.2 运行提示java.lang.NullPointerException错误

java.lang.NullPointerException org.apache.struts.config.FormBeanConfig.createActionForm(FormBeanConfig.java:289)

java 中出现 java.lang.nullpointerexception异常

java 中出现 java.lang.nullpointerexception异常，哪位大神能帮忙处理一下 http://pan.baidu.com/share/link?shareid=3804041701&uk=840289731

java.lang.String[] java.lang.String.split

Error, Qchat service has not been published java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String[] java.lang.String.split(java.lang.String)' on a null object reference 这个问题怎么解决，求神助。。。

安卓：java.lang.NullPointerException:

logcat显示错误： FATAL EXCEPTION: main Process: org.droidplanner, PID: 21924 java.lang.RuntimeException: Unable to resume activity {org.droidplanner/org.droidplanner.android.activities.FlightActivity}: java.lang.NullPointerException: Attempt to read from field 'android.content.SharedPreferences org.droidplanner.android.utils.prefs.DroidPlannerPrefs.prefs' on a null object reference at android.app.ActivityThread.performResumeActivity(ActivityThread.java:3019) at android.app.ActivityThread.handleResumeActivity(ActivityThread.java:3050) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2425) at android.app.ActivityThread.access$900(ActivityThread.java:154) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1321) at android.os.Handler.dispatchMessage(Handler.java:102) at android.os.Looper.loop(Looper.java:135) at android.app.ActivityThread.main(ActivityThread.java:5294) at java.lang.reflect.Method.invoke(Native Method) at java.lang.reflect.Method.invoke(Method.java:372) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:904) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:699)

Servlet遇到java.lang.NullPointerException问题无法解决，恳求帮助

各位大佬，最近用Jsp+servlet写教务管理系统，其中servlet端有一个问题始终无法解决 ``` 严重: Servlet.service() for servlet [com.jwglxt.data.searchStudent] in context with path [/jwglxt] threw exception java.lang.NullPointerException ``` 目的是根据从前台传来的查询类型和查询关键词在数据库中进行检索，目前前后端数据传递正常，NullPointerException这个问题始终得不到解决，尝试了很多办法都不行，恳请各位大佬施以援手！ 代码如下： ```java package com.jwglxt.data; import java.io.IOException; import java.io.PrintWriter; import java.sql.Connection; import java.sql.DriverManager; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.ResultSetMetaData; import java.sql.SQLException; import java.sql.Statement; 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 org.json.JSONArray; import org.json.JSONException; import org.json.JSONObject; //思路：绑定一个弹出框在“搜索”按钮上，弹出框里放置一个datagrid,url为searchStudent @WebServlet("/searchStudent") public class searchStudent extends HttpServlet { @SuppressWarnings({ "null", "null", "null" }) protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { //设置编码格式 request.setCharacterEncoding("UTF-8"); response.setCharacterEncoding("utf-8"); response.setContentType("text/json; charset=utf-8"); //获取学生信息主码-学号（sno） String name=request.getParameter("name"); System.out.println("搜索类型:"+name); String value=request.getParameter("value"); System.out.println("搜索值:"+value); //姑且赋值 /*String name="sno"; String value="990101";*/ //连接数据库 Connection connection=null; String driverName="com.microsoft.sqlserver.jdbc.SQLServerDriver";//SQL数据库引擎 String dbURL="jdbc:sqlserver://localhost:1433;DatabaseName=tjl";//数据源 ！！！注意若出现加载或者连接数据库失败一般是这里出现问题 String Name="sa"; String Pwd="19990713"; ResultSet rs=null; String sql="sql"; //定义JSON数组，用于保存从数据库查出来的数据 JSONArray array = new JSONArray(); try { Class.forName(driverName); connection=DriverManager.getConnection(dbURL,Name,Pwd); System.out.println("搜索学生:连接数据库成功"); } catch (ClassNotFoundException e2) { e2.printStackTrace(); }catch (SQLException e) { e.printStackTrace(); } //处理搜索类型 尝试switch语句 /*switch(name) { case "sno":{ try { sql="select * from student where sno=?"; connection.prepareStatement(sql); pstmt.setString(1,value); //rs=pstmt.executeQuery(sql); } catch (SQLException e) { e.printStackTrace(); };break; }//case }//switch */ //处理搜索类型 尝试If语句 if(name!