RESTEasy + spring，未发现异常未被映射器捕获

Question

我有一些休息资源可以很好地工作但是当我对一个无效的URL进行REST调用时，JBoss会返回一个404 html异常。我想将其更改为JSON异常响应。我尝试过创建映射器，但控件没有到达那里。我正在为ref。添加我的映射器代码。

@Provider
@Produces(MediaType.APPLICATION_JSON)
public class NotFoundExceptionMapper implements ExceptionMapper<NotFoundException> {

/**
 * Map an exception to a {@link javax.ws.rs.core.Response}.
 *
 * @param exception the exception to map to a response.
 * @return a response mapped from the supplied exception.
 */
@Override
public Response toResponse(final NotFoundException exception) {
    Map<String, Object> info = new HashMap<>();
    info.put("msg", exception.getMessage());
    info.put("date", new Date());
    info.put("details", "The requested resource hasn't been found");

    return Response
            .status(Response.Status.INTERNAL_SERVER_ERROR)
            .entity(info)
            .type(MediaType.APPLICATION_JSON)
            .build();
}

Answer 1

您可以通过多种不同的方式注册@Provider注释类：

1. Resteasy自动扫描为ServletContextListener。
2. 在web.xml中显式配置为ServletContextListener。
3. 明确配置为独立javax.ws.rs.Application。
4. 由像Spring这样的IOC容器自动扫描。

由Resteasy自动扫描

通过设置@Provider上下文参数，将您的应用程序配置为自动扫描web.xml文件中的resteasy.scan.providers带注释的类。

<web-app>
   <listener>
      <listener-class>
         org.jboss.resteasy.plugins.server.servlet.ResteasyBootstrap
      </listener-class>
   </listener>

    <context-param>
        <param-name>resteasy.scan.providers</param-name>
        <param-value>true</param-value>
    </context-param>

   <servlet>
      <servlet-name>Resteasy</servlet-name>
      <servlet-class>
         org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher
      </servlet-class>
   </servlet>

   <servlet-mapping>
      <servlet-name>Resteasy</servlet-name>
      <url-pattern>/resteasy/*</url-pattern>
   </servlet-mapping>

</web-app>

注意：如果要在JBoss 7或更高版本上部署，请不要使用此选项。在JBoss的版本7及更高版本中自动启用@Provider，并且使用此值可能会在应用程序启动期间导致错误。

---

在web.xml中显式配置

通过设置resteasy.providers上下文参数，可以在web.xml文件中向Resteasy显式注册提供者。

<web-app>

    <context-param>
        <param-name>resteasy.providers</param-name>
        <param-value>com.foo.NotFoundExceptionMapper,com.foo.SomeOtherProvider</param-value>
    </context-param>

   ... All of the other HttpServletDispatcher and ResteasyBootstrap stuff like above.
</web-app>

---

显式配置为独立应用

如果您使用javax.ws.rs.Application类引导Resteasy服务，可以按如下方式添加提供程序实现：

 public class FooApplication extends Application
 {
     private Set<Object> singletons = new HashSet<Object>();
     private Set<Class> classes = new HashSet<Class>();

     public FooApplication()
     { 
         classes.put(NotFoundExceptionMapper.class);
     }

     public Set<Class<?>> getClasses()
     {
         return classes;
     }

     public Set<Object> getSingletons()
     {
         return singletons;
     }
 }

Spring自动扫描

如果您使用Spring扫描您的Resteasy提供程序，您需要告诉Spring您对@Provider注释感兴趣，并且您需要配置Spring以告诉Resteasy它已扫描的bean。

<强> ExceptionMapper

您需要向提供者添加@Component注释，以便Spring知道扫描它。

@Component
@Provider
@Produces(MediaType.APPLICATION_JSON)
public class NotFoundExceptionMapper implements ExceptionMapper<NotFoundException> 
{
   //Implementation removed for brevity...
}

<强> Web.xml中

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="3.0"
         xmlns="http://java.sun.com/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd">

    <!-- Spring Configuration -->
    <context-param>
        <param-name>contextClass</param-name>
        <param-value>org.springframework.web.context.support.AnnotationConfigWebApplicationContext</param-value>
    </context-param>

    <context-param>
       <param-name>contextConfigLocation</param-name>
       <param-value>com.foo.SpringConfig</param-value>
    </context-param>

    <!-- RESTEasy Configuration -->
    <listener>
        <listener-class>org.jboss.resteasy.plugins.server.servlet.ResteasyBootstrap</listener-class>
    </listener>

    <context-param>
        <param-name>resteasy.servlet.mapping.prefix</param-name>
        <param-value>/v1</param-value>
    </context-param>

    <!-- RESTEasy <-> Spring Connector (Needed so that RESTEasy has access to Spring managed beans!) -->
    <listener>
        <listener-class>org.jboss.resteasy.plugins.spring.SpringContextLoaderListener</listener-class>
    </listener>

    <!-- RESTEasy HTTP Request Processor Servlet -->
    <servlet>
        <servlet-name>resteasy-servlet</servlet-name>
        <servlet-class>org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher</servlet-class>
    </servlet>

    <servlet-mapping>
        <servlet-name>resteasy-servlet</servlet-name>
        <url-pattern>/v1/*</url-pattern>
    </servlet-mapping>

</web-app>