/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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 org.apache.hadoop.ipc;
import java.io.IOException;
/**
* Superclass of all protocols that use Hadoop RPC.
* Subclasses of this interface are also supposed to have
* a static final long versionID field.
*/
public interface VersionedProtocol {
/**
* Return protocol version corresponding to protocol interface.
* @param protocol The classname of the protocol interface
* @param clientVersion The version of the protocol that the client speaks
* @return the version that the server will speak
* @throws IOException if any IO error occurs
*/
public long getProtocolVersion(String protocol,
long clientVersion) throws IOException;
/**
* Return protocol version corresponding to protocol interface.
* @param protocol The classname of the protocol interface
* @param clientVersion The version of the protocol that the client speaks
* @param clientMethodsHash the hashcode of client protocol methods
* @return the server protocol signature containing its version and
* a list of its supported methods
* @see ProtocolSignature#getProtocolSignature(VersionedProtocol, String,
* long, int) for a default implementation
*/
public ProtocolSignature getProtocolSignature(String protocol,
long clientVersion,
int clientMethodsHash) throws IOException;
}