### Error querying database. Cause: java.lang.NullPointerException ### Cause: java.lang.NullPointer

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#springmvc #mybatis

在尝试查询数据库时遇到了错误，错误信息提示为 'Error querying database. Cause: java.lang.NullPointerException'。这通常表示在SpringMVC和MyBatis集成的环境中，某个对象未被正确初始化导致空指针异常。

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01:12:39.634 [http-nio-8080-exec-1] DEBUG o.s.w.s.m.m.a.ExceptionHandlerExceptionResolver - Resolving exception from handler [public com.tendecss.common.R com.tendecss.controller.portal.ProductController.list(java.lang.String,java.lang.Integer,int,int,java.lang.String)]: org.mybatis.spring.MyBatisSystemException: nested exception is org.apache.ibatis.exceptions.PersistenceException: 
### Error querying database.  Cause: java.lang.NullPointerException
### Cause: java.lang.NullPointerException
01:12:39.635 [http-nio-8080-exec-1] DEBUG o.s.w.s.m.a.ResponseStatusExceptionResolver - Resolving exception from handler [public com.tendecss.common.R com.tendecss.controller.portal.ProductController.list(java.lang.String,java.lang.Integer,int,int,java.lang.String)]: org.mybatis.spring.MyBatisSystemException: nested exception is org.apache.ibatis.exceptions.PersistenceException: 
### Error querying database.  Cause: java.lang.NullPointerException
### Cause: java.lang.NullPointerException
01:12:39.636 [http-nio-8080-exec-1] DEBUG o.s.w.s.m.s.DefaultHandlerExceptionResolver - Resolving exception from handler [public com.tendecss.common.R com.tendecss.controller.portal.ProductController.list(java.lang.String,java.lang.Integer,int,int,java.lang.String)]: org.mybatis.spring.MyBatisSystemException: nested exception is org.apache.ibatis.exceptions.PersistenceException: 
### Error querying database.  Cause: java.lang.NullPointerException
### Cause: java.lang.NullPointerException
01:12:39.645 [http-nio-8080-exec-1] DEBUG o.s.web.servlet.DispatcherServlet - Could not complete request
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) ~[mybatis-spring-1.3.0.jar:1.3.0]
	at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:447) ~[mybatis-spring-1.3.0.jar:1.3.0]
	at com.sun.proxy.$Proxy26.selectList(Unknown Source) ~[na:na]
	at org.mybatis.spring.SqlSessionTemplate.selectList(SqlSessionTemplate.java:231) ~[mybatis-spring-1.3.0.jar:1.3.0]
	at org.apache.ibatis.binding.MapperMethod.executeForMany(MapperMethod.java:137) ~[mybatis-3.4.1.jar:3.4.1]
	at org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:75) ~[mybatis-3.4.1.jar:3.4.1]
	at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:53) ~[mybatis-3.4.1.jar:3.4.1]
	at com.sun.proxy.$Proxy38.selectByNameAndCategoryIds(Unknown Source) ~[na:na]
	at com.tendecss.service.impl.ProductServiceImpl.getProductByKeywordCategory(ProductServiceImpl.java:228) ~[classes/:na]
	at com.tendecss.controller.portal.ProductController.list(ProductController.java:39) ~[classes/:na]
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_144]
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_144]
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_144]
	at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_144]
	at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:222) ~[spring-web-4.1.9.RELEASE.jar:4.1.9.RELEASE]
	at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:137) ~[spring-web-4.1.9.RELEASE.jar:4.1.9.RELEASE]
	at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:110) ~[spring-webmvc-4.1.9.RELEASE.jar:4.1.9.RELEASE]
	at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:775) ~[spring-webmvc-4.1.9.RELEASE.jar:4.1.9.RELEASE]
	at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:705) ~[spring-webmvc-4.1.9.RELEASE.jar:4.1.9.RELEASE]
	at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85) ~[spring-webmvc-4.1.9.RELEASE.jar:4.1.9.RELEASE]
	at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:959) ~[spring-webmvc-4.1.9.RELEASE.jar:4.1.9.RELEASE]
	at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:893) ~[spring-webmvc-4.1.9.RELEASE.jar:4.1.9.RELEASE]
	at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:965) [spring-webmvc-4.1.9.RELEASE.jar:4.1.9.RELEASE]
	at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:867) [spring-webmvc-4.1.9.RELEASE.jar:4.1.9.RELEASE]
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:661) [servlet-api.jar:na]
	at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:841) [spring-webmvc-4.1.9.RELEASE.jar:4.1.9.RELEASE]
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:742) [servlet-api.jar:na]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) [catalina.jar:9.0.0.M20]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [catalina.jar:9.0.0.M20]
	at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) [tomcat-websocket.jar:9.0.0.M20]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [catalina.jar:9.0.0.M20]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [catalina.jar:9.0.0.M20]
	at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:85) [spring-web-4.1.9.RELEASE.jar:4.1.9.RELEASE]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.1.9.RELEASE.jar:4.1.9.RELEASE]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [catalina.jar:9.0.0.M20]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [catalina.jar:9.0.0.M20]
	at com.thetransactioncompany.cors.CORSFilter.doFilter(CORSFilter.java:209) [cors-filter-2.5.jar:2.5]
