相信小伙伴们一定遇到过这种错误，
1 八月 26, 2020 11:32:32 上午 org.apache.catalina.core.StandardWrapperValve invoke 2 严重: Servlet.service() for servlet [springmvc] in context with path [] threw exception [Request processing failed; nested exception is java.lang.IllegalStateException: Optional int parameter 'pageindex' is present but cannot be translated into a null value due to being declared as a primitive type. Consider declaring it as object wrapper for the corresponding primitive type.] with root cause 3 java.lang.IllegalStateException: Optional int parameter 'pageindex' is present but cannot be translated into a null value due to being declared as a primitive type. Consider declaring it as object wrapper for the corresponding primitive type. 4 at org.springframework.web.method.annotation.AbstractNamedValueMethodArgumentResolver.handleNullValue(AbstractNamedValueMethodArgumentResolver.java:245) 5 at org.springframework.web.method.annotation.AbstractNamedValueMethodArgumentResolver.resolveArgument(AbstractNamedValueMethodArgumentResolver.java:116) 6 at org.springframework.web.method.support.HandlerMethodArgumentResolverComposite.resolveArgument(HandlerMethodArgumentResolverComposite.java:121) 7 at org.springframework.web.method.support.InvocableHandlerMethod.getMethodArgumentValues(InvocableHandlerMethod.java:167) 8 at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:134) 9 at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:105) 10 at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:879) 11 at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:793) 12 at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) 13 at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1040) 14 at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:943) 15 at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006) 16 at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:898) 17 at javax.servlet.http.HttpServlet.service(HttpServlet.java:624) 18 at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883) 19 at javax.servlet.http.HttpServlet.service(HttpServlet.java:731) 20 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303) 21 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) 22 at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) 23 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) 24 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) 25 at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201) 26 at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) 27 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) 28 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) 29 at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:218) 30 at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:110) 31 at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:506) 32 at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:169) 33 at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103) 34 at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:962) 35 at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116) 36 at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:445) 37 at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1115) 38 at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:637) 39 at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.doRun(AprEndpoint.java:2549) 40 at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.run(AprEndpoint.java:2538) 41 at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) 42 at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) 43 at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) 44 at java.lang.Thread.run(Thread.java:745) 45 46 八月 26, 2020 11:36:20 上午 org.apache.catalina.core.ApplicationContext log 47 信息: Destroying Spring FrameworkServlet 'springmvc' 48 八月 26, 2020 11:36:21 上午 org.apache.catalina.core.ApplicationContext log 49 信息: No Spring WebApplicationInitializer types detected on classpath 50 八月 26, 2020 11:36:30 上午 org.apache.catalina.core.ApplicationContext log 51 信息: Initializing Spring DispatcherServlet 'springmvc' 52 八月 26, 2020 11:36:38 上午 org.apache.catalina.core.StandardWrapperValve invoke 53 严重: Servlet.service() for servlet [springmvc] in context with path [] threw exception [Request processing failed; nested exception is java.lang.NullPointerException] with root cause 54 java.lang.NullPointerException 55 at com.bdqn.controller.UserController.touserlist(UserController.java:66) 56 at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 57 at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) 58 at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) 59 at java.lang.reflect.Method.invoke(Method.java:498) 60 at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:190) 61 at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:138) 62 at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:105) 63 at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:879) 64 at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:793) 65 at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) 66 at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1040) 67 at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:943) 68 at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006) 69 at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:898) 70 at javax.servlet.http.HttpServlet.service(HttpServlet.java:624) 71 at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883) 72 at javax.servlet.http.HttpServlet.service(HttpServlet.java:731) 73 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303) 74 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) 75 at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) 76 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) 77 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) 78 at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201) 79 at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) 80 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) 81 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) 82 at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:218) 83 at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:110) 84 at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:506) 85 at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:169) 86 at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103) 87 at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:962) 88 at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116) 89 at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:445) 90 at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1115) 91 at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:637) 92 at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.doRun(AprEndpoint.java:2549) 93 at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.run(AprEndpoint.java:2538) 94 at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) 95 at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) 96 at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) 97 at java.lang.Thread.run(Thread.java:745) 98 99 八月 26, 2020 11:38:13 上午 org.apache.catalina.core.ApplicationContext log 100 信息: Destroying Spring FrameworkServlet 'springmvc' 101 八月 26, 2020 11:38:14 上午 org.apache.catalina.core.ApplicationContext log 102 信息: No Spring WebApplicationInitializer types detected on classpath 103 八月 26, 2020 11:38:45 上午 org.apache.catalina.core.ApplicationContext log 104 信息: No Spring WebApplicationInitializer types detected on classpath 105 八月 26, 2020 11:38:47 上午 org.apache.catalina.core.ApplicationContext log 106 信息: Initializing Spring DispatcherServlet 'springmvc' 107 八月 26, 2020 11:38:48 上午 org.apache.catalina.core.StandardWrapperValve invoke 108 严重: Servlet.service() for servlet [springmvc] in context with path [] threw exception [Request processing failed; nested exception is java.lang.IllegalStateException: Optional int parameter 'pageindex' is present but cannot be translated into a null value due to being declared as a primitive type. Consider declaring it as object wrapper for the corresponding primitive type.] with root cause 109 java.lang.IllegalStateException: Optional int parameter 'pageindex' is present but cannot be translated into a null value due to being declared as a primitive type. Consider declaring it as object wrapper for the corresponding primitive type. 110 at org.springframework.web.method.annotation.AbstractNamedValueMethodArgumentResolver.handleNullValue(AbstractNamedValueMethodArgumentResolver.java:245) 111 at org.springframework.web.method.annotation.AbstractNamedValueMethodArgumentResolver.resolveArgument(AbstractNamedValueMethodArgumentResolver.java:116) 112 at org.springframework.web.method.support.HandlerMethodArgumentResolverComposite.resolveArgument(HandlerMethodArgumentResolverComposite.java:121) 113 at org.springframework.web.method.support.InvocableHandlerMethod.getMethodArgumentValues(InvocableHandlerMethod.java:167) 114 at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:134) 115 at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:105) 116 at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:879) 117 at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:793) 118 at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) 119 at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1040) 120 at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:943) 121 at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006) 122 at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:898) 123 at javax.servlet.http.HttpServlet.service(HttpServlet.java:624) 124 at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883) 125 at javax.servlet.http.HttpServlet.service(HttpServlet.java:731) 126 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303) 127 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) 128 at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) 129 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) 130 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) 131 at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201) 132 at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) 133 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) 134 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) 135 at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:218) 136 at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:110) 137 at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:506) 138 at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:169) 139 at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103) 140 at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:962) 141 at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116) 142 at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:445) 143 at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1115) 144 at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:637) 145 at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.doRun(AprEndpoint.java:2549) 146 at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.run(AprEndpoint.java:2538) 147 at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) 148 at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) 149 at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) 150 at java.lang.Thread.run(Thread.java:745)
下面就与大家分享错误报告以及解决方法把
认真分析 ，就能捕捉到关键错误
parameter 'pageindex'
代表controller方法中的参数出现错误
所以小伙伴们可以仔细检查最开始进方法的时候，参数是否为空 以及参数名是否一致，还有是否允许必填
如图就是我更改后的
required表示是否必填，多用于方法最开始进入防止出现空指针
到最后我们还是发现还是报错，
最后我们可以仔细看到，pageindex 类型为int 该原类型是不支持为空 所以改成 Integer即可解决