/*
* Copyright 1995-2003 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
package sun.awt.image;
import java.awt.image.*;
import java.io.InputStream;
import java.io.IOException;
import java.io.BufferedInputStream;
import java.util.Hashtable;
public abstract class InputStreamImageSource implements ImageProducer,
ImageFetchable
{
ImageConsumerQueue consumers;
ImageDecoder decoder;
ImageDecoder decoders;
boolean awaitingFetch = false;
abstract boolean checkSecurity(Object context, boolean quiet);
int countConsumers(ImageConsumerQueue cq) {
int i = 0;
while (cq != null) {
i++;
cq = cq.next;
}
return i;
}
synchronized int countConsumers() {
ImageDecoder id = decoders;
int i = countConsumers(consumers);
while (id != null) {
i += countConsumers(id.queue);
id = id.next;
}
return i;
}
public void addConsumer(ImageConsumer ic) {
addConsumer(ic, false);
}
synchronized void printQueue(ImageConsumerQueue cq, String prefix) {
while (cq != null) {
System.out.println(prefix+cq);
cq = cq.next;
}
}
synchronized void printQueues(String title) {
System.out.println(title+"[ -----------");
printQueue(consumers, " ");
for (ImageDecoder id = decoders; id != null; id = id.next) {
System.out.println(" "+id);
printQueue(id.queue, " ");
}
System.out.println("----------- ]"+title);
}
synchronized void addConsumer(ImageConsumer ic, boolean produce) {
checkSecurity(null, false);
for (ImageDecoder id = decoders; id != null; id = id.next) {
if (id.isConsumer(ic)) {
// This consumer is already being fed.
return;
}
}
ImageConsumerQueue cq = consumers;
while (cq != null && cq.consumer != ic) {
cq = cq.next;
}
if (cq == null) {
cq = new ImageConsumerQueue(this, ic);
cq.next = consumers;
consumers = cq;
} else {
if (!cq.secure) {
Object context = null;
SecurityManager security = System.getSecurityManager();
if (security != null) {
context = security.getSecurityContext();
}
if (cq.securityContext == null) {
cq.securityContext = context;
} else if (!cq.securityContext.equals(context)) {
// If there are two different security contexts that both
// have a handle on the same ImageConsumer, then there has
// been a security breach and whether or not they trade
// image data is small fish compared to what they could be
// trading. Throw a Security exception anyway...
errorConsumer(cq, false);
throw new SecurityException("Applets are trading image data!");
}
}
cq.interested = true;
}
if (produce && decoder == null) {
startProduction();
}
}
public synchronized boolean isConsumer(ImageConsumer ic) {
for (ImageDecoder id = decoders; id != null; id = id.next) {
if (id.isConsumer(ic)) {
return true;
}
}
return ImageConsumerQueue.isConsumer(consumers, ic);
}
private void errorAllConsumers(ImageConsumerQueue cq, boolean needReload) {
while (cq != null) {
if (cq.interested) {
errorConsumer(cq, needReload);
}
cq = cq.next;
}
}
private void errorConsumer(ImageConsumerQueue cq, boolean needReload) {
cq.consumer.imageComplete(ImageConsumer.IMAGEERROR);
if ( needReload && cq.consumer instanceof ImageRepresentation) {
((ImageRepresentation)cq.consumer).image.flush();
}
removeConsumer(cq.consumer);
}
public synchronized void removeConsumer(ImageConsumer ic) {
for (ImageDecoder id = decoders; id != null; id = id.next) {
id.removeConsumer(ic);
}
consumers = ImageConsumerQueue.removeConsumer(consumers, ic, false);
}
public void startProduction(ImageConsumer ic) {
addConsumer(ic, true);
}
private synchronized void startProduction() {
if (!awaitingFetch) {
ImageFetcher.add(this);
awaitingFetch = true;
}
}
private synchronized void stopProduction() {
if (awaitingFetch) {
ImageFetcher.remove(this);
awaitingFetch = false;
}
}
public void requestTopDownLeftRightResend(ImageConsumer ic) {
}
protected abstract ImageDecoder getDecoder();
protected ImageDecoder decoderForType(InputStream is,
String content_type) {
// Don't believe the content type - file extensions can
// lie.
/*
if (content_type.equals("image/gif")) {
return new GifImageDecoder(this, is);
} else if (content_type.equals("image/jpeg")) {
return new JPEGImageDecoder(this, is);
} else if (content_type.equals("image/x-xbitmap")) {
return new XbmImageDecoder(this, is);
}
else if (content_type == URL.content_jpeg) {
return new JpegImageDecoder(this, is);
} else if (content_type == URL.content_xbitmap) {
return new XbmImageDecoder(this, is);
} else if (content_type == URL.content_xpixmap) {
return new Xpm2ImageDecoder(this, is);
}
*/
return null;
}
protected ImageDecoder getDecoder(InputStream is) {
if (!is.markSupported())
is = new BufferedInputStream(is);
try {
/* changed to support png
is.mark(6);
*/
is.mark(8);
int c1 = is.read();
int c2 = is.read();
int c3 = is.read();
int c4 = is.read();
int c5 = is.read();
int c6 = is.read();
// added to support png
int c7 = is.read();
int c8 = is.read();
// end of adding
is.reset();
is.mark(-1);
if (c1 == 'G' && c2 == 'I' && c3 == 'F' && c4 == '8') {
return new GifImageDecoder(this, is);
} else if (c1 == '\377' && c2 == '\330' && c3 == '\377') {
return new JPEGImageDecoder(this, is);
} else if (c1 == '#' && c2 == 'd' && c3 == 'e' && c4 == 'f') {
return new XbmImageDecoder(this, is);
// } else if (c1 == '!' && c2 == ' ' && c3 == 'X' && c4 == 'P' &&
// c5 == 'M' && c6 == '2') {
// return new Xpm2ImageDecoder(this, is);
// added to support png
} else if (c1 == 137 && c2 == 80 && c3 == 78 &&
c4 == 71 && c5 == 13 && c6 == 10 &&
c7 == 26 && c8 == 10) {
return new PNGImageDecoder(this, is);
}
// end of adding
} catch (IOException e) {
}
return null;
}
public void doFetch() {
synchronized (this) {
if (consumers == null) {
awaitingFetch = false;
return;
}
}
ImageDecoder imgd = getDecoder();
if (imgd == null) {
badDecoder();
} else {
setDecoder(imgd);
try {
imgd.produceImage();
} catch (IOException e) {
e.printStackTrace();
// the finally clause will send an error.
} catch (ImageFormatException e) {
e.printStackTrace();
// the finally clause will send an error.
} finally {
removeDecoder(imgd);
if ( Thread.currentThread().isInterrupted() || !Thread.currentThread().isAlive()) {
errorAllConsumers(imgd.queue, true);
} else {
errorAllConsumers(imgd.queue, false);
}
}
}
}
private void badDecoder() {
ImageConsumerQueue cq;
synchronized (this) {
cq = consumers;
consumers = null;
awaitingFetch = false;
}
errorAllConsumers(cq, false);
}
private void setDecoder(ImageDecoder mydecoder) {
ImageConsumerQueue cq;
synchronized (this) {
mydecoder.next = decoders;
decoders = mydecoder;
decoder = mydecoder;
cq = consumers;
mydecoder.queue = cq;
consumers = null;
awaitingFetch = false;
}
while (cq != null) {
if (cq.interested) {
// Now that there is a decoder, security may have changed
// so reverify it here, just in case.
if (!checkSecurity(cq.securityContext, true)) {
errorConsumer(cq, false);
}
}
cq = cq.next;
}
}
private synchronized void removeDecoder(ImageDecoder mydecoder) {
doneDecoding(mydecoder);
ImageDecoder idprev = null;
for (ImageDecoder id = decoders; id != null; id = id.next) {
if (id == mydecoder) {
if (idprev == null) {
decoders = id.next;
} else {
idprev.next = id.next;
}
break;
}
idprev = id;
}
}
synchronized void doneDecoding(ImageDecoder mydecoder) {
if (decoder == mydecoder) {
decoder = null;
if (consumers != null) {
startProduction();
}
}
}
void latchConsumers(ImageDecoder id) {
doneDecoding(id);
}
synchronized void flush() {
decoder = null;
}
}