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20 package org.apache.mina.filter.codec;
21
22 import org.apache.mina.common.ByteBuffer;
23 import org.apache.mina.common.ByteBufferProxy;
24 import org.apache.mina.common.IoFilter;
25 import org.apache.mina.common.IoFilterAdapter;
26 import org.apache.mina.common.IoFilterChain;
27 import org.apache.mina.common.IoSession;
28 import org.apache.mina.common.WriteFuture;
29 import org.apache.mina.common.support.DefaultWriteFuture;
30 import org.apache.mina.filter.codec.support.SimpleProtocolDecoderOutput;
31 import org.apache.mina.filter.codec.support.SimpleProtocolEncoderOutput;
32 import org.apache.mina.util.SessionLog;
33
34
35
36
37
38
39
40
41
42 public class ProtocolCodecFilter extends IoFilterAdapter {
43 public static final String ENCODER = ProtocolCodecFilter.class.getName()
44 + ".encoder";
45
46 public static final String DECODER = ProtocolCodecFilter.class.getName()
47 + ".decoder";
48
49 private static final String DECODER_OUT = ProtocolCodecFilter.class.getName()
50 + ".decoderOut";
51
52 private static final Class[] EMPTY_PARAMS = new Class[0];
53
54 private static final ByteBuffer EMPTY_BUFFER = ByteBuffer.wrap(new byte[0]);
55
56 private final ProtocolCodecFactory factory;
57
58 public ProtocolCodecFilter(ProtocolCodecFactory factory) {
59 if (factory == null) {
60 throw new NullPointerException("factory");
61 }
62 this.factory = factory;
63 }
64
65 public ProtocolCodecFilter(final ProtocolEncoder encoder,
66 final ProtocolDecoder decoder) {
67 if (encoder == null) {
68 throw new NullPointerException("encoder");
69 }
70 if (decoder == null) {
71 throw new NullPointerException("decoder");
72 }
73
74 this.factory = new ProtocolCodecFactory() {
75 public ProtocolEncoder getEncoder() {
76 return encoder;
77 }
78
79 public ProtocolDecoder getDecoder() {
80 return decoder;
81 }
82 };
83 }
84
85 public ProtocolCodecFilter(final Class encoderClass,
86 final Class decoderClass) {
87 if (encoderClass == null) {
88 throw new NullPointerException("encoderClass");
89 }
90 if (decoderClass == null) {
91 throw new NullPointerException("decoderClass");
92 }
93 if (!ProtocolEncoder.class.isAssignableFrom(encoderClass)) {
94 throw new IllegalArgumentException("encoderClass: "
95 + encoderClass.getName());
96 }
97 if (!ProtocolDecoder.class.isAssignableFrom(decoderClass)) {
98 throw new IllegalArgumentException("decoderClass: "
99 + decoderClass.getName());
100 }
101 try {
102 encoderClass.getConstructor(EMPTY_PARAMS);
103 } catch (NoSuchMethodException e) {
104 throw new IllegalArgumentException(
105 "encoderClass doesn't have a public default constructor.");
106 }
107 try {
108 decoderClass.getConstructor(EMPTY_PARAMS);
109 } catch (NoSuchMethodException e) {
110 throw new IllegalArgumentException(
111 "decoderClass doesn't have a public default constructor.");
112 }
113
114 this.factory = new ProtocolCodecFactory() {
115 public ProtocolEncoder getEncoder() throws Exception {
116 return (ProtocolEncoder) encoderClass.newInstance();
117 }
118
119 public ProtocolDecoder getDecoder() throws Exception {
120 return (ProtocolDecoder) decoderClass.newInstance();
121 }
122 };
123 }
124
125 public void onPreAdd(IoFilterChain parent, String name,
126 NextFilter nextFilter) throws Exception {
127 if (parent.contains(ProtocolCodecFilter.class)) {
128 throw new IllegalStateException(
129 "A filter chain cannot contain more than one ProtocolCodecFilter.");
130 }
131 }
132
133 public void onPostRemove(IoFilterChain parent, String name,
134 NextFilter nextFilter) throws Exception {
135 disposeEncoder(parent.getSession());
136 disposeDecoder(parent.getSession());
137 disposeDecoderOut(parent.getSession());
138 }
139
140 public void messageReceived(NextFilter nextFilter, IoSession session,
141 Object message) throws Exception {
142 if (!(message instanceof ByteBuffer)) {
143 nextFilter.messageReceived(session, message);
144 return;
145 }
146
147 ByteBuffer in = (ByteBuffer) message;
148 ProtocolDecoder decoder = getDecoder(session);
149 ProtocolDecoderOutput decoderOut = getDecoderOut(session, nextFilter);
150
151 int oldPos = in.position();
152 try {
153 synchronized (decoderOut) {
154 decoder.decode(session, in, decoderOut);
155 }
156 } catch (Throwable t) {
157 ProtocolDecoderException pde;
158 if (t instanceof ProtocolDecoderException) {
159 pde = (ProtocolDecoderException) t;
160 } else {
161 pde = new ProtocolDecoderException(t);
162 }
163
164 if (pde.getHexdump() == null) {
165 int curPos = in.position();
166 in.position(oldPos);
167 pde.setHexdump(in.getHexDump());
168 in.position(curPos);
169 }
170 throw pde;
171 } finally {
172 try {
173
174 in.release();
175 } finally {
176 decoderOut.flush();
177 }
178 }
179 }
180
181 public void messageSent(NextFilter nextFilter, IoSession session,
182 Object message) throws Exception {
183 if (message instanceof HiddenByteBuffer) {
184 return;
185 }
186
187 if (!(message instanceof MessageByteBuffer)) {
188 nextFilter.messageSent(session, message);
