1 /*
2 * Copyright (c) 2015, 2016, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package java.net.http;
27
28 import java.io.IOException;
29 import java.nio.ByteBuffer;
30
31 /**
32 * When sending a frame, the length field must be set in sub-class
33 * by calling computeLength()
34 */
35 abstract class Http2Frame {
36
37 int length = -1;
38 int type;
39 int streamid;
40 int flags;
41
42 // called when reading in only
43 void initCommon(int length, int type, int streamid, int flags) {
44 this.length = length;
45 this.type = type;
46 this.streamid = streamid;
47 this.flags = flags;
48 }
49
50 public int length() {
51 return length;
52 }
53
54 public int type() {
55 return type;
56 }
57
58 public int streamid() {
59 return streamid;
60 }
61
62 public void setFlag(int flag) {
63 flags |= flag;
64 }
65
66 public void setFlags(int flags) {
67 this.flags = flags;
68 }
69
70 public int getFlags() {
71 return flags;
72 }
73
74 public boolean getFlag(int flag) {
75 return (flags & flag) != 0;
76 }
77
78 public void clearFlag(int flag) {
79 flags &= 0xffffffff ^ flag;
80 }
81
82 public void streamid(int streamid) {
83 this.streamid = streamid;
84 }
85
86 abstract void readIncomingImpl(ByteBufferConsumer bc) throws IOException;
87
88 /**
89 * assume given array contains at least one complete frame.
90 */
91 static Http2Frame readIncoming(ByteBufferConsumer bc) throws IOException {
92 int x = bc.getInt();
93 int length = x >> 8;
94 int type = x & 0xff;
95 int flags = bc.getByte();
96 int streamid = bc.getInt();
97 Http2Frame f = null;
98 switch (type) {
99 case DataFrame.TYPE:
100 f = new DataFrame();
101 break;
102 case HeadersFrame.TYPE:
103 f = new HeadersFrame();
104 break;
105 case ContinuationFrame.TYPE:
106 f = new ContinuationFrame();
107 break;
108 case ResetFrame.TYPE:
109 f = new ResetFrame();
110 break;
111 case PriorityFrame.TYPE:
112 f = new PriorityFrame();
113 break;
114 case SettingsFrame.TYPE:
115 f = new SettingsFrame();
116 break;
117 case GoAwayFrame.TYPE:
118 f = new GoAwayFrame();
119 break;
120 case PingFrame.TYPE:
121 f = new PingFrame();
122 break;
123 case PushPromiseFrame.TYPE:
124 f = new PushPromiseFrame();
125 break;
126 case WindowUpdateFrame.TYPE:
127 f = new WindowUpdateFrame();
128 break;
129 default:
130 String msg = Integer.toString(type);
131 throw new IOException("unknown frame type " + msg);
132 }
133 f.initCommon(length, type, streamid, flags);
134 f.readIncomingImpl(bc);
135 return f;
136 }
137
138 public String typeAsString() {
139 return asString(this.type);
140 }
141
142 public static String asString(int type) {
143 switch (type) {
144 case DataFrame.TYPE:
145 return "DATA";
146 case HeadersFrame.TYPE:
147 return "HEADERS";
148 case ContinuationFrame.TYPE:
149 return "CONTINUATION";
150 case ResetFrame.TYPE:
151 return "RESET";
152 case PriorityFrame.TYPE:
153 return "PRIORITY";
154 case SettingsFrame.TYPE:
155 return "SETTINGS";
156 case GoAwayFrame.TYPE:
157 return "GOAWAY";
158 case PingFrame.TYPE:
159 return "PING";
160 case PushPromiseFrame.TYPE:
161 return "PUSH_PROMISE";
162 case WindowUpdateFrame.TYPE:
163 return "WINDOW_UPDATE";
164 default:
165 return "UNKNOWN";
166 }
167 }
168
169 @Override
170 public String toString() {
171 StringBuilder sb = new StringBuilder();
172 sb.append(typeAsString())
173 .append(": length=")
174 .append(Integer.toString(length))
175 .append(", streamid=")
176 .append(streamid)
177 .append(", flags=");
178
179 int f = flags;
180 int i = 0;
181 if (f == 0) {
182 sb.append("0 ");
183 } else {
184 while (f != 0) {
185 if ((f & 1) == 1) {
186 sb.append(flagAsString(1 << i))
187 .append(' ');
188 }
189 f = f >> 1;
190 i++;
191 }
192 }
193 return sb.toString();
194 }
195
196 // Override
197 String flagAsString(int f) {
198 return "unknown";
199 }
200
201 abstract void computeLength();
202
203 void writeOutgoing(ByteBufferGenerator bg) {
204 if (length == -1) {
205 throw new InternalError("Length not set on outgoing frame");
206 }
207 ByteBuffer buf = bg.getBuffer(9);
208 int x = (length << 8) + type;
209 buf.putInt(x);
210 buf.put((byte)flags);
211 buf.putInt(streamid);
212 }
213 }