customfaulthandler.java

Xfire文件 用于开发web service 的一个开源工具 很好用的

package org.codehaus.xfire.handler;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.Iterator;

import javax.xml.stream.XMLStreamException;

import org.codehaus.xfire.MessageContext;
import org.codehaus.xfire.XFireRuntimeException;
import org.codehaus.xfire.fault.FaultInfoException;
import org.codehaus.xfire.fault.XFireFault;
import org.codehaus.xfire.service.FaultInfo;
import org.codehaus.xfire.service.MessagePartInfo;
import org.codehaus.xfire.service.OperationInfo;
import org.codehaus.xfire.service.binding.AbstractBinding;
import org.codehaus.xfire.util.stax.JDOMStreamWriter;

/**
 * Builds up a custom detail element from an exception.
 * 
 * @author <a href="mailto:[e-mail]">Dan Diephouse</a>
 */
public class CustomFaultHandler
    extends AbstractHandler
{    
    
    public CustomFaultHandler() {
        super();
        setPhase(Phase.USER);
    }

    public void invoke(MessageContext context)
        throws Exception
    {
        XFireFault fault = (XFireFault) context.getExchange().getFaultMessage().getBody();
        
        Throwable cause = fault.getCause();
        OperationInfo op = null;
        
        if (context.getExchange() != null) 
            op = context.getExchange().getOperation();

        if (cause == null || op == null)
            return;

        FaultInfo faultPart = getFaultForClass(op, cause.getClass());

        if (faultPart != null)
        {
            handleFault(context, fault, cause, (MessagePartInfo) faultPart.getMessageParts().get(0));
        }
    }

    protected void handleFault(MessageContext context, XFireFault fault, Throwable cause, MessagePartInfo faultPart)
        throws XFireFault
    {
        JDOMStreamWriter writer = new JDOMStreamWriter(fault.getDetail());
        
        Object faultBean = getFaultBean(cause, faultPart, context);
        
        try
        {
            AbstractBinding.writeParameter(writer, context, faultBean, faultPart, faultPart.getName().getNamespaceURI());
        }
        catch (XMLStreamException e)
        {
            throw new XFireFault("Could not write to outgoing stream.", e, XFireFault.RECEIVER);
        }
    }

    protected Object getFaultBean(Throwable cause, MessagePartInfo faultPart, MessageContext context) 
    {
        if (FaultInfoException.class.isAssignableFrom(cause.getClass()))
        {
            try
            {
                Method method = cause.getClass().getMethod("getFaultInfo", new Class[0]);
                return method.invoke(cause, new Object[0]);
            }
            catch (InvocationTargetException e)
            {
                throw new XFireRuntimeException("Couldn't invoke getFaultInfo method.", e);
            }
            catch (NoSuchMethodException e)
            {
                throw new XFireRuntimeException("Custom faults need a getFaultInfo method.", e);
            }
            catch (Exception e)
            {
                throw new XFireRuntimeException("Couldn't access getFaultInfo method.", e);
            }
        }
        return cause;
    }

    /**
     * Find the correct Fault part for a particular exception.
     * @param op
     * @param class1
     * @return
     */
    public FaultInfo getFaultForClass(OperationInfo op, Class class1)
    {
        for (Iterator itr = op.getFaults().iterator(); itr.hasNext();)
        {
            FaultInfo faultInfo = (FaultInfo) itr.next();
            
            if (faultInfo.getExceptionClass().isAssignableFrom(class1))
            {
                return faultInfo;
            }
        }
        
        return null;
    }
}