=null) { if("sno".equals(name)){ try { //仅构造SQL语句，暂不运行 sql="select * from student where sno=?"; PreparedStatement pstmt=connection.prepareStatement(sql); pstmt.setString(1,value); rs = pstmt.executeQuery(sql); } catch (SQLException e) { e.printStackTrace(); } } else if("sname".equals(name)){ try { //仅构造SQL语句，暂不运行 sql="select * from student where sname=?"; PreparedStatement pstmt=connection.prepareStatement(sql); pstmt.setString(1,value); rs = pstmt.executeQuery(sql); } catch (SQLException e) { e.printStackTrace(); } } else if("sex".equals(name)){ try { //仅构造SQL语句，暂不运行 sql="select * from student where sex=?"; PreparedStatement pstmt=connection.prepareStatement(sql); pstmt.setString(1,value); rs = pstmt.executeQuery(sql); } catch (SQLException e) { e.printStackTrace(); } } else if("dno".equals(name)){ try { //仅构造SQL语句，暂不运行 sql="select * from student where dno=?"; PreparedStatement pstmt=connection.prepareStatement(sql); pstmt.setString(1,value); rs = pstmt.executeQuery(sql); } catch (SQLException e) { e.printStackTrace(); } } else { try { //仅构造SQL语句，暂不运行 sql="select * from student where dormno=?"; PreparedStatement pstmt=connection.prepareStatement(sql); pstmt.setString(1,value); rs = pstmt.executeQuery(sql); } catch (SQLException e) { e.printStackTrace(); } } System.out.println(sql); } try { // 获取列数 ResultSetMetaData metaData = rs.getMetaData(); int columnCount = metaData.getColumnCount(); while (rs.next()) { JSONObject jsonObj = new JSONObject(); // 遍历每一列 for (int i = 1; i <= columnCount; i++) { String columnName =metaData.getColumnLabel(i); String value2 = rs.getString(columnName); try { jsonObj.put(columnName, value2); } catch (JSONException e) { // TODO Auto-generated catch block e.printStackTrace(); } } array.put(jsonObj); } } catch (SQLException e1) { e1.printStackTrace(); } //关闭 try { if(rs!=null) rs.close(); //pstmt.close(); connection.close(); } catch (SQLException e) { e.printStackTrace(); } //PrintWriter out = response.getWriter(); System.out.println(array); }//总类 protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); } public static void main(String args[]) { searchStudent ss=new searchStudent(); try { ss.doGet(null, null); } catch (ServletException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } } } ```

win8 安装oracle11g时报出java.lang.nullpointerexception

win8 安装oracle11g时报出java.lang.nullpointerexception，无法进入安装界面，求解决！ 谢谢

多线程 java.lang.NullPointerException

``` Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException at javax.swing.plaf.basic.BasicListUI.paintImpl(BasicListUI.java:266) at javax.swing.plaf.basic.BasicListUI.paint(BasicListUI.java:240) at javax.swing.plaf.ComponentUI.update(ComponentUI.java:161) at javax.swing.JComponent.paintComponent(JComponent.java:780) at javax.swing.JComponent.paint(JComponent.java:1056) at javax.swing.JComponent.paintToOffscreen(JComponent.java:5219) at javax.swing.RepaintManager$PaintManager.paintDoubleBuffered(RepaintManager.java:1572) at javax.swing.RepaintManager$PaintManager.paint(RepaintManager.java:1495) at javax.swing.RepaintManager.paint(RepaintManager.java:1265) at javax.swing.JComponent._paintImmediately(JComponent.java:5167) at javax.swing.JComponent.paintImmediately(JComponent.java:4978) at javax.swing.RepaintManager$4.run(RepaintManager.java:824) at javax.swing.RepaintManager$4.run(RepaintManager.java:807) at java.security.AccessController.doPrivileged(Native Method) at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:75) at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:807) at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:782) at javax.swing.RepaintManager.prePaintDirtyRegions(RepaintManager.java:731) at javax.swing.RepaintManager.access$1300(RepaintManager.java:64) at javax.swing.RepaintManager$ProcessingRunnable.run(RepaintManager.java:1720) at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:311) at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:756) at java.awt.EventQueue.access$500(EventQueue.java:97) at java.awt.EventQueue$3.run(EventQueue.java:709) at java.awt.EventQueue$3.run(EventQueue.java:703) at java.security.AccessController.doPrivileged(Native Method) at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:75) at java.awt.EventQueue.dispatchEvent(EventQueue.java:726) at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:201) at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116) at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93) at java.awt.EventDispatchThread.run(EventDispatchThread.java:82) ``` ## 我写了个socket通信的小程序，，每次启动一个客户端就创建一个线程专门用来读取Server回复的信息，主线程用来往Server发信息。 ## 有时 ，当我启动到第多个客户端时就会报出该异常，但是程序还是正常运行的。。只是在该客户端控制台输出了这些异常信息，有时一个一个关闭客户端时也会报该异常， 而这些不是我的代码里的东西，，求指导。这是异常是关于什么的。？？

学习用MyEclipse 2013开发SSH项目遇到java.lang.NullPointerException问题，请帮助！

