spring boot 整合mybatis 取别名时遇到问题

![图片说明](https://img-ask.csdn.net/upload/201705/23/1495530657_491711.png)图片说明为什么这样查到的数据都是null???
http://blog.csdn.net/jrainbow/article/details/51980036 照着这个弄的一个框架 以前用搭建好的框架也是这样取个别名 get set 就可以得到的呀

2个回答

具体没有提供BlackList和其映射的mapper的xml文件。
看打印情况,黑名单数据是查到了,查到了2条,但是部分信息没有映射到BlackList里来,比如starttime和stoptime,userid。
检查下你的mapper文件的字段映射关系,字段名称是否和数据库字段名称的映射关系ok

chenmingmingyo
陈名名 回复乔丹码得: 是的 @Result(property = "starttime", column = "start_time"), 需要这样写才行
2 年多之前 回复
penghaiping1001
乔丹码得 回复陈名名: 明白了,你用的mybatis,去除了xml映射,但是你starttime和stoptime,userid这些字段名字要和数据库的名字一致
接近 3 年之前 回复
chenmingmingyo
陈名名 回复乔丹码得: 整个项目只有一个没用的web。xml 还有就是maven依赖的一个xml 跟一个配置端口那些的yml
接近 3 年之前 回复
penghaiping1001
乔丹码得 回复陈名名: 不是,是BlackList对应的那个操作数据库的mapper映射的xml文件,直白点就是放sql语句的那个文件
接近 3 年之前 回复
chenmingmingyo
陈名名 只看都有一个配置ip端口什么的xml
接近 3 年之前 回复
chenmingmingyo
陈名名 理解不是很深。。是下面这个嘛?
接近 3 年之前 回复

package xyz.cmm.smartblocker.common.configure;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import tk.mybatis.spring.mapper.MapperScannerConfigurer;

import java.util.Properties;

/**

  • MyBatis扫描接口,使用的tk.mybatis.spring.mapper.MapperScannerConfigurer,
  • 如果你不使用通用Mapper, 可以改为org.xxx... *
  • @author liuzh
  • @since 2015-12-19 14:46
    */
    @Configuration
    public class MyBatisMapperScannerConfig {

    @Bean
    public MapperScannerConfigurer mapperScannerConfigurer() {
    MapperScannerConfigurer mapperScannerConfigurer = new MapperScannerConfigurer();
    mapperScannerConfigurer
    .setSqlSessionFactoryBeanName("sqlSessionFactory");
    mapperScannerConfigurer.setBasePackage("xyz.cmm.smartblocker.*.dao");
    Properties properties = new Properties();
    properties
    .setProperty("mappers", "xyz.cmm.smartblocker.common.BaseDao");
    properties.setProperty("notEmpty", "false");
    properties.setProperty("IDENTITY", "MYSQL");
    mapperScannerConfigurer.setProperties(properties);

    return mapperScannerConfigurer;
    

