/*
============================================================================
The Apache Software License, Version 1.1
============================================================================
Copyright (C) 1999-2002 The Apache Software Foundation. All rights reserved.
Redistribution and use in source and binary forms, with or without modifica-
tion, are permitted provided that the following conditions are met:
1. Redistributions of source code must retain the above copyright notice,
this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright notice,
this list of conditions and the following disclaimer in the documentation
and/or other materials provided with the distribution.
3. The end-user documentation included with the redistribution, if any, must
include the following acknowledgment: "This product includes software
developed by the Apache Software Foundation (http://www.apache.org/)."
Alternately, this acknowledgment may appear in the software itself, if
and wherever such third-party acknowledgments normally appear.
4. The names "Apache Cocoon" and "Apache Software Foundation" must not be
used to endorse or promote products derived from this software without
prior written permission. For written permission, please contact
apache@apache.org.
5. Products derived from this software may not be called "Apache", nor may
"Apache" appear in their name, without prior written permission of the
Apache Software Foundation.
THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
APACHE SOFTWARE FOUNDATION OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLU-
DING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
This software consists of voluntary contributions made by many individuals
on behalf of the Apache Software Foundation and was originally created by
Stefano Mazzocchi <stefano@apache.org>. For more information on the Apache
Software Foundation, please see <http://www.apache.org/>.
*/
package org.apache.cocoon.reading;
import org.apache.avalon.framework.component.ComponentManager;
import org.apache.avalon.framework.component.Composable;
import org.apache.avalon.framework.parameters.Parameters;
import org.apache.cocoon.ProcessingException;
import org.apache.cocoon.caching.CacheValidity;
import org.apache.cocoon.caching.Cacheable;
import org.apache.cocoon.caching.TimeStampCacheValidity;
import org.apache.cocoon.environment.Context;
import org.apache.cocoon.environment.ObjectModelHelper;
import org.apache.cocoon.environment.Request;
import org.apache.cocoon.environment.Response;
import org.apache.cocoon.environment.Source;
import org.apache.cocoon.environment.SourceResolver;
import org.apache.cocoon.util.HashUtil;
import com.sun.image.codec.jpeg.ImageFormatException;
import com.sun.image.codec.jpeg.JPEGCodec;
import com.sun.image.codec.jpeg.JPEGDecodeParam;
import com.sun.image.codec.jpeg.JPEGImageDecoder;
import com.sun.image.codec.jpeg.JPEGImageEncoder;
import org.xml.sax.SAXException;
import java.awt.geom.AffineTransform;
import java.awt.image.AffineTransformOp;
import java.awt.image.Raster;
import java.awt.image.WritableRaster;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Date;
import java.util.Map;
/**
* The <code>ImageReader</code> component is used to serve binary image data
* in a sitemap pipeline. It makes use of HTTP Headers to determine if
* the requested resource should be written to the <code>OutputStream</code>
* or if it can signal that it hasn't changed.
*
* Parameters:
* <dl>
* <dt><width></dt>
* <dd>This parameter is optional. When specified it determines the width
* of the image that should be served.
* </dd>
* <dt><height></dt>
* <dd>This parameter is optional. When specified it determines the height
* of the image that should be served.
* </dd>
* </dl>
*
* @author <a href="mailto:stefano@apache.org">Stefano Mazzocchi</a>
* @version CVS $Revision: 1.3.2.1 $ $Date: 2002/06/11 23:54:53 $
*/
public class ImageReader extends AbstractReader implements Composable, Cacheable {
private ComponentManager manager;
public void compose(ComponentManager manager) {
this.manager = manager;
}
private Source inputSource;
private Response response;
private Request request;
private int width;
private int height;
private int expireTime;
private String format;
public void setup(SourceResolver resolver, Map objectModel, String src, Parameters par)
throws ProcessingException, SAXException, IOException {
super.setup(resolver, objectModel, src, par);
this.request = ObjectModelHelper.getRequest(objectModel);
this.response = ObjectModelHelper.getResponse(objectModel);
this.width = par.getParameterAsInteger("width", 0);
this.height = par.getParameterAsInteger("height", 0);
this.expireTime = par.getParameterAsInteger("expire-time", -1);
getLogger().debug("Image data: [" + this.width + "x" + this.height + "] Expire Time: " + expireTime);
this.inputSource = this.resolver.resolve(super.source);
}
/**
* Generate the unique key.
* This key must be unique inside the space of this component.
*
* @return The generated key hashes the src
*/
public long generateKey() {
return HashUtil.hash(this.inputSource.getSystemId() + ":" + width + height);
}
/**
* Generate the validity object.
*
* @return The generated validity object or <code>null</code> if the
* component is currently not cacheable.
*/
public CacheValidity generateValidity() {
return new TimeStampCacheValidity(this.inputSource.getLastModified());
}
/**
* @return the time the read source was last modified or 0 if it is not
* possible to detect
*/
public long getLastModified() {
return this.inputSource.getLastModified();
}
/**
* Generates the requested resource.
*/
public void generate() throws IOException, ProcessingException {
if (expireTime > 0) {
response.setDateHeader("Expires", new Date().getTime() + expireTime);
}
InputStream in = this.inputSource.getInputStream();
if ((width == 0) && (height == 0)) {
read(in, out);
} else {
convert(in, width, height, out);
}
}
private void read(InputStream in, OutputStream out) {
try {
response.setHeader("Accept-Ranges", "bytes");
byte[] buffer = new byte[8192];
int length = -1;
while ((length = in.read(buffer)) > -1) {
out.write(buffer, 0, length);
}
in.close();
out.flush();
} catch (IOException ioe) {
getLogger().debug("Received an IOException, assuming client severed connection on purpose");
}
}
/**
* Returns the affine transform that implements the scaling.
* The behavior is the following: if both the new width and height values
* are positive, the image is rescaled according to these new values and
* the original aspect ration is lost.
* Otherwise, if one of the two parameters is zero or negative, the
* aspect ratio is maintained and the positive parameter indicates the
* scaling.
* If both new values are zero or negative, no scaling takes place (a unit
* transformation is applied).
*/
private AffineTransform getTransform(double ow, double oh, double nw, double nh) {
double wm = 1.0d;
double hm = 1.0d;
if (nw > 0) {
wm = nw / ow;
if (nh > 0) {
hm = nh / oh;
} else {
hm = wm;
}
} else {
if (nh > 0) {
hm = nh / oh;
wm = hm;
}
}
return new AffineTransform(wm, 0.0d, 0.0d, hm, 0.0d, 0.0d);
}
/**
* NOTE (SM):
* Due to Bug Id 4502892 (which is found in *all* JVM implementations from
* 1.2.x and 1.3.x on all OS!), we must buffer the JPEG generation to avoid
* that connection resetting by the peer (user pressing the stop button,
* for example) crashes the entire JVM (yes, dude, the bug is *that* nasty
* since it happens in JPEG routines which are native!)
* I'm perfectly aware of the huge memory problems that this causes (almost
* doubling memory consuption for each image and making the GC work twice
* as hard) but it's *far* better than restarting the JVM every 2 minutes
* (since this is the average experience for image-intensive web application
* such as an image gallery).
* Please, go to the <a href="http://developer.java.sun.com/developer/bugParade/bugs/4502892.html">Sun Developers Connection</a>
* and vote this BUG as the one you would like fixed sooner rather than
* later and all this hack will automagically go away.
* Many deep thanks to Michael Hartle <mhartle@hartle-klug.com> for tracking
* this down and suggesting the workaround.
*
* UPDATE (SM):
* This appears to be fixed on JDK 1.4
*/
private void convert(InputStream in, double w, double h, OutputStream out) throws IOException, ProcessingException {
try {
JPEGImageDecoder decoder = JPEGCodec.createJPEGDecoder(in);
Raster original = decoder.decodeAsRaster();
JPEGDecodeParam decodeParam = decoder.getJPEGDecodeParam();
double ow = (double) decodeParam.getWidth();
double oh = (double) decodeParam.getHeight();
AffineTransformOp filter = new AffineTransformOp(getTransform(ow, oh, w, h), AffineTransformOp.TYPE_BILINEAR);
WritableRaster scaled = filter.createCompatibleDestRaster(original);
filter.filter(original, scaled);
// JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);
ByteArrayOutputStream bstream = new ByteArrayOutputStream();
JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(bstream);
encoder.encode(scaled);
in.close();
out.write(bstream.toByteArray());
out.flush();
} catch (ImageFormatException e) {
throw new ProcessingException("Error reading the image. Note that only JPEG images are currently supported.");
}
}
/**
* Returns the mime-type of the resource in process.
*/
public String getMimeType() {
Context ctx = ObjectModelHelper.getContext(objectModel);
return (ctx != null) ? ctx.getMimeType(this.source) : null;
}
}