**SaveOfficeAction.java出错：java.lang.NullPointerException** package we.app.action; import we.app.data.*; import com.opensymphony.xwork2.ActionSupport; public class SaveOfficeAction extends ActionSupport { private IOffice B_Office; private IOfficeDAO B_OfficeDAO; private String Tips; public IOffice getB_Office() { return B_Office; } public void setB_Office(IOffice b_Office) { B_Office = b_Office; } public IOfficeDAO getB_OfficeDAO() { return B_OfficeDAO; } public void setB_OfficeDAO(IOfficeDAO b_OfficeDAO) { B_OfficeDAO = b_OfficeDAO; } public String getTips() { return Tips; } public void setTips(String tips) { Tips = tips; } public String execute() throws Exception { this.Tips=this.getB_OfficeDAO().findById(1).getOfficename().toString(); //this.Trans_OfficeDAO.save(this.B_Office); return SUCCESS; } } **1、index.jsp：** <%@taglib uri="/struts-tags" prefix="s"%><%@ page language="java" import="java.util.*" pageEncoding="ISO-8859-1"%> <% String path = request.getContextPath(); String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"; %> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <base href="<%=basePath%>"> <title>My JSP 'index.jsp' starting page</title> <meta http-equiv="pragma" content="no-cache"> <meta http-equiv="cache-control" content="no-cache"> <meta http-equiv="expires" content="0"> <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"> <meta http-equiv="description" content="This is my page"> <!-- <link rel="stylesheet" type="text/css" href="styles.css"> --> </head> <body> <s:form action="SaveOffice"> <s:textfield name="B_Office.officename" label="officename"></s:textfield> <s:submit></s:submit> </s:form> <br> </body> </html> **2、hibernate.cfg.xml:** <?xml version='1.0' encoding='UTF-8'?> <!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd"> <!-- Generated by MyEclipse Hibernate Tools. --> <hibernate-configuration> <session-factory> <property name="dialect">org.hibernate.dialect.SQLServerDialect</property> <property name="connection.url"> jdbc:jtds:sqlserver://192.168.0.100:4628/tnew </property> <property name="connection.username">sa</property> <property name="connection.password">111</property> <property name="connection.driver_class"> net.sourceforge.jtds.jdbc.Driver </property> <property name="myeclipse.connection.profile"> sqlserverjtds </property> <mapping resource="we/app/data/Peop.hbm.xml" /> <mapping resource="we/app/data/Office.hbm.xml" /> </session-factory> </hibernate-configuration> 3、ApplicationContext.xml <?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:p="http://www.springframework.org/schema/p" xmlns:tx="http://www.springframework.org/schema/tx" xmlns:aop="http://www.springframework.org/schema/aop" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.1.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.1.xsd" > <bean id="sessionFactory" class="org.springframework.orm.hibernate3.LocalSessionFactoryBean"> <property name="configLocation" value="classpath:hibernate.cfg.xml"> </property> </bean> <bean id="PeopDAO" class="we.app.data.PeopDAO"> <property name="sessionFactory" ref="sessionFactory"></property> </bean> <bean id="B_OfficeDAO" class="we.app.data.OfficeDAO"> <property name="sessionFactory" ref="sessionFactory"></property> </bean> <bean id="B_Office" class="we.app.data.Office"></bean> <bean id="B_Peop" class="we.app.data.Peop"></bean> <bean id="transactionManager" class="org.springframework.orm.hibernate3.HibernateTransactionManager"> <property name="sessionFactory"> <ref bean="sessionFactory"/> </property> </bean> <bean id="Trans_OfficeDAO" class="org.springframework.transaction.interceptor.TransactionProxyFactoryBean"> <property name="transactionManager"> <ref bean="transactionManager" /> </property> <property name="target"> <ref local="B_OfficeDAO" /> </property> <property name="transactionAttributes"> <props> <prop key="*">PROPAGATION_REQUIRED</prop> </props> </property> </bean> </beans> 4、 package we.app.data; import java.util.List; public interface IOfficeDAO { // property constants public static final String OFFICENAME = "officename"; public abstract void save(IOffice transientInstance); public abstract void delete(IOffice persistentInstance); public abstract IOffice findById(java.lang.Integer id); public abstract List findByExample(IOffice instance); public abstract List findByProperty(String propertyName, Object value); public abstract List findByOfficename(Object officename); public abstract List findAll(); public abstract IOffice merge(Office detachedInstance); public abstract void attachDirty(IOffice instance); public abstract void attachClean(IOffice instance); }

Error querying database. Cause: java.lang.NullPointerException

###错误日志 org.mybatis.spring.MyBatisSystemException: nested exception is org.apache.ibatis.exceptions.PersistenceException: Error querying database. Cause: java.lang.NullPointerException Cause: java.lang.NullPointerException at org.mybatis.spring.MyBatisExceptionTranslator.translateExceptionIfPossible(MyBatisExceptionTranslator.java:79) at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:447) at com.sun.proxy.$Proxy82.selectOne(Unknown Source) at org.mybatis.spring.SqlSessionTemplate.selectOne(SqlSessionTemplate.java:167) at org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:75) at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:53) at com.sun.proxy.$Proxy180.shareRewardList(Unknown Source) at com.cn.ym.live.hottalk.service.common.impl.UserInfoServiceImpl.shareRewardList(UserInfoServiceImpl.java:82) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Unknown Source) at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:333) at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:190) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157) at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:213) at com.sun.proxy.$Proxy178.shareRewardList(Unknown Source) at com.cn.ym.live.hottalk.controller.UserInfoController.shareRewardList(UserInfoController.java:119) at com.cn.ym.live.hottalk.controller.UserInfoController$$FastClassBySpringCGLIB$$728252b4.invoke(<generated>) at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204) at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:738) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157) at org.springframework.validation.beanvalidation.MethodValidationInterceptor.invoke(MethodValidationInterceptor.java:139) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) at org.springframework.aop.aspectj.MethodInvocationProceedingJoinPoint.proceed(MethodInvocationProceedingJoinPoint.java:85) at com.cn.ym.live.hottalk.aop.WebControllerAop.doAround(WebControllerAop.java:46) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Unknown Source) at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethodWithGivenArgs(AbstractAspectJAdvice.java:629) at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethod(AbstractAspectJAdvice.java:618) at org.springframework.aop.aspectj.AspectJAroundAdvice.invoke(AspectJAroundAdvice.java:70) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:673) at com.cn.ym.live.hottalk.controller.UserInfoController$$EnhancerBySpringCGLIB$$e47575b0.shareRewardList(<generated>) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Unknown Source) 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 io.undertow.servlet.handlers.ServletHandler.handleRequest(ServletHandler.java:85) at io.undertow.servlet.handlers.FilterHandler$FilterChainImpl.doFilter(FilterHandler.java:129) at com.cn.ym.live.hottalk.aop.MyFilter.doFilter(MyFilter.java:62) at io.undertow.servlet.core.ManagedFilter.doFilter(ManagedFilter.java:61) at io.undertow.servlet.handlers.FilterHandler$FilterChainImpl.doFilter(FilterHandler.java:131) at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) at io.undertow.servlet.core.ManagedFilter.doFilter(ManagedFilter.java:61) at io.undertow.servlet.handlers.FilterHandler$FilterChainImpl.doFilter(FilterHandler.java:131) at org.springframework.web.filter.HttpPutFormContentFilter.doFilterInternal(HttpPutFormContentFilter.java:105) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) at io.undertow.servlet.core.ManagedFilter.doFilter(ManagedFilter.java:61) at io.undertow.servlet.handlers.FilterHandler$FilterChainImpl.doFilter(FilterHandler.java:131) at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:81) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) at io.undertow.servlet.core.ManagedFilter.doFilter(ManagedFilter.java:61) at io.undertow.servlet.handlers.FilterHandler$FilterChainImpl.doFilter(FilterHandler.java:131) at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:197) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) at io.undertow.servlet.core.ManagedFilter.doFilter(ManagedFilter.java:61) at io.undertow.servlet.handlers.FilterHandler$FilterChainImpl.doFilter(FilterHandler.java:131) at io.undertow.servlet.handlers.FilterHandler.handleRequest(FilterHandler.java:84) at io.undertow.servlet.handlers.security.ServletSecurityRoleHandler.handleRequest(ServletSecurityRoleHandler.java:62) at