    }

}


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# 在持久层测试运行的时候出现以下错误,一直找不出什么原因 ``` org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'dataSource' defined in class path resource [org/springframework/boot/autoconfigure/jdbc/DataSourceConfiguration$Hikari.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.zaxxer.hikari.HikariDataSource]: Factory method 'dataSource' threw exception; nested exception is java.lang.IllegalStateException: Cannot load driver class: com.mysql.jdbc.Driver at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:587) ~[spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1250) ~[spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE] at 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~[spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE] at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199) ~[spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE] at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:760) ~[spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE] at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:869) ~[spring-context-5.0.5.RELEASE.jar:5.0.5.RELEASE] at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:550) ~[spring-context-5.0.5.RELEASE.jar:5.0.5.RELEASE] at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:759) ~[spring-boot-2.0.1.RELEASE.jar:2.0.1.RELEASE] at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:395) ~[spring-boot-2.0.1.RELEASE.jar:2.0.1.RELEASE] at 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[spring-test-5.0.5.RELEASE.jar:5.0.5.RELEASE] at org.springframework.test.context.web.ServletTestExecutionListener.prepareTestInstance(ServletTestExecutionListener.java:132) [spring-test-5.0.5.RELEASE.jar:5.0.5.RELEASE] at org.springframework.test.context.TestContextManager.prepareTestInstance(TestContextManager.java:246) [spring-test-5.0.5.RELEASE.jar:5.0.5.RELEASE] at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.createTest(SpringJUnit4ClassRunner.java:227) [spring-test-5.0.5.RELEASE.jar:5.0.5.RELEASE] at org.springframework.test.context.junit4.SpringJUnit4ClassRunner$1.runReflectiveCall(SpringJUnit4ClassRunner.java:289) [spring-test-5.0.5.RELEASE.jar:5.0.5.RELEASE] at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12) [junit-4.12.jar:4.12] at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.methodBlock(SpringJUnit4ClassRunner.java:291) [spring-test-5.0.5.RELEASE.jar:5.0.5.RELEASE] at 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[.cp/:na] Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.zaxxer.hikari.HikariDataSource]: Factory method 'dataSource' threw exception; nested exception is java.lang.IllegalStateException: Cannot load driver class: com.mysql.jdbc.Driver at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:185) ~[spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE] at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:579) ~[spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE] ... 42 common frames omitted Caused by: java.lang.IllegalStateException: Cannot load driver class: com.mysql.jdbc.Driver at org.springframework.util.Assert.state(Assert.java:94) ~[spring-core-5.0.5.RELEASE.jar:5.0.5.RELEASE] at org.springframework.boot.autoconfigure.jdbc.DataSourceProperties.determineDriverClassName(DataSourceProperties.java:224) ~[spring-boot-autoconfigure-2.0.1.RELEASE.jar:2.0.1.RELEASE] at org.springframework.boot.autoconfigure.jdbc.DataSourceProperties.initializeDataSourceBuilder(DataSourceProperties.java:176) ~[spring-boot-autoconfigure-2.0.1.RELEASE.jar:2.0.1.RELEASE] at org.springframework.boot.autoconfigure.jdbc.DataSourceConfiguration.createDataSource(DataSourceConfiguration.java:43) ~[spring-boot-autoconfigure-2.0.1.RELEASE.jar:2.0.1.RELEASE] at org.springframework.boot.autoconfigure.jdbc.DataSourceConfiguration$Hikari.dataSource(DataSourceConfiguration.java:81) ~[spring-boot-autoconfigure-2.0.1.RELEASE.jar:2.0.1.RELEASE] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_171] at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[na:1.8.0_171] at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[na:1.8.0_171] at java.lang.reflect.Method.invoke(Unknown Source) ~[na:1.8.0_171] at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:154) ~[spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE] ... 43 common frames omitted ```
