Question

我使用以下依赖项，并且我还注册了Hibernate4Module，虽然我为延迟加载实体获取了延迟初始化异常。

  Spring :  4.1
  Hibernate : 4.3
  jackson-datatype-hibernate4 : 2.4.2
  jackson-databind : 2.4.2

我的ObjectMapper子类

public class HibernateAwareObjectMapper extends ObjectMapper {
    public HibernateAwareObjectMapper() {
        registerModule(new Hibernate4Module());
     }
    }

和我在应用程序上下文文件中的配置

   <mvc:annotation-driven>
      <mvc:message-converters>
          <!-- Use the HibernateAware mapper instead of the default -->
          <bean class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter">
              <property name="objectMapper">
                  <bean class="utils.HibernateAwareObjectMapper" />
              </property>
          </bean>
      </mvc:message-converters>
  </mvc:annotation-driven>



public class ProductUsageViewModel {
 private ProductUsage productUsage;

 public String getCollectionNumber() {
   return productUsage.getProduct().getCollectionNumber();
 }


// some other methods 

}

@Entity
@Audited
@JsonIdentityInfo(generator=ObjectIdGenerators.IntSequenceGenerator.class, property="@id")
public class Product implements ModificationTracker {

  @Id
  @GeneratedValue(strategy = GenerationType.AUTO)
  @Column(nullable = false)
  private Long id;

  // A product may not have a corresponding sample. Some products may be
  // imported from another location. In such a case the corresponding collection
  // field is allowed to be null.
  @CollectedSampleExists
  @ManyToOne(optional=true, fetch=FetchType.LAZY)
  private CollectedSample collectedSample;

  public String getCollectionNumber() {
    if (collectedSample == null)
      return null;
    return collectedSample.getCollectionNumber();
  }

 }






 @Entity
    public class CollectedSample implements ModificationTracker, Comparable<CollectedSample> {

  @Id
  @GeneratedValue(strategy = GenerationType.AUTO)
  @Column(nullable=false)
  private Long id;


  @Column(length=20, unique=true)
  @Index(name="collectedSample_collectionNumber_index")
  private String collectionNumber;