io.undertow.servlet.handlers.ServletDispatchingHandler.handleRequest(ServletDispatchingHandler.java:36) at io.undertow.servlet.handlers.security.SSLInformationAssociationHandler.handleRequest(SSLInformationAssociationHandler.java:131) at io.undertow.servlet.handlers.security.ServletAuthenticationCallHandler.handleRequest(ServletAuthenticationCallHandler.java:57) at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) at io.undertow.security.handlers.AbstractConfidentialityHandler.handleRequest(AbstractConfidentialityHandler.java:46) at io.undertow.servlet.handlers.security.ServletConfidentialityConstraintHandler.handleRequest(ServletConfidentialityConstraintHandler.java:64) at io.undertow.security.handlers.AuthenticationMechanismsHandler.handleRequest(AuthenticationMechanismsHandler.java:60) at io.undertow.servlet.handlers.security.CachedAuthenticatedSessionHandler.handleRequest(CachedAuthenticatedSessionHandler.java:77) at io.undertow.security.handlers.AbstractSecurityContextAssociationHandler.handleRequest(AbstractSecurityContextAssociationHandler.java:43) at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) at io.undertow.servlet.handlers.SessionRestoringHandler.handleRequest(SessionRestoringHandler.java:119) at io.undertow.servlet.handlers.ServletInitialHandler.handleFirstRequest(ServletInitialHandler.java:292) at io.undertow.servlet.handlers.ServletInitialHandler.access$100(ServletInitialHandler.java:81) at io.undertow.servlet.handlers.ServletInitialHandler$2.call(ServletInitialHandler.java:138) at io.undertow.servlet.handlers.ServletInitialHandler$2.call(ServletInitialHandler.java:135) at io.undertow.servlet.core.ServletRequestContextThreadSetupAction$1.call(ServletRequestContextThreadSetupAction.java:48) at io.undertow.servlet.core.ContextClassLoaderSetupAction$1.call(ContextClassLoaderSetupAction.java:43) at io.undertow.servlet.handlers.ServletInitialHandler.dispatchRequest(ServletInitialHandler.java:272) at io.undertow.servlet.handlers.ServletInitialHandler.access$000(ServletInitialHandler.java:81) at io.undertow.servlet.handlers.ServletInitialHandler$1.handleRequest(ServletInitialHandler.java:104) at io.undertow.server.Connectors.executeRootHandler(Connectors.java:211) at io.undertow.server.HttpServerExchange$1.run(HttpServerExchange.java:809) at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) at java.lang.Thread.run(Unknown Source) Caused by: org.apache.ibatis.exceptions.PersistenceException: ### Error querying database. Cause: java.lang.NullPointerException ### Cause: java.lang.NullPointerException at org.apache.ibatis.exceptions.ExceptionFactory.wrapException(ExceptionFactory.java:30) at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:150) at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:141) at org.apache.ibatis.session.defaults.DefaultSqlSession.selectOne(DefaultSqlSession.java:77) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Unknown Source) at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:434) ... 104 common frames omitted Caused by: java.lang.NullPointerException: null at com.cn.ym.live.hottalk.config.db.MyAbstractRoutingDataSource.determineCurrentLookupKey(MyAbstractRoutingDataSource.java:24) at org.springframework.jdbc.datasource.lookup.AbstractRoutingDataSource.determineTargetDataSource(AbstractRoutingDataSource.java:196) at org.springframework.jdbc.datasource.lookup.AbstractRoutingDataSource.getConnection(AbstractRoutingDataSource.java:164) at com.github.pagehelper.PageHelper.getUrl(PageHelper.java:281) at com.github.pagehelper.PageHelper.getSqlUtil(PageHelper.java:305) at com.github.pagehelper.PageHelper.initSqlUtil(PageHelper.java:263) at com.github.pagehelper.PageHelper.intercept(PageHelper.java:250) at org.apache.ibatis.plugin.Plugin.invoke(Plugin.java:61) at com.sun.proxy.$Proxy168.query(Unknown Source) at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:148) ... 111 common frames omitted 2018-12-20 17:20:15.347 WARN 9616 --- [ XNIO-3 task-1] .m.m.a.ExceptionHandlerExceptionResolver : Resolved exception caused by Handler execution: org.mybatis.spring.MyBatisSystemException: nested exception is org.apache.ibatis.exceptions.PersistenceException: Error querying database. Cause: java.lang.NullPointerException Cause: java.lang.NullPointerException ###mapper.xml <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE mapper PUBLIC "-//ibatis.apache.org//DTD Mapper 3.0//EN" "http://ibatis.apache.org/dtd/ibatis-3-mapper.dtd"> <mapper namespace="com.cn.ym.live.hottalk.dao.UserInviteLogDAO"> <!