"Spring annotations Error" using controller as background to the foreground Ajax interaction data error

Controller as the background and the foreground of the Ajax interaction, the back-end method processing completed return a Boolean value, want to pass to the foreground to determine whether the execution succeeds, but, the problem comes:

1 Critical: Servlet.service () for Servlet rest threw exception2 java.lang.IllegalArgumentException:Unknown return value type [Java.lang.Boolean]3 At org.springframework.util.Assert.notNull (assert.java:112)4 At Org.springframework.web.method.support.HandlerMethodReturnValueHandlerComposite.handleReturnValue ( HANDLERMETHODRETURNVALUEHANDLERCOMPOSITE.JAVA:70)5 At Org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle ( servletinvocablehandlermethod.java:126)6 At Org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod ( requestmappinghandleradapter.java:777)7 At org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal ( requestmappinghandleradapter.java:706)8 At Org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle ( abstracthandlermethodadapter.java:85)9 At Org.springframework.web.servlet.DispatcherServlet.doDispatch (dispatcherservlet.java:943)Ten At Org.springframework.web.servlet.DispatcherServlet.doService (dispatcherservlet.java:877) One At org.springframework.web.servlet.FrameworkServlet.processRequest (frameworkservlet.java:966) A At org.springframework.web.servlet.FrameworkServlet.doPost (frameworkservlet.java:868) - At Javax.servlet.http.HttpServlet.service (httpservlet.java:643) - At Org.springframework.web.servlet.FrameworkServlet.service (frameworkservlet.java:842) the At Javax.servlet.http.HttpServlet.service (httpservlet.java:723) - At Org.apache.catalina.core.ApplicationFilterChain.internalDoFilter (applicationfilterchain.java:290) - At Org.apache.catalina.core.ApplicationFilterChain.doFilter (applicationfilterchain.java:206) - At Com.agen.util.LoginFilter.doFilter (loginfilter.java:58) + At Org.apache.catalina.core.ApplicationFilterChain.internalDoFilter (applicationfilterchain.java:235) - At Org.apache.catalina.core.ApplicationFilterChain.doFilter (applicationfilterchain.java:206) + At org.springframework.orm.hibernate4.support.OpenSessionInViewFilter.doFilterInternal ( opensessioninviewfilter.java:150) A At Org.springframework.web.filter.OncePerRequestFilter.doFilter (onceperrequestfilter.java:107) at At Org.apache.catalina.core.ApplicationFilterChain.internalDoFilter (applicationfilterchain.java:235) - At Org.apache.catalina.core.ApplicationFilterChain.doFilter (applicationfilterchain.java:206) - At org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal (characterencodingfilter.java:88)  - At Org.springframework.web.filter.OncePerRequestFilter.doFilter (onceperrequestfilter.java:107) - At Org.apache.catalina.core.ApplicationFilterChain.internalDoFilter (applicationfilterchain.java:235) - At Org.apache.catalina.core.ApplicationFilterChain.doFilter (applicationfilterchain.java:206) in At Org.apache.catalina.core.StandardWrapperValve.invoke (standardwrappervalve.java:233) - At Org.apache.catalina.core.StandardContextValve.invoke (standardcontextvalve.java:191) to At Org.apache.catalina.core.StandardHostValve.invoke (standardhostvalve.java:127) + At Org.apache.catalina.valves.ErrorReportValve.invoke (errorreportvalve.java:103) - At Org.apache.catalina.core.StandardEngineValve.invoke (standardenginevalve.java:109) the At Org.apache.catalina.connector.CoyoteAdapter.service (coyoteadapter.java:293) * At org.apache.coyote.http11.Http11AprProcessor.process (http11aprprocessor.java:879) $ At org.apache.coyote.http11.http11aprprotocol$http11connectionhandler.process (http11aprprotocol.java:617) Panax Notoginseng At Org.apache.tomcat.util.net.aprendpoint$worker.run (aprendpoint.java:1778) -At Java.lang.Thread.run (Unknown Source)

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The controller code for the moment is this:

1@RequestMapping ("/productadd")2     3      Public BooleanProductadd (product product) {4 Product.setproductid (Uuid.randomuuid (). toString ());5Criteria = Getcurrentsession (). Createcriteria (Product.class);6Criteria.setprojection (Projections.max ("Productorder"));7Integer ProductOrder2 =Productservice.uniqueresultint (criteria);8Integer procuctorder=1;9         if(ProductOrder2 = =NULL){Ten Product.setproductorder (procuctorder); One}Else{ Aproductorder2++; - Product.setproductorder (productOrder2); -         } the Productservice.save (product); -         return true; -}

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Problem:

Now the controller can only recognize the return of true as a string, that is, the URL to find the corresponding page, but where there are URLs like this.

Analyze the problem:

And we want this to be true as the return value to the foreground of the Ajax to judge, if true to insert a successful prompt and so on, so we do not want this true as a URL to return, but as the JSON format of the data back to the foreground

Workaround :

We need to add a spring annotation to this method and let the method return a JSON data to the foreground this annotation is: @ResponseBody

1@RequestMapping ("/productadd")2 @ResponseBody3      Public BooleanProductadd (product product) {4 Product.setproductid (Uuid.randomuuid (). toString ());5Criteria = Getcurrentsession (). Createcriteria (Product.class);6Criteria.setprojection (Projections.max ("Productorder"));7Integer ProductOrder2 =Productservice.uniqueresultint (criteria);8Integer procuctorder=1;9         if(ProductOrder2 = =NULL){Ten Product.setproductorder (procuctorder); One}Else{ Aproductorder2++; - Product.setproductorder (productOrder2); -         } the Productservice.save (product); -         return true; -}

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This allows you to return true as JSON data to the foreground.

"Spring annotations Error" using controller as background to the foreground Ajax interaction data error