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刚接触Spring Boot 不久,今天用 Spring Boot + Mybatis 按照网上的方法配置多数据源, 配置了多个DataConfig,并给其中一个打上了Primary注解,现在出现这样的问题: 给哪个数据源加Primary注解哪个数据源才能查询成功,其他的数据源一查就报异常,搞了好久不知道哪出的问题,各位大婶帮忙看看,下面是堆栈信息 org.mybatis.spring.MyBatisSystemException: nested exception is org.apache.ibatis.builder.BuilderException: Error invoking SqlProvider method (tk.mybatis.mapper.provider.ExampleProvider.dynamicSQL). Cause: java.lang.InstantiationException: tk.mybatis.mapper.provider.ExampleProvider at org.mybatis.spring.MyBatisExceptionTranslator.translateExceptionIfPossible(MyBatisExceptionTranslator.java:79) at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:447) at com.sun.proxy.$Proxy62.selectList(Unknown Source) at org.mybatis.spring.SqlSessionTemplate.selectList(SqlSessionTemplate.java:231) at org.apache.ibatis.binding.MapperMethod.executeForMany(MapperMethod.java:128) at org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:68) at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:53) at com.sun.proxy.$Proxy67.selectByExample(Unknown Source) at com.hworld.clp.component.companysetting.CompanySettingComponentImpl.getVerifyCodeSettings(CompanySettingComponentImpl.java:38) at com.hworld.clp.service.member.MemberServiceImpl.verifyCodeSetting(MemberServiceImpl.java:368) at com.hworld.clp.service.member.MemberServiceImpl.sendVerifyCode(MemberServiceImpl.java:280) at com.hworld.clp.controller.member.MemberController.sendVerifyCode(MemberController.java:78) 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: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:967) at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:901) 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 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:108) 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.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) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:199) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:504) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342) at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:803) at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:790) at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1459) at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) at java.lang.Thread.run(Thread.java:748) Caused by: org.apache.ibatis.builder.BuilderException: Error invoking SqlProvider method (tk.mybatis.mapper.provider.ExampleProvider.dynamicSQL). Cause: java.lang.InstantiationException: tk.mybatis.mapper.provider.ExampleProvider at org.apache.ibatis.builder.annotation.ProviderSqlSource.createSqlSource(ProviderSqlSource.java:102) at org.apache.ibatis.builder.annotation.ProviderSqlSource.getBoundSql(ProviderSqlSource.java:73) at org.apache.ibatis.mapping.MappedStatement.getBoundSql(MappedStatement.java:292) at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:81) at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:148) at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:141) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:434) ... 64 more Caused by: java.lang.InstantiationException: tk.mybatis.mapper.provider.ExampleProvider at java.lang.Class.newInstance(Class.java:427) at org.apache.ibatis.builder.annotation.ProviderSqlSource.createSqlSource(ProviderSqlSource.java:85) ... 74 more Caused by: java.lang.NoSuchMethodException: tk.mybatis.mapper.provider.ExampleProvider.<init>() at java.lang.Class.getConstructor0(Class.java:3082) at java.lang.Class.newInstance(Class.java:412) ... 75 more
Spring Boot + Mybatis 配置多数据源出错
刚接触Spring Boot 不久,今天用 Spring Boot + Mybatis 按照网上的方法配置多数据源, 配置了多个DataConfig,并给其中一个打上了Primary注解,现在出现这样的问题: 给哪个数据源加Primary注解哪个数据源才能查询成功,其他的数据源一查就报异常,搞了好久不知道哪出的问题,各位大婶帮忙看看,下面是堆栈信息 org.mybatis.spring.MyBatisSystemException: nested exception is org.apache.ibatis.builder.BuilderException: Error invoking SqlProvider method (tk.mybatis.mapper.provider.ExampleProvider.dynamicSQL). Cause: java.lang.InstantiationException: tk.mybatis.mapper.provider.ExampleProvider at org.mybatis.spring.MyBatisExceptionTranslator.translateExceptionIfPossible(MyBatisExceptionTranslator.java:79) at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:447) at com.sun.proxy.$Proxy62.selectList(Unknown Source) at org.mybatis.spring.SqlSessionTemplate.selectList(SqlSessionTemplate.java:231) at org.apache.ibatis.binding.MapperMethod.executeForMany(MapperMethod.java:128) at org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:68) at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:53) at com.sun.proxy.$Proxy67.selectByExample(Unknown Source) at com.hworld.clp.component.companysetting.CompanySettingComponentImpl.getVerifyCodeSettings(CompanySettingComponentImpl.java:38) at com.hworld.clp.service.member.MemberServiceImpl.verifyCodeSetting(MemberServiceImpl.java:368) at com.hworld.clp.service.member.MemberServiceImpl.sendVerifyCode(MemberServiceImpl.java:280) at com.hworld.clp.controller.member.MemberController.sendVerifyCode(MemberController.java:78) 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: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:967) at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:901) 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 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:108) 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.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) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:199) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:504) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342) at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:803) at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:790) at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1459) at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) at java.lang.Thread.run(Thread.java:748) Caused by: org.apache.ibatis.builder.BuilderException: Error invoking SqlProvider method (tk.mybatis.mapper.provider.ExampleProvider.dynamicSQL). Cause: java.lang.InstantiationException: tk.mybatis.mapper.provider.ExampleProvider at org.apache.ibatis.builder.annotation.ProviderSqlSource.createSqlSource(ProviderSqlSource.java:102) at org.apache.ibatis.builder.annotation.ProviderSqlSource.getBoundSql(ProviderSqlSource.java:73) at org.apache.ibatis.mapping.MappedStatement.getBoundSql(MappedStatement.java:292) at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:81) at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:148) at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:141) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:434) ... 64 more Caused by: java.lang.InstantiationException: tk.mybatis.mapper.provider.ExampleProvider at java.lang.Class.newInstance(Class.java:427) at org.apache.ibatis.builder.annotation.ProviderSqlSource.createSqlSource(ProviderSqlSource.java:85) ... 74 more Caused by: java.lang.NoSuchMethodException: tk.mybatis.mapper.provider.ExampleProvider.() at java.lang.Class.getConstructor0(Class.java:3082) at java.lang.Class.newInstance(Class.java:412) ... 75 more
spring-boot mybatis 查询mysql报错问题
``` 2018-06-24 17:32:23.171 ERROR 6371 --- [nio-8080-exec-1] o.a.c.c.C.[.[.[/].[dispatcherServlet] : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is org.mybatis.spring.MyBatisSystemException: nested exception is org.apache.ibatis.exceptions.PersistenceException: ### Error querying database. Cause: java.lang.NullPointerException ### The error may exist in file [/Users/ww/IdeaProjects/test-Service/test-Search/target/classes/mapping/TestMapper.xml] ### The error may involve com.test.data.mapper.TestMapper.selectByPrimaryKey ### The error occurred while executing a query ### Cause: java.lang.NullPointerException] with root cause java.lang.NullPointerException: null ``` 我的pom.xml ``` <!-- Spring Boot Mybatis--> <dependency> <groupId>org.mybatis.spring.boot</groupId> <artifactId>mybatis-spring-boot-starter</artifactId> <version>1.3.2</version> </dependency> <!-- 数据源 --> <dependency> <groupId>com.alibaba</groupId> <artifactId>druid</artifactId> <version>1.0.19</version> </dependency> <!-- MySQL--> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>5.1.39</version> </dependency> ``` TestMapper.java代码 ``` TestConfig selectByPrimaryKey(Long id); ``` TestMapper.xml ``` <select id="selectByPrimaryKey" resultMap="BaseResultMap" parameterType="java.lang.Long" > select <include refid="Base_Column_List" /> from test_config where id = #{id,jdbcType=BIGINT} </select> ``` 请各位大神帮忙看一下,几乎所有查询都报这个错误,用了@Param 注释也不行
java多模块maven整合spring boot+mybatis
我在一个项目中建了多个模块,他们属于maven, (1)Login(登录模块), (2)Register(注册模块), (3)PassWord(密码模块), (4)Certification(认证模块), (5)Commons(公共模块)。 这几个模块中都有Controller、Service、model、repository 层。 这样的项目该怎么去整合springboot和mybatis?
spring boot mybatis的问题
