是否有可能在JAX-RS/JAXB webservice中捕获SAXParseException？

Question

我想检查一个JAX-RS webservice请求，它包含正文中的有效XML。但是，此代码：

@PUT 
@Produces(MediaType.TEXT_XML) 
@Consumes(MediaType.TEXT_XML) 
@Path("/{objectID}") 
public MyObject updateMyObject(@PathParam("objectID") String existingObjectID, JAXBElement<MyObject> object) 
{ 
    MyObject udpatedObject = null; 

    try 
    { 
     udpatedObject = object.getValue(); 
    } 
    catch (Throwable ex) 
    { 
     throw new WebApplicationException(Response.Status.BAD_REQUEST);    
    } 

    // carry one with processing 
} 

返回500内部服务器错误，而不是预期的400错误。有没有办法捕捉异常？

的异常堆栈跟踪的起点是：

Local Exception Stack: 
Exception [EclipseLink-25004] (Eclipse Persistence Services - 2.0.1.v20100213-r6600): org.eclipse.persistence.exceptions.XMLMarshalException 
Exception Description: An error occurred unmarshalling the document 
Internal Exception: org.xml.sax.SAXParseException: Premature end of file. 
at org.eclipse.persistence.exceptions.XMLMarshalException.unmarshalException(XMLMarshalException.java:92) 

Answer 1

您可以使用异常映射。当异常被抛出将被转换成一个响应代码：

import javax.persistence.NoResultException; 
import javax.ws.rs.core.Response; 
import javax.ws.rs.ext.ExceptionMapper; 
import javax.ws.rs.ext.Provider; 

@Provider 
public class XMLMarshalExceptionMapper implements ExceptionMapper<XMLMarshalException> { 

    public Response toResponse(XMLMarshalException exception) { 
     return Response.status(Response.Status.BAD_REQUEST).build(); 
    } 

} 

参考：

• https://jsr311.dev.java.net/nonav/javadoc/javax/ws/rs/ext/ExceptionMapper.html