-- --> <select id="shareRewardList" resultType="ShareReward"> SELECT COUNT(invite_id) as number, SUM(coin) as money FROM hot_user_invite_log </select> ###dao层 public interface UserInviteLogDAO { /** * 日志增加用户邀请奖励 奖励金额 * * @param inviteLog */ public void addCoin(InviteLog inviteLog); /** * 获取邀请码 用户信息 * * @param map uid * @return */ public UserInfo userInviteLogDao(Map<String, Object> map1); /** * 用户获取邀请信息 * * @param uid * @param start_time * @param end_time * @return */ public ShareReward shareRewardList(); ###service @Autowired private UserInviteLogDAO userInviteLogDao; @Autowired private PayOrderDAO payOrderDAO; private static final Logger logger = LoggerFactory.getLogger(UserInfoService.class); /** * 用户获取邀请信息 * @param uid * @param start_time * @param end_time * @return */ public ShareReward shareRewardList(String uid, Long start_time, Long end_time) { Map<String , Object> map =new HashMap<>(); map.put("uid", uid); map.put("start_time", start_time); map.put("end_time", end_time); ShareReward shareReward = userInviteLogDao.shareRewardList(); return shareReward; }

java web java.lang.NullPointerException

严重: Servlet.service() for servlet [selectServlet] in context with path [/Exercise] threw exception java.lang.NullPointerException at DB.DataBaseConnection.selectOperation1(DataBaseConnection.java:45) at Servlet.Select.doPost(Select.java:69) at javax.servlet.http.HttpServlet.service(HttpServlet.java:646) at javax.servlet.http.HttpServlet.service(HttpServlet.java:727) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303) 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:504) 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:421) at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1074) at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:611) at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:316) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:885) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:907) at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) at java.lang.Thread.run(Thread.java:619) 代码： public class DataBaseConnection { static String driverString="com.mysql.jdbc.Driver"; static String urlString="jdbc:mysql://localhost:3306/book"; static String username="root"; static String password="123"; public static Connection getConnection() { Connection connection; try { Class.forName(driverString); } catch (ClassNotFoundException e) { e.printStackTrace(); return null; // TODO: handle exception } try { connection=DriverManager.getConnection(urlString, username, password); } catch (SQLException e) { e.printStackTrace(); return null; // TODO: handle exception } return connection; } public static ResultSet selectOperation1(String Content,String SelectWay) { Connection connection=getConnection(); Statement statement=null; try { statement=connection.createStatement();//这一行报错。。 String sqlString="select * from bookinfo where 1=1"; if(Content!=""&&SelectWay!="") { sqlString+="and"+SelectWay+"='"+Content+"'"; } ResultSet rs=statement.executeQuery(sqlString); return rs; } catch (SQLException e) { e.printStackTrace(); return null; // TODO: handle exception } }

新人求助 java.lang.NullPointerException

04-26 21:42:40.039: E/AndroidRuntime(1125): FATAL EXCEPTION: main 04-26 21:42:40.039: E/AndroidRuntime(1125): Process: com.example.remotecontrol, PID: 1125 04-26 21:42:40.039: E/AndroidRuntime(1125): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.remotecontrol/com.example.remotecontrol.RemoteControlActivity}: java.lang.NullPointerException 04-26 21:42:40.039: E/AndroidRuntime(1125): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2176) 04-26 21:42:40.039: E/AndroidRuntime(1125): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2226) 04-26 21:42:40.039: E/AndroidRuntime(1125): at android.app.ActivityThread.access$700(ActivityThread.java:135) 04-26 21:42:40.039: E/AndroidRuntime(1125): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1397) 04-26 21:42:40.039: E/AndroidRuntime(1125): at android.os.Handler.dispatchMessage(Handler.java:102) 04-26 21:42:40.039: E/AndroidRuntime(1125): at android.os.Looper.loop(Looper.java:137) 04-26 21:42:40.039: E/AndroidRuntime(1125): at android.app.ActivityThread.main(ActivityThread.java:4998) 04-26 21:42:40.039: E/AndroidRuntime(1125): at java.lang.reflect.Method.invokeNative(Native Method) 04-26 21:42:40.039: E/AndroidRuntime(1125): at