spring boot版本1.5.3.RELEASE mybatis-spring-boot-starter版本1.1.1 pom.xml文件 ``` <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>1.5.3.RELEASE</version> </parent> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-jdbc</artifactId> </dependency> <dependency> <groupId>org.mybatis.spring.boot</groupId> <artifactId>mybatis-spring-boot-starter</artifactId> <version>1.1.1</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> </dependency> </dependencies> ``` test测试类 ``` @RunWith(SpringJUnit4ClassRunner.class) @SpringBootTest(classes=Run.class) public class DaoTest { @Autowired private Dao dao; @Test public void insertPeople(){ People people = new People(); people.setName("张三"); people.setAge(23); Integer i = dao.insertPeople(people); System.out.println("插入数量"+i); } } ``` 错误信息 ``` org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'DaoTest': Unsatisfied dependency expressed through field 'dao'; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'demo.repository.Dao' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)} at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:588) ~[spring-beans-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88) ~[spring-beans-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:366) ~[spring-beans-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1264) ~[spring-beans-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireBeanProperties(AbstractAutowireCapableBeanFactory.java:386) ~[spring-beans-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.injectDependencies(DependencyInjectionTestExecutionListener.java:118) ~[spring-test-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.prepareTestInstance(DependencyInjectionTestExecutionListener.java:83) ~[spring-test-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.boot.test.autoconfigure.SpringBootDependencyInjectionTestExecutionListener.prepareTestInstance(SpringBootDependencyInjectionTestExecutionListener.java:44) ~[spring-boot-test-autoconfigure-1.5.3.RELEASE.jar:1.5.3.RELEASE] at org.springframework.test.context.TestContextManager.prepareTestInstance(TestContextManager.java:230) ~[spring-test-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.createTest(SpringJUnit4ClassRunner.java:228) [spring-test-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.test.context.junit4.SpringJUnit4ClassRunner$1.runReflectiveCall(SpringJUnit4ClassRunner.java:287) [spring-test-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12) [junit-4.12.jar:4.12] at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.methodBlock(SpringJUnit4ClassRunner.java:289) [spring-test-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:247) [spring-test-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:94) [spring-test-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290) [junit-4.12.jar:4.12] at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71) [junit-4.12.jar:4.12] at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288) [junit-4.12.jar:4.12] at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58) [junit-4.12.jar:4.12] at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268) [junit-4.12.jar:4.12] at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61) [spring-test-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70) [spring-test-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.junit.runners.ParentRunner.run(ParentRunner.java:363) [junit-4.12.jar:4.12] at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:191) [spring-test-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:86) [.cp/:na] at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38) [.cp/:na] at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:459) [.cp/:na] at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:675) [.cp/:na] at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:382) [.cp/:na] at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:192) [.cp/:na] Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'demo.repository.Dao' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)} at org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoMatchingBeanFound(DefaultListableBeanFactory.java:1486) ~[spring-beans-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1104) ~[spring-beans-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1066) ~[spring-beans-4.3.8.RELEASE.jar:4.3.8.RELEASE] at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:585) ~[spring-beans-4.3.8.RELEASE.jar:4.3.8.RELEASE] ... 29 common frames omitted ``` **可是当我将mybatis-spring-boot-starter版本改为1.0.1后测试却可以通过** ``` 2017-05-27 11:22:55.458 INFO 10388 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**/favicon.ico] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler] 2017-05-27 11:22:55.753 INFO 10388 --- [ main] DaoTest : Started DaoTest in 3.123 seconds (JVM running for 3.778) 插入数量1 2017-05-27 11:22:56.404 INFO 10388 --- [ Thread-2] o.s.w.c.s.GenericWebApplicationContext : Closing org.springframework.web.context.support.GenericWebApplicationContext@7690781: startup date [Sat May 27 11:22:53 CST 2017]; root of context hierarchy ``` 然后我又将mybatis-spring-boot-starter版本改为1.3.0,同样上面的错误,应该是dao无法创建bean,这是为什么?????