189 return;
190 }
191
192 nextFilter.messageSent(session, ((MessageByteBuffer) message).message);
193 }
194
195 public void filterWrite(NextFilter nextFilter, IoSession session,
196 WriteRequest writeRequest) throws Exception {
197 Object message = writeRequest.getMessage();
198 if (message instanceof ByteBuffer) {
199 nextFilter.filterWrite(session, writeRequest);
200 return;
201 }
202
203 ProtocolEncoder encoder = getEncoder(session);
204 ProtocolEncoderOutputImpl encoderOut = getEncoderOut(session,
205 nextFilter, writeRequest);
206
207 try {
208 encoder.encode(session, message, encoderOut);
209 encoderOut.flush();
210 nextFilter.filterWrite(session, new WriteRequest(
211 new MessageByteBuffer(writeRequest.getMessage()),
212 writeRequest.getFuture(), writeRequest.getDestination()));
213 } catch (Throwable t) {
214 ProtocolEncoderException pee;
215 if (t instanceof ProtocolEncoderException) {
216 pee = (ProtocolEncoderException) t;
217 } else {
218 pee = new ProtocolEncoderException(t);
219 }
220 throw pee;
221 }
222 }
223
224 public void sessionClosed(NextFilter nextFilter, IoSession session)
225 throws Exception {
226
227 ProtocolDecoder decoder = getDecoder(session);
228 ProtocolDecoderOutput decoderOut = getDecoderOut(session, nextFilter);
229 try {
230 decoder.finishDecode(session, decoderOut);
231 } catch (Throwable t) {
232 ProtocolDecoderException pde;
233 if (t instanceof ProtocolDecoderException) {
234 pde = (ProtocolDecoderException) t;
235 } else {
236 pde = new ProtocolDecoderException(t);
237 }
238 throw pde;
239 } finally {
240
241 disposeEncoder(session);
242 disposeDecoder(session);
243 disposeDecoderOut(session);
244 decoderOut.flush();
245 }
246
247 nextFilter.sessionClosed(session);
248 }
249
250 private ProtocolEncoder getEncoder(IoSession session) throws Exception {
251 ProtocolEncoder encoder = (ProtocolEncoder) session
252 .getAttribute(ENCODER);
253 if (encoder == null) {
254 encoder = factory.getEncoder();
255 session.setAttribute(ENCODER, encoder);
256 }
257 return encoder;
258 }
259
260 private ProtocolEncoderOutputImpl getEncoderOut(IoSession session,
261 NextFilter nextFilter, WriteRequest writeRequest) {
262 return new ProtocolEncoderOutputImpl(session, nextFilter, writeRequest);
263 }
264
265 private ProtocolDecoder getDecoder(IoSession session) throws Exception {
266 ProtocolDecoder decoder = (ProtocolDecoder) session
267 .getAttribute(DECODER);
268 if (decoder == null) {
269 decoder = factory.getDecoder();
270 session.setAttribute(DECODER, decoder);
271 }
272 return decoder;
273 }
274
275 private ProtocolDecoderOutput getDecoderOut(IoSession session,
276 NextFilter nextFilter) {
277 ProtocolDecoderOutput out = (ProtocolDecoderOutput) session.getAttribute(DECODER_OUT);
278 if (out == null) {
279 out = new SimpleProtocolDecoderOutput(session, nextFilter);
280 session.setAttribute(DECODER_OUT, out);
281 }
282
283 return out;
284 }
285
286 private void disposeEncoder(IoSession session) {
287 ProtocolEncoder encoder = (ProtocolEncoder) session
288 .removeAttribute(ENCODER);
289 if (encoder == null) {
290 return;
291 }
292
293 try {
294 encoder.dispose(session);
295 } catch (Throwable t) {
296 SessionLog.warn(session, "Failed to dispose: "
297 + encoder.getClass().getName() + " (" + encoder + ')');
298 }
299 }
300
301 private void disposeDecoder(IoSession session) {
302 ProtocolDecoder decoder = (ProtocolDecoder) session
303 .removeAttribute(DECODER);
304 if (decoder == null) {
305 return;
306 }
307
308 try {
309 decoder.dispose(session);
310 } catch (Throwable t) {
311 SessionLog.warn(session, "Falied to dispose: "
312 + decoder.getClass().getName() + " (" + decoder + ')');
313 }
314 }
315
316 private void disposeDecoderOut(IoSession session) {
317 session.removeAttribute(DECODER_OUT);
318 }
319
320 private static class HiddenByteBuffer extends ByteBufferProxy {
321 private HiddenByteBuffer(ByteBuffer buf) {
322 super(buf);
323 }
324 }
325
326 private static class MessageByteBuffer extends ByteBufferProxy {
327 private final Object message;
328
329 private MessageByteBuffer(Object message) {
330 super(EMPTY_BUFFER);
331 this.message = message;
332 }
333
334 public void acquire() {
335
336 }
337
338 public void release() {
339
340 }
341 }
342
343 private static class ProtocolEncoderOutputImpl extends
344 SimpleProtocolEncoderOutput {
345 private final IoSession session;
346
347 private final NextFilter nextFilter;
348
349 private final WriteRequest writeRequest;
350
351 public ProtocolEncoderOutputImpl(IoSession session,
352 NextFilter nextFilter, WriteRequest writeRequest) {
353 this.session = session;
354 this.nextFilter = nextFilter;
355 this.writeRequest = writeRequest;
356 }
357
358 protected WriteFuture doFlush(ByteBuffer buf) {
359 WriteFuture future = new DefaultWriteFuture(session);
360 nextFilter.filterWrite(session, new WriteRequest(
361 new HiddenByteBuffer(buf), future, writeRequest
362 .getDestination()));
363 return future;
364 }
365 }
366 }