com.openhtmltopdf.swing.NaiveUserAgent Maven / Gradle / Ivy
/*
* NaiveUserAgent.java
* Copyright (c) 2004, 2005 Torbjoern Gannholm
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public License
* as published by the Free Software Foundation; either version 2.1
* of the License, or (at your option) any later version.
*
* This program 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
*/
package com.openhtmltopdf.swing;
import java.awt.image.BufferedImage;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;
import java.io.UnsupportedEncodingException;
import java.net.MalformedURLException;
import java.net.URI;
import java.net.URISyntaxException;
import java.net.URL;
import java.util.LinkedHashMap;
import java.util.logging.Level;
import javax.imageio.ImageIO;
import com.openhtmltopdf.event.DocumentListener;
import com.openhtmltopdf.extend.FSCache;
import com.openhtmltopdf.extend.FSUriResolver;
import com.openhtmltopdf.extend.HttpStreamFactory;
import com.openhtmltopdf.extend.HttpStream;
import com.openhtmltopdf.extend.UserAgentCallback;
import com.openhtmltopdf.resource.CSSResource;
import com.openhtmltopdf.resource.ImageResource;
import com.openhtmltopdf.resource.XMLResource;
import com.openhtmltopdf.util.ImageUtil;
import com.openhtmltopdf.util.XRLog;
/**
* NaiveUserAgent is a simple implementation of {@link UserAgentCallback} which places no restrictions on what
* XML, CSS or images are loaded, and reports visited links without any filtering. The most straightforward process
* available in the JDK is used to load the resources in question--either using java.io or java.net classes.
*
*
The NaiveUserAgent has a small cache for images,
* the size of which (number of images) can be passed as a constructor argument. There is no automatic cleaning of
* the cache; call {@link #shrinkImageCache()} to remove the least-accessed elements--for example, you might do this
* when a new document is about to be loaded. The NaiveUserAgent is also a DocumentListener; if registered with a
* source of document events (like the panel hierarchy), it will respond to the
* {@link com.openhtmltopdf.event.DocumentListener#documentStarted()} call and attempt to shrink its cache.
*
*
This class is meant as a starting point--it will work out of the box, but you should really implement your
* own, tuned to your application's needs.
*
* @author Torbjoern Gannholm
*/
public class NaiveUserAgent implements UserAgentCallback, DocumentListener {
/**
* a (simple) cache
* This is only useful for the one run. For more than one run, set an external cache with
* setFSCache.
*/
protected final LinkedHashMap _imageCache = new LinkedHashMap();
private final FSUriResolver DEFAULT_URI_RESOLVER = new DefaultUriResolver(this);
protected HttpStreamFactory _streamFactory = new DefaultHttpStreamFactory();
protected FSCache _externalCache = new NullFSCache(false);
protected FSUriResolver _resolver = DEFAULT_URI_RESOLVER;
public static class DefaultHttpStream implements HttpStream {
private InputStream strm;
public DefaultHttpStream(InputStream strm) {
this.strm = strm;
}
@Override
public InputStream getStream() {
return this.strm;
}
@Override
public Reader getReader() {
try {
return new InputStreamReader(this.strm, "UTF-8");
} catch (UnsupportedEncodingException e) {
XRLog.exception("Exception when creating stream reader", e);
}
return null;
}
}
public static class DefaultHttpStreamFactory implements HttpStreamFactory {
@Override
public HttpStream getUrl(String uri) {
InputStream is = null;
try {
is = new URL(uri).openStream();
} catch (java.net.MalformedURLException e) {
XRLog.exception("bad URL given: " + uri, e);
} catch (java.io.FileNotFoundException e) {
XRLog.exception("item at URI " + uri + " not found");
} catch (java.io.IOException e) {
XRLog.exception("IO problem for " + uri, e);
}
return new DefaultHttpStream(is);
}
}
public static class NullFSCache implements FSCache {
private final boolean _log;
public NullFSCache(boolean log) {
this._log = log;
}
@Override
public Object get(FSCacheKey cacheKey) {
if (_log) {
XRLog.load(Level.INFO, "Trying to retrieve object from cache: " + cacheKey.toString());
}
return null;
}
@Override
public void put(FSCacheKey cacheKey, Object obj) {
if (_log) {
XRLog.load(Level.INFO, "Trying to put object in cache: " + cacheKey.toString());
}
}
}
public NaiveUserAgent() {
}
public void setHttpStreamFactory(HttpStreamFactory factory) {
this._streamFactory = factory;
}
public void setExternalCache(FSCache cache) {
this._externalCache = cache;
}
public void setUriResolver(FSUriResolver resolver) {
this._resolver = resolver;
}
public FSUriResolver getDefaultUriResolver() {
return DEFAULT_URI_RESOLVER;
}
/**
* Empties the image cache entirely.
