我有一个简单的POJO“问候”，用JAXB注释，我试图从Java Restful服务返回XML。但是，每当我试图访问网页时，POJO都没有成功转换为XML。我的日志中出现错误，我收到了Http 406：
o.s.w.s.m.a.AnnotationMethodHandlerExceptionResolver - Resolving exception from handler [GreetingController@20b722]: org.springframework.web.HttpMediaTypeNotAcceptableException: Could not find acceptable representation
我可以返回一个简单的String，但是当我尝试返回我的POJO时，它会出错。
我正在使用Spring-MVC结构。
Greeting.java：
import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlRootElement;
@XmlRootElement
public class Greeting {
private String id;
private String content;
public Greeting() {
}
public void setId(String id) {
this.id = id;
}
@XmlElement
public String getId() {
return id;
}
public void setContent(String content) {
this.content = content;
}
@XmlElement
public String getContent() {
return content;
}
}
控制器：
@Controller
@RequestMapping("/greeting")
public class GreetingController {
protected final Logger log = LoggerFactory.getLogger(GreetingController.class);
private static final String template = "Hello, %s!";
private static Random rand = new Random();
//Returns correct string
@RequestMapping(method = RequestMethod.GET, value="/goodbye", headers="Accept=application/xml")
public @ResponseBody String letsReturnAString() {
log.info("Entered letsReturnAString()");
return "Curses, Foiled Again!";
}
//Returns Http 406
@RequestMapping(method = RequestMethod.GET, headers="Accept=application/xml")
public @ResponseBody Greeting greeting() {
log.info("Entered greeting()");
Greeting g = new Greeting();
g.setId(rand.nextInt(99999999) +"");
g.setContent(String.format(template, "NAME"));
return g;
}
}
context.xml中：
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:security="http://www.springframework.org/schema/security"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:oxm="http://www.springframework.org/schema/oxm"
xmlns:mvc="http://www.springframework.org/schema/tx"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsd
http://www.springframework.org/schema/oxm http://www.springframework.org/schema/oxm/spring-oxm-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/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.1.xsd">
<context:component-scan base-package="com.package" />
<mvc:annotation-driven/>
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix">
<value>/WEB-INF/pages/</value>
</property>
<property name="suffix">
<value>.jsp</value>
</property>
</bean>
<bean class="org.springframework.web.servlet.view.ContentNegotiatingViewResolver">
<property name="mediaTypes">
<map>
<entry key="html" value="text/html"></entry>
<entry key="json" value="application/json"></entry>
<entry key="xml" value="application/xml"></entry>
</map>
</property>
<property name="viewResolvers">
<list>
<bean class="org.springframework.web.servlet.view.UrlBasedViewResolver">
<property name="viewClass" value="org.springframework.web.servlet.view.JstlView"></property>
<property name="prefix" value="/WEB-INF/jsp/"></property>
<property name="suffix" value=".jsp"></property>
</bean>
</list>
</property>
</bean>
</beans>
与点击页面相关的完整错误日志：
DEBUG o.s.security.web.FilterChainProxy - /greeting at position 1 of 12 in additional filter chain; firing Filter: 'ChannelProcessingFilter'
DEBUG o.s.s.web.util.AntPathRequestMatcher - Request '/greeting' matched by universal pattern '/**'
DEBUG o.s.s.w.a.c.ChannelProcessingFilter - Request: FilterInvocation: URL: /greeting; ConfigAttributes: [ANY_CHANNEL]
DEBUG o.s.security.web.FilterChainProxy - /greeting at position 2 of 12 in additional filter chain; firing Filter: 'SecurityContextPersistenceFilter'
DEBUG o.s.s.w.c.HttpSessionSecurityContextRepository - No HttpSession currently exists
DEBUG o.s.s.w.c.HttpSessionSecurityContextRepository - No SecurityContext was available from the HttpSession: null. A new one will be created.