java.lang.reflect.Method.invoke(Method.java:515) 04-26 21:42:40.039: E/AndroidRuntime(1125): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:777) 04-26 21:42:40.039: E/AndroidRuntime(1125): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:593) 04-26 21:42:40.039: E/AndroidRuntime(1125): at dalvik.system.NativeStart.main(Native Method) 04-26 21:42:40.039: E/AndroidRuntime(1125): Caused by: java.lang.NullPointerException 04-26 21:42:40.039: E/AndroidRuntime(1125): at com.example.remotecontrol.RemoteControlFragment.onCreateView(RemoteControlFragment.java:43) 04-26 21:42:40.039: E/AndroidRuntime(1125): at android.support.v4.app.Fragment.performCreateView(Fragment.java:1500) 04-26 21:42:40.039: E/AndroidRuntime(1125): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:927) 04-26 21:42:40.039: E/AndroidRuntime(1125): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1104) 04-26 21:42:40.039: E/AndroidRuntime(1125): at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:682) 04-26 21:42:40.039: E/AndroidRuntime(1125): at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1467) 04-26 21:42:40.039: E/AndroidRuntime(1125): at android.support.v4.app.FragmentActivity.onStart(FragmentActivity.java:570) 04-26 21:42:40.039: E/AndroidRuntime(1125): at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1171) 04-26 21:42:40.039: E/AndroidRuntime(1125): at android.app.Activity.performStart(Activity.java:5253) 04-26 21:42:40.039: E/AndroidRuntime(1125): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2149) 04-26 21:42:40.039: E/AndroidRuntime(1125): ... 11 more

java.lang.NullPointerException希望各位大佬帮帮忙，找了半天真的不晓得咋弄了

 HTTP Status 500 – Internal Server Error Type Exception Report Message java.lang.NullPointerException Description The server encountered an unexpected condition that prevented it from fulfilling the request. Exception org.apache.jasper.JasperException: java.lang.NullPointerException org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:565) org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:481) org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:385) org.apache.jasper.servlet.JspServlet.service(JspServlet.java:329) javax.servlet.http.HttpServlet.service(HttpServlet.java:742) org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) Root Cause java.lang.NullPointerException service.userservice.valiUser(userservice.java:18) org.apache.jsp.validate_jsp._jspService(validate_jsp.java:139) org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70) javax.servlet.http.HttpServlet.service(HttpServlet.java:742) org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:443) org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:385) org.apache.jasper.servlet.JspServlet.service(JspServlet.java:329) javax.servlet.http.HttpServlet.service(HttpServlet.java:742) org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) Note The full stack trace of the root cause is available in the server logs. Apache Tomcat/8.5.20

java.lang.ClassNotFoundException

java.lang.ClassNotFoundException: com.example.zhenyi.common.SocketRequest at java.net.URLClassLoader$1.run(Unknown Source) at java.net.URLClassLoader$1.run(Unknown Source) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(Unknown Source) at java.lang.ClassLoader.loadClass(Unknown Source) at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source) at java.lang.ClassLoader.loadClass(Unknown Source) at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Unknown Source) at java.io.ObjectInputStream.resolveClass(Unknown Source) at java.io.ObjectInputStream.readNonProxyDesc(Unknown Source) at java.io.ObjectInputStream.readClassDesc(Unknown Source) at java.io.ObjectInputStream.readOrdinaryObject(Unknown Source) at java.io.ObjectInputStream.readObject0(Unknown Source) at java.io.ObjectInputStream.readObject(Unknown Source) at net.android.hospital.util.SocketUtil.getRequest(SocketUtil.java:16) at net.android.hospital.MainServer$ThreadHandler.run(MainServer.java:52) at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) at java.lang.Thread.run(Unknown Source) Exception in thread "pool-1-thread-1" java.lang.NullPointerException at net.android.hospital.MainServer$ThreadHandler.run(MainServer.java:62) at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) at java.lang.Thread.run(Unknown Source)

java List做函数参数 出现空指针错误java.lang.NullPointerException，错误的语句如下：

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