1 /*
2 * Copyright 2010 The Apache Software Foundation
3 *
4 * Licensed to the Apache Software Foundation (ASF) under one
5 * or more contributor license agreements. See the NOTICE file
6 * distributed with this work for additional information
7 * regarding copyright ownership. The ASF licenses this file
8 * to you under the Apache License, Version 2.0 (the
9 * "License"); you may not use this file except in compliance
10 * with the License. You may obtain a copy of the License at
11 *
12 * http://www.apache.org/licenses/LICENSE-2.0
13 *
14 * Unless required by applicable law or agreed to in writing, software
15 * distributed under the License is distributed on an "AS IS" BASIS,
16 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
17 * See the License for the specific language governing permissions and
18 * limitations under the License.
19 */
20 package org.apache.hadoop.hbase.ipc;
21
22 import java.io.DataInput;
23 import java.io.DataOutput;
24 import java.io.IOException;
25
26 import org.apache.hadoop.io.Text;
27 import org.apache.hadoop.io.Writable;
28 import org.apache.hadoop.hbase.security.User;
29
30 /**
31 * The IPC connection header sent by the client to the server
32 * on connection establishment.
33 */
34 class ConnectionHeader implements Writable {
35 protected String protocol;
36
37 public ConnectionHeader() {}
38
39 /**
40 * Create a new {@link ConnectionHeader} with the given <code>protocol</code>
41 * and {@link User}.
42 * @param protocol protocol used for communication between the IPC client
43 * and the server
44 * @param user {@link User} of the client communicating with
45 * the server
46 */
47 public ConnectionHeader(String protocol, User user) {
48 this.protocol = protocol;
49 }
50
51 @Override
52 public void readFields(DataInput in) throws IOException {
53 protocol = Text.readString(in);
54 if (protocol.isEmpty()) {
55 protocol = null;
56 }
57 }
58
59 @Override
60 public void write(DataOutput out) throws IOException {
61 Text.writeString(out, (protocol == null) ? "" : protocol);
62 }
63
64 public String getProtocol() {
65 return protocol;
66 }
67
68 public User getUser() {
69 return null;
70 }
71
72 public String toString() {
73 return protocol;
74 }
75 }