DEBUG o.s.security.web.FilterChainProxy - /greeting at position 3 of 12 in additional filter chain; firing Filter: 'LogoutFilter'
DEBUG o.s.security.web.FilterChainProxy - /greeting at position 4 of 12 in additional filter chain; firing Filter: 'UsernamePasswordAuthenticationFilter'
DEBUG o.s.security.web.FilterChainProxy - /greeting at position 5 of 12 in additional filter chain; firing Filter: 'DefaultLoginPageGeneratingFilter'
DEBUG o.s.security.web.FilterChainProxy - /greeting at position 6 of 12 in additional filter chain; firing Filter: 'BasicAuthenticationFilter'
DEBUG o.s.security.web.FilterChainProxy - /greeting at position 7 of 12 in additional filter chain; firing Filter: 'RequestCacheAwareFilter'
DEBUG o.s.security.web.FilterChainProxy - /greeting at position 8 of 12 in additional filter chain; firing Filter: 'SecurityContextHolderAwareRequestFilter'
DEBUG o.s.security.web.FilterChainProxy - /greeting at position 9 of 12 in additional filter chain; firing Filter: 'AnonymousAuthenticationFilter'
DEBUG o.s.s.w.a.AnonymousAuthenticationFilter - Populated SecurityContextHolder with anonymous token: 'org.springframework.security.authentication.AnonymousAuthenticationToken@9055c2bc: Principal: anonymousUser; Credentials: [PROTECTED]; Authenticated: true; Details: org.springframework.security.web.authentication.WebAuthenticationDetails@b364: RemoteIpAddress: 0:0:0:0:0:0:0:1; SessionId: null; Granted Authorities: ROLE_ANONYMOUS'
DEBUG o.s.security.web.FilterChainProxy - /greeting at position 10 of 12 in additional filter chain; firing Filter: 'SessionManagementFilter'
DEBUG o.s.security.web.FilterChainProxy - /greeting at position 11 of 12 in additional filter chain; firing Filter: 'ExceptionTranslationFilter'
DEBUG o.s.security.web.FilterChainProxy - /greeting at position 12 of 12 in additional filter chain; firing Filter: 'FilterSecurityInterceptor'
DEBUG o.s.s.web.util.AntPathRequestMatcher - Checking match of request : '/greeting'; against '/welcome*'
DEBUG o.s.s.w.a.i.FilterSecurityInterceptor - Secure object: FilterInvocation: URL: /greeting; Attributes: [IS_AUTHENTICATED_ANONYMOUSLY]
DEBUG o.s.s.w.a.i.FilterSecurityInterceptor - Previously Authenticated: org.springframework.security.authentication.AnonymousAuthenticationToken@9055c2bc: Principal: anonymousUser; Credentials: [PROTECTED]; Authenticated: true; Details: org.springframework.security.web.authentication.WebAuthenticationDetails@b364: RemoteIpAddress: 0:0:0:0:0:0:0:1; SessionId: null; Granted Authorities: ROLE_ANONYMOUS
DEBUG o.s.s.access.vote.AffirmativeBased - Voter: org.springframework.security.access.vote.RoleVoter@84fdbc, returned: 0
DEBUG o.s.s.access.vote.AffirmativeBased - Voter: org.springframework.security.access.vote.AuthenticatedVoter@12e5c94, returned: 1
DEBUG o.s.s.w.a.i.FilterSecurityInterceptor - Authorization successful
DEBUG o.s.s.w.a.i.FilterSecurityInterceptor - RunAsManager did not change Authentication object
DEBUG o.s.security.web.FilterChainProxy - /greeting reached end of additional filter chain; proceeding with original chain
DEBUG o.s.web.servlet.DispatcherServlet - DispatcherServlet with name 'spring-tutorial' processing GET request for [/SpringMVC/greeting]
DEBUG o.s.w.s.m.a.DefaultAnnotationHandlerMapping - Mapping [/greeting] to HandlerExecutionChain with handler [com.package.controller.GreetingController@20b722] and 1 interceptor
DEBUG o.s.web.servlet.DispatcherServlet - Last-Modified value for [/SpringMVC/greeting] is: -1
DEBUG o.s.w.b.a.s.HandlerMethodInvoker - Invoking request handler method: public com.package.form.Greeting com.package.controller.GreetingController.greeting()
INFO c.s.controller.GreetingController - Entered greeting()
DEBUG o.s.w.s.m.a.AnnotationMethodHandlerExceptionResolver - Resolving exception from handler [com.package.controller.GreetingController@20b722]: org.springframework.web.HttpMediaTypeNotAcceptableException: Could not find acceptable representation
DEBUG o.s.w.s.m.a.ResponseStatusExceptionResolver - Resolving exception from handler [com.package.controller.GreetingController@20b722]: org.springframework.web.HttpMediaTypeNotAcceptableException: Could not find acceptable representation
DEBUG o.s.w.s.m.s.DefaultHandlerExceptionResolver - Resolving exception from handler [com.package.controller.GreetingController@20b722]: org.springframework.web.HttpMediaTypeNotAcceptableException: Could not find acceptable representation
DEBUG o.s.s.w.c.HttpSessionSecurityContextRepository - SecurityContext is empty or contents are anonymous - context will not be stored in HttpSession.
DEBUG o.s.web.servlet.DispatcherServlet - Null ModelAndView returned to DispatcherServlet with name 'spring-tutorial': assuming HandlerAdapter completed request handling
DEBUG o.s.web.servlet.DispatcherServlet - Successfully completed request
DEBUG o.s.s.w.a.ExceptionTranslationFilter - Chain processed normally
DEBUG o.s.s.w.c.SecurityContextPersistenceFilter - SecurityContextHolder now cleared, as request processing completed
答案 0 :(得分：1)
我发现了我的问题。我正在使用<mvc:annotation-driven/>但是，我用于mvc的架构不对。
xmlns:mvc="http://www.springframework.org/schema/tx"
不是正确的架构。一旦我把它改成了正确的，一切都很好。适当的架构：
xmlns:mvc="http://www.springframework.org/schema/mvc"
答案 1 :(得分：0)
不确定这是否是您的问题，但由于您要注释字段（实例变量）而不是属性（get或set方法），因此您需要使用@XmlAccessorType(XmlAccessType.FIELD)注释您的类。如果你不这样做，JAXB将抛出一个“重复属性”异常，这可能表现为你所看到的问题。