  public String getCollectionNumber() {
    return collectionNumber;
  }


}

堆栈跟踪

org.springframework.http.converter.HttpMessageNotWritableException：无法写入内容：无法初始化代理 - 无会话（通过参考链：java.util.HashMap [＆＃34; usage＆＃34;] - ＆gt; viewmodel。 ProductUsageViewModel [＆＃34; collectionNumber＆＃34;]）;嵌套异常是com.fasterxml.jackson.databind.JsonMappingException：无法初始化代理 - 没有Session（通过引用链：java.util.HashMap [＆＃34; usage＆＃34;] - ＆gt; viewmodel.ProductUsageViewModel [＆＃34] ; collectionNumber＆＃34;]）在org.springframework.http.converter.json.AbstractJackson2HttpMessageConverter.writeInternal（AbstractJackson2HttpMessageConverter.java:238）在org.springframework.http.converter.AbstractHttpMessageConverter.write（AbstractHttpMessageConverter.java:208）在org.springframework.web.servlet.mvc.method.annotation.AbstractMessageConverterMethodProcessor.writeWithMessageConverters（AbstractMessageConverterMethodProcessor.java:153）在org.springframework.web.servlet.mvc.method.annotation.HttpEntityMethodProcessor.handleReturnValue（HttpEntityMethodProcessor.java:138）在org.springframework.web.method.support.HandlerMethodReturnValueHandlerComposite.handleReturnValue（HandlerMethodReturnValueHandlerComposite.java:71）在org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle（ServletInvocableHandlerMethod.java:122）在org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod（RequestMappingHandlerAdapter.java:781）在org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal（RequestMappingHandlerAdapter.java:721）在org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle（AbstractHandlerMethodAdapter.java:83）在org.springframework.web.servlet.DispatcherServlet.doDispatch（DispatcherServlet.java:943）在org.springframework.web.servlet.DispatcherServlet.doService（DispatcherServlet.java:877）在org.springframework.web.servlet.FrameworkServlet.processRequest（FrameworkServlet.java:961）在org.springframework.web.servlet.FrameworkServlet.doPost（FrameworkServlet.java:863）在javax.servlet.http.HttpServlet.service（HttpServlet.java:646）在org.springframework.web.servlet.FrameworkServlet.service（FrameworkServlet.java:837）在javax.servlet.http.HttpServlet.service（HttpServlet.java:727）在org.apache.catalina.core.ApplicationFilterChain.internalDoFilter（ApplicationFilterChain.java:303）在org.apache.catalina.core.ApplicationFilterChain.doFilter（ApplicationFilterChain.java:208）在org.apache.tomcat.websocket.server.WsFilter.doFilter（WsFilter.java:52）在org.apache.catalina.core.ApplicationFilterChain.internalDoFilter（ApplicationFilterChain.java:241）在org.apache.catalina.core.ApplicationFilterChain.doFilter（ApplicationFilterChain.java:208）在org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:330）在org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke（FilterSecurityInterceptor.java:118）在org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter（FilterSecurityInterceptor.java:84）在org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:342）在org.springframework.security.web.access.ExceptionTranslationFilter.doFilter（ExceptionTranslationFilter.java:113）在org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:342）在org.springframework.security.web.session.SessionManagementFilter.doFilter（SessionManagementFilter.java:103）在org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:342）在org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter（AnonymousAuthenticationFilter.java:113）在org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:342）在org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter（SecurityContextHolderAwareRequestFilter.java:154）在org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:342）在org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter（RequestCacheAwareFilter.java:45）在org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:342）在org.springframework.security.web.authentication.www.BasicAuthenticationFilter.doFilter（BasicAuthenticationFilter.java:150）在org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:342）在org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter.doFilterInternal（WebAsyncManagerIntegrationFilter.java:50）在org.springframework.web.filter.OncePerRequestFilter.doFilter（OncePerRequestFilter.java:107）在org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:342）在org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter（SecurityContextPersistenceFilter.java:87）在org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:342）在org.springframework.security.web.FilterChainProxy.doFilterInternal（FilterChainProxy.java:192）在org.springframework.security.web.FilterChainProxy.doFilter（FilterChainProxy.java:160）在org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate（DelegatingFilterProxy.java:344）在org.springframework.web.filter.DelegatingFilterProxy.doFilter（DelegatingFilterProxy.java:261）在org.apache.catalina.core.ApplicationFilterChain.internalDoFilter（ApplicationFilterChain.java:241）在org.apache.catalina.core.ApplicationFilterChain.doFilter（ApplicationFilterChain.java:208）在CORSFilter.doFilter（CORSFilter.java:25）在org.apache.catalina.core.ApplicationFilterChain.internalDoFilter（ApplicationFilterChain.java:241）在org.apache.catalina.core.ApplicationFilterChain.doFilter（ApplicationFilterChain.java:208）在org.apache.catalina.core.StandardWrapperValve.invoke（StandardWrapperValve.java:220）在org.apache.catalina.core.StandardContextValve.invoke（StandardContextValve.java:122）在org.apache.catalina.authenticator.AuthenticatorBase.invoke（AuthenticatorBase.java:501）在org.apache.catalina.core.StandardHostValve.invoke（StandardHostValve.java:170） at org.apache.catalina.valves.ErrorReportValve.invoke（ErrorReportValve.java:98）在org.apache.catalina.valves.AccessLogValve.invoke（AccessLogValve.java:950）在org.apache.catalina.core.StandardEngineValve.invoke（StandardEngineValve.java:116）在org.apache.catalina.connector.CoyoteAdapter.service（CoyoteAdapter.java:408）在org.apache.coyote.http11.AbstractHttp11Processor.process（AbstractHttp11Processor.java:1040） at org.apache.coyote.AbstractProtocol $ AbstractConnectionHandler.process（AbstractProtocol.java:607）在org.apache.tomcat.util.net.JIoEndpoint $ SocketProcessor.run（JIoEndpoint.java:313） at java.util.concurrent.ThreadPoolExecutor.runWorker（Unknown Source） at java.util.concurrent.ThreadPoolExecutor $ Worker.run（Unknown Source）在java.lang.Thread.run（未知来源）引起：com.fasterxml.jackson.databind.JsonMappingException：无法初始化代理 - 没有Session（通过引用链：java.util.HashMap [＆＃34; usage＆＃34;] - ＆gt; viewmodel.ProductUsageViewModel [＆＃34] ; collectionNumber＆＃34;]）

任何人都可以帮我摆脱那个例外，请...

JsonMappingException：无法初始化代理 - 没有通过引用链的Session

0 个答案: