com.alibaba.dubbo.rpc.Result Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of dubbo2 Show documentation
The all in one project of dubbo2
The newest version!
/*
 * 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;

import java.util.Map;

/**
 * RPC invoke result. (API, Prototype, NonThreadSafe)
 * 
 * @serial Don't change the class name and package name.
 * @see com.alibaba.dubbo.rpc.Invoker#invoke(Invocation)
 * @see com.alibaba.dubbo.rpc.RpcResult
 * @author qianlei
 * @author william.liangf
 */
public interface Result {

	/**
	 * Get invoke result.
	 * 
	 * @return result. if no result return null.
	 */
	Object getValue();

	/**
	 * Get exception.
	 * 
	 * @return exception. if no exception return null.
	 */
	Throwable getException();

    /**
     * Has exception.
     * 
     * @return has exception.
     */
    boolean hasException();

    /**
     * Recreate.
     * 
     * 
     * if (hasException()) {
     *     throw getException();
     * } else {
     *     return getValue();
     * }
     * 
     * 
     * @return result.
     * @throws if has exception throw it.
     */
    Object recreate() throws Throwable;

    /**
     * @deprecated Replace to getValue()
     * @see com.alibaba.dubbo.rpc.Result#getValue()
     */
    @Deprecated
    Object getResult();


    /**
     * get attachments.
     *
     * @return attachments.
     */
    Map getAttachments();

    /**
     * get attachment by key.
     *
     * @return attachment value.
     */
    String getAttachment(String key);

    /**
     * get attachment by key with default value.
     *
     * @return attachment value.
     */
    String getAttachment(String key, String defaultValue);

}