blob: 2fdb35de49b2b626ab518ef426534111d2faeeff (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
|
/*
*
* 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.qpid.client;
import java.util.ArrayList;
import java.util.Collection;
import java.util.LinkedHashMap;
import java.util.concurrent.atomic.AtomicInteger;
public final class ChannelToSessionMap
{
private final AMQSession[] _fastAccessSessions = new AMQSession[16];
private final LinkedHashMap<Integer, AMQSession> _slowAccessSessions = new LinkedHashMap<Integer, AMQSession>();
private int _size = 0;
private static final int FAST_CHANNEL_ACCESS_MASK = 0xFFFFFFF0;
private AtomicInteger _idFactory = new AtomicInteger(0);
private int _maxChannelID;
private int _minChannelID;
public AMQSession get(int channelId)
{
if ((channelId & FAST_CHANNEL_ACCESS_MASK) == 0)
{
return _fastAccessSessions[channelId];
}
else
{
return _slowAccessSessions.get(channelId);
}
}
public AMQSession put(int channelId, AMQSession session)
{
AMQSession oldVal;
if ((channelId & FAST_CHANNEL_ACCESS_MASK) == 0)
{
oldVal = _fastAccessSessions[channelId];
_fastAccessSessions[channelId] = session;
}
else
{
oldVal = _slowAccessSessions.put(channelId, session);
}
if ((oldVal != null) && (session == null))
{
_size--;
}
else if ((oldVal == null) && (session != null))
{
_size++;
}
return session;
}
public AMQSession remove(int channelId)
{
AMQSession session;
if ((channelId & FAST_CHANNEL_ACCESS_MASK) == 0)
{
session = _fastAccessSessions[channelId];
_fastAccessSessions[channelId] = null;
}
else
{
session = _slowAccessSessions.remove(channelId);
}
if (session != null)
{
_size--;
}
return session;
}
public Collection<AMQSession> values()
{
ArrayList<AMQSession> values = new ArrayList<AMQSession>(size());
for (int i = 0; i < 16; i++)
{
if (_fastAccessSessions[i] != null)
{
values.add(_fastAccessSessions[i]);
}
}
values.addAll(_slowAccessSessions.values());
return values;
}
public int size()
{
return _size;
}
public void clear()
{
_size = 0;
_slowAccessSessions.clear();
for (int i = 0; i < 16; i++)
{
_fastAccessSessions[i] = null;
}
}
/*
* Synchronized on whole method so that we don't need to consider the
* increment-then-reset path in too much detail
*/
public synchronized int getNextChannelId()
{
int id = _minChannelID;
boolean done = false;
while (!done)
{
id = _idFactory.getAndIncrement();
if (id == _maxChannelID)
{
//go back to the start
_idFactory.set(_minChannelID);
}
if ((id & FAST_CHANNEL_ACCESS_MASK) == 0)
{
done = (_fastAccessSessions[id] == null);
}
else
{
done = (!_slowAccessSessions.keySet().contains(id));
}
}
return id;
}
public void setMaxChannelID(int maxChannelID)
{
_maxChannelID = maxChannelID;
}
public void setMinChannelID(int minChannelID)
{
_minChannelID = minChannelID;
_idFactory.set(_minChannelID);
}
}
|
