| /** |
| * 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.oncrpc; |
| |
| /** |
| * Represent an RPC message as defined in RFC 1831. |
| */ |
| public abstract class RpcMessage { |
| /** Message type */ |
| public static enum Type { |
| // the order of the values below are significant. |
| RPC_CALL, |
| RPC_REPLY; |
| |
| public int getValue() { |
| return ordinal(); |
| } |
| |
| public static Type fromValue(int value) { |
| if (value < 0 || value >= values().length) { |
| return null; |
| } |
| return values()[value]; |
| } |
| } |
| |
| protected final int xid; |
| protected final Type messageType; |
| |
| RpcMessage(int xid, Type messageType) { |
| if (messageType != Type.RPC_CALL && messageType != Type.RPC_REPLY) { |
| throw new IllegalArgumentException("Invalid message type " + messageType); |
| } |
| this.xid = xid; |
| this.messageType = messageType; |
| } |
| |
| public abstract XDR write(XDR xdr); |
| |
| public int getXid() { |
| return xid; |
| } |
| |
| public Type getMessageType() { |
| return messageType; |
| } |
| |
| protected void validateMessageType(Type expected) { |
| if (expected != messageType) { |
| throw new IllegalArgumentException("Message type is expected to be " |
| + expected + " but got " + messageType); |
| } |
| } |
| } |