jsonrpcresult.java

json-rpc是和DWR类似的ajax-rpc实现。我比较细化

/*
 * JSON-RPC-Java - a JSON-RPC to Java Bridge with dynamic invocation
 *
 * $Id: JSONRPCResult.java,v 1.8.2.1 2006/03/06 12:39:21 mclark Exp $
 *
 * Copyright Metaparadigm Pte. Ltd. 2004.
 * Michael Clark <[e-mail]>
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */

package com.metaparadigm.jsonrpc;

import java.io.CharArrayWriter;
import java.io.PrintWriter;
import org.json.JSONObject;

public class JSONRPCResult {

    private Object result = null;
    private Object id = null;
    private int errorCode;

    public final static int CODE_SUCCESS = 0;
    public final static int CODE_REMOTE_EXCEPTION = 490;
    public final static int CODE_ERR_PARSE = 590;
    public final static int CODE_ERR_NOMETHOD = 591;
    public final static int CODE_ERR_UNMARSHALL = 592;
    public final static int CODE_ERR_MARSHALL = 593;

    public final static String MSG_ERR_PARSE =
	"couldn't parse request arguments";
    public final static String MSG_ERR_NOMETHOD =
	"method not found (session may have timed out)";

    public JSONRPCResult(int errorCode, Object id, Object o)
    {
	this.errorCode = errorCode;
	this.id = id;
	this.result = o;
    }

    public Object getResult() { return result; }
    public Object getId() { return id; }
    public int getErrorCode() { return errorCode; }

    public String toString()
    {
	JSONObject o = new JSONObject();
	if(errorCode == CODE_SUCCESS) {
	    o.put("id", id);
	    o.put("result", result);
	} else if (errorCode == CODE_REMOTE_EXCEPTION) {
	    Throwable e = (Throwable)result;
	    CharArrayWriter caw = new CharArrayWriter();
	    e.printStackTrace(new PrintWriter(caw));
	    JSONObject err = new JSONObject();
	    err.put("code", new Integer(errorCode));
	    err.put("msg", e.getMessage());
	    err.put("trace", caw.toString());
	    o.put("id", id);
	    o.put("error", err);
	} else {
	    JSONObject err = new JSONObject();
	    err.put("code", new Integer(errorCode));
	    err.put("msg", result);
	    o.put("id", id);
	    o.put("error", err);
	}
	return o.toString();
    }
}