gradle+spring boot+mybatis+PageHelper 分页无效
被折磨了一天,网上也找了很多解决办法,都不行,求助大神 如果PageHelper 降版本到4.0的话,PageInfo里的属性就全是空的, 直接用PageHelper.startPage(1, 2); 也没用。 ,不废话,直接上代码。 测试类: ``` @RunWith(SpringRunner.class) @SpringBootTest public class UserMappertest { @Autowired private UserMapper userMapper; @Test public void getAllByPage(){ Map<String,Object> map = new HashMap<String,Object>(); map.put("email", "a"); // map.put("id", "2"); PageHelper.startPage(1, 2,true);// 默认从第一页开始,每页五条 List<Map<String,Object>> users = userMapper.getAllByPage(map); PageInfo<Map<String,Object>> pageBlog = new PageInfo<Map<String,Object>>(users);// 将查出来的blogArticleList绑定到pageInfo中 System.out.println(">======page====>"+pageBlog.toString()); int a = 1; for(Map<String,Object> m:users) { System.out.println(">============users===a====>"+a); System.out.println(">============users===username====>"+m.get("username")); a++; } } } ``` 输出结果: ``` >======page====>PageInfo{pageNum=1, pageSize=7, size=7, startRow=0, endRow=6, total=7, pages=1, list=[{password=$76NoUnuTJ8iAtKIUi, name=qweq,id=1, avatar=//localhost:8081/view/5a9f9509c99a7138a8ea306c, email=i@om, username=admin}, {password=$2a$IUi, name=Wu, id=2, avatar=//localhost:8081/view/5a9f962ec99a7138a8ea306d, email=wa@wa.com, username=wau}, {password=$2a$1O7s3Jo4XW, name=是释放, id=3, avatar=//localhost:8081/view/5a9f9684c99a7138a8ea306e, email=12321@sfa.cn, username=wjy0703}, {password=123456, name=fs士大夫撒, id=4, avatar=//localhost:8081/view/5aa777c3c99a715b60793591, email=safdaf@ssfdsa.com, username=wjy}, {password=$2EXdOSDS, name=发大好时光, id=6, avatar=//localhost:8081/view/5aa77a8cc99a715b60793592, email=123212@sfa.cn, username=wjiyu}, {password=123456, name=搭顺风很舒服, id=7, email=safdafaaa@ssfdsa.com, username=qwe123}, {password=$2QB6cdbsAySst80C9FS, name=safddasfa, id=9, email=fas2f@sfa.com, username=abc123}], prePage=0, nextPage=0, isFirstPage=true, isLastPage=true, hasPreviousPage=false, hasNextPage=false, navigatePages=8, navigateFirstPage=1, navigateLastPage=1, navigatepageNums=[1]} >============users===a====>1 >============users===username====>admin >============users===a====>2 >============users===username====>waylau >============users===a====>3 >============users===username====>wjy0703 >============users===a====>4 >============users===username====>wjy >============users===a====>5 >============users===username====>wayu >============users===a====>6 >============users===username====>qwe123 >============users===a====>7 >============users===username====>abc123 ``` gradle配置 springBootVersion = '1.5.2.RELEASE': ``` // 添加 MySQL连接驱动 的依赖 compile('mysql:mysql-connector-java:6.0.5') // 添加 Apache Commons Lang 依赖 compile('org.apache.commons:commons-lang3:3.5') //mybatis依赖 compile('org.mybatis.spring.boot:mybatis-spring-boot-starter:1.3.0') //pagehelper依赖 compile('com.github.pagehelper:pagehelper:5.1.2') ``` mybatis-config.xml 配置: 下面使用"com.github.pagehelper.PageHelper"也不行,都不报错,也不能分页。 ``` <?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN" "http://mybatis.org/dtd/mybatis-3-config.dtd"> <configuration> <typeAliases> <typeAlias alias="Integer" type="java.lang.Integer" /> <typeAlias alias="Long" type="java.lang.Long" /> <typeAlias alias="HashMap" type="java.util.HashMap" /> <typeAlias alias="LinkedHashMap" type="java.util.LinkedHashMap" /> <typeAlias alias="ArrayList" type="java.util.ArrayList" /> <typeAlias alias="LinkedList" type="java.util.LinkedList" /> </typeAliases> <plugins> <plugin interceptor="com.github.pagehelper.PageInterceptor"> </plugin> </plugins> </configuration> ``` application.properties 配置: ``` #Thymeleaf spring.thymeleaf.encoding=UTF-8 #热部署静态文件 spring.thymeleaf.cache=false #使用HTML5标准 spring.thymeleaf.mode=HTML5 #DataSource spring.datasource.url=jdbc:mysql://localhost/boot?useSSL=false&serverTimezone=UTC&characterEncoding=utf-8 spring.datasource.username=boot spring.datasource.password=boot spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver # 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