*/
public void clearImageCache() {
_imageCache.clear();
}
/**
* Gets a InputStream for the resource identified by a resolved URI.
*/
protected InputStream openStream(String uri) {
java.io.InputStream is = null;
try {
URL urlObj = new URL(uri);
if (urlObj.getProtocol().equalsIgnoreCase("http") ||
urlObj.getProtocol().equalsIgnoreCase("https")) {
return _streamFactory.getUrl(uri).getStream();
}
else {
try {
is = new URL(uri).openStream();
} catch (java.net.MalformedURLException e) {
XRLog.exception("bad URL given: " + uri, e);
} catch (java.io.FileNotFoundException e) {
XRLog.exception("item at URI " + uri + " not found");
} catch (java.io.IOException e) {
XRLog.exception("IO problem for " + uri, e);
}
}
} catch (MalformedURLException e2) {
XRLog.exception("bad URL given: " + uri, e2);
}
return is;
}
/**
* Gets a reader for the identified resource by a resolved URI.
*/
protected Reader openReader(String uri) {
InputStream is = null;
try {
URL urlObj = new URL(uri);
if (urlObj.getProtocol().equalsIgnoreCase("http") ||
urlObj.getProtocol().equalsIgnoreCase("https")) {
return _streamFactory.getUrl(uri).getReader();
}
else {
try {
is = new URL(uri).openStream();
} catch (java.net.MalformedURLException e) {
XRLog.exception("bad URL given: " + uri, e);
} catch (java.io.FileNotFoundException e) {
XRLog.exception("item at URI " + uri + " not found");
} catch (java.io.IOException e) {
XRLog.exception("IO problem for " + uri, e);
}
}
} catch (MalformedURLException e2) {
XRLog.exception("bad URL given: " + uri, e2);
}
try {
return is == null ? null : new InputStreamReader(is, "UTF-8");
} catch (UnsupportedEncodingException e) {
XRLog.exception("Failed to create stream reader", e);
}
return null;
}
/**
* Retrieves the CSS located at the given URI. It's assumed the URI does point to a CSS file--the URI will
* be accessed (using the set HttpStreamFactory or URL::openStream), opened, read and then passed into the CSS parser.
* The result is packed up into an CSSResource for later consumption.
*
* @param uri Location of the CSS source.
* @return A CSSResource containing the parsed CSS.
*/
@Override
public CSSResource getCSSResource(String uri) {
String resolved = _resolver.resolveURI(uri);
FSCacheKey cacheKey = new FSCacheKey(resolved, CSSResource.class);
CSSResource res = (CSSResource) _externalCache.get(cacheKey);
if (res != null) {
return res;
}
CSSResource res2 = new CSSResource(openReader(resolved));
_externalCache.put(cacheKey, res2);
return res2;
}
/**
* Retrieves the image located at the given URI. It's assumed the URI does point to an image--the URI will
* be accessed (using the set HttpStreamFactory or URL::openStream), opened, read and then passed into the JDK image-parsing routines.
* The result is packed up into an ImageResource for later consumption.
*
* @param uri Location of the image source.
* @return An ImageResource containing the image.
*/
@Override
public ImageResource getImageResource(String uri) {
System.out.println("Getting image: " + uri);
ImageResource ir;
if (ImageUtil.isEmbeddedBase64Image(uri)) {
BufferedImage image = ImageUtil.loadEmbeddedBase64Image(uri);
return new ImageResource(null, AWTFSImage.createImage(image));
} else {
String resolved = _resolver.resolveURI(uri);
// First, we check the internal per run cache.
ir = _imageCache.get(resolved);
if (ir != null) {
return ir;
}
// Then check the external multi run cache.
AWTFSImage fsImage = (AWTFSImage) