/dubbo-rpc/dubbo-rpc-api/src/main/java/com/alibaba/dubbo/rpc/filter/CompatibleFilter.java

/*

 * Copyright 1999-2011 Alibaba Group.

 *  

 * 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.alibaba.dubbo.rpc.filter;



import java.lang.reflect.Method;

import java.lang.reflect.Type;



import com.alibaba.dubbo.common.Constants;

import com.alibaba.dubbo.common.logger.Logger;

import com.alibaba.dubbo.common.logger.LoggerFactory;

import com.alibaba.dubbo.common.utils.CompatibleTypeUtils;

import com.alibaba.dubbo.common.utils.PojoUtils;

import com.alibaba.dubbo.rpc.Filter;

import com.alibaba.dubbo.rpc.Invocation;

import com.alibaba.dubbo.rpc.Invoker;

import com.alibaba.dubbo.rpc.Result;

import com.alibaba.dubbo.rpc.RpcException;

import com.alibaba.dubbo.rpc.RpcResult;



/**

 * CompatibleFilter

 * 

 * @author william.liangf

 */

public class CompatibleFilter implements Filter {

    

    private static Logger logger = LoggerFactory.getLogger(CompatibleFilter.class);



    public Result invoke(Invoker<?> invoker, Invocation invocation) throws RpcException {

        Result result = invoker.invoke(invocation);

        if (! invocation.getMethodName().startsWith("$") && ! result.hasException()) {

            Object value = result.getValue();

            if (value != null) {

                try {

                    Method method = invoker.getInterface().getMethod(invocation.getMethodName(), invocation.getParameterTypes());

                    Class<?> type = method.getReturnType();

                    Object newValue;

                    String serialization = invoker.getUrl().getParameter(Constants.SERIALIZATION_KEY); 

                    if ("json".equals(serialization)

                            || "fastjson".equals(serialization)){

                        Type gtype = method.getGenericReturnType();

                        newValue = PojoUtils.realize(value, type, gtype);

                    } else if (! type.isInstance(value)) {

                        newValue = PojoUtils.isPojo(type)

                            ? PojoUtils.realize(value, type) 

                            : CompatibleTypeUtils.compatibleTypeConvert(value, type);

                        

                    } else {

                        newValue = value;

                    }

                    if (newValue != value) {

                        result = new RpcResult(newValue);

                    }

                } catch (Throwable t) {

                    logger.warn(t.getMessage(), t);

                }

            }

        }

        return result;

    }



}