	at com.thetransactioncompany.cors.CORSFilter.doFilter(CORSFilter.java:244) [cors-filter-2.5.jar:2.5]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [catalina.jar:9.0.0.M20]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [catalina.jar:9.0.0.M20]
	at org.apache.logging.log4j.core.web.Log4jServletFilter.doFilter(Log4jServletFilter.java:66) [log4j-core-2.0-rc1.jar:2.0-rc1]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [catalina.jar:9.0.0.M20]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [catalina.jar:9.0.0.M20]
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:199) [catalina.jar:9.0.0.M20]
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) [catalina.jar:9.0.0.M20]
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:475) [catalina.jar:9.0.0.M20]
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140) [catalina.jar:9.0.0.M20]
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:80) [catalina.jar:9.0.0.M20]
	at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:624) [catalina.jar:9.0.0.M20]
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87) [catalina.jar:9.0.0.M20]
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342) [catalina.jar:9.0.0.M20]
	at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:498) [tomcat-coyote.jar:9.0.0.M20]
	at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) [tomcat-coyote.jar:9.0.0.M20]
	at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:796) [tomcat-coyote.jar:9.0.0.M20]
	at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1368) [tomcat-coyote.jar:9.0.0.M20]
	at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-coyote.jar:9.0.0.M20]
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [na:1.8.0_144]
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [na:1.8.0_144]
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-util.jar:9.0.0.M20]
	at java.lang.Thread.run(Thread.java:748) [na:1.8.0_144]
Caused by: org.apache.ibatis.exceptions.PersistenceException: 
### Error querying database.  Cause: java.lang.NullPointerException
### Cause: java.lang.NullPointerException
	at org.apache.ibatis.exceptions.ExceptionFactory.wrapException(ExceptionFactory.java:30) ~[mybatis-3.4.1.jar:3.4.1]
	at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:150) ~[mybatis-3.4.1.jar:3.4.1]
	at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:141) ~[mybatis-3.4.1.jar:3.4.1]
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_144]
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_144]
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_144]
	at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_144]
	at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:434) ~[mybatis-spring-1.3.0.jar:1.3.0]
	... 58 common frames omitted
Caused by: java.lang.NullPointerException: null
	at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:81) ~[mybatis-3.4.1.jar:3.4.1]
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_144]
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_144]
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_144]
	at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_144]
	at org.apache.ibatis.plugin.Invocation.proceed(Invocation.java:49) ~[mybatis-3.4.1.jar:3.4.1]
	at com.github.pagehelper.SqlUtil.doProcessPage(SqlUtil.java:475) ~[pagehelper-4.1.0.jar:na]
	at com.github.pagehelper.SqlUtil._processPage(SqlUtil.java:407) ~[pagehelper-4.1.0.jar:na]
	at com.github.pagehelper.SqlUtil.processPage(SqlUtil.java:374) ~[pagehelper-4.1.0.jar:na]
	at com.github.pagehelper.PageHelper.intercept(PageHelper.java:250) ~[pagehelper-4.1.0.jar:na]
	at org.apache.ibatis.plugin.Plugin.invoke(Plugin.java:61) ~[mybatis-3.4.1.jar:3.4.1]
	at com.sun.proxy.$Proxy48.query(Unknown Source) ~[na:na]
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_144]
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_144]
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_144]
	at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_144]
	at org.apache.ibatis.plugin.Invocation.proceed(Invocation.java:49) ~[mybatis-3.4.1.jar:3.4.1]
	at com.github.pagehelper.SqlUtil.doProcessPage(SqlUtil.java:475) ~[pagehelper-4.1.0.jar:na]
	at com.github.pagehelper.SqlUtil._processPage(SqlUtil.java:407) ~[pagehelper-4.1.0.jar:na]
	at com.github.pagehelper.SqlUtil.processPage(SqlUtil.java:374) ~[pagehelper-4.1.0.jar:na]
	at com.github.pagehelper.PageHelper.intercept(PageHelper.java:250) ~[pagehelper-4.1.0.jar:na]
	at org.apache.ibatis.plugin.Plugin.invoke(Plugin.java:61) ~[mybatis-3.4.1.jar:3.4.1]
	at com.sun.proxy.$Proxy48.query(Unknown Source) ~[na:na]
	at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:148) ~[mybatis-3.4.1.jar:3.4.1]
	... 64 common frames omitted
01:12:39.649 [http-nio-8080-exec-1] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Returning cached instance of singleton bean 'sqlSessionFactory'

查询语句
   List<Product> productList = productMapper.selectByNameAndCategoryIds("%手%",categoryIdList);

  <select id="selectByNameAndCategoryIds" resultMap="BaseResultMap" parameterType="map">
    SELECT
    <include refid="Base_Column_List"></include>
    from runface_product
    where status = 1
    <if test='productName != null'>
      and name like #{productName}
    </if>
    <if test='categoryIdList != null' >
      and category_id in
      <foreach item="item" index="index" open="(" separator="," close=")" collection="categoryIdList">
        #{item}
      </foreach>
    </if>
  </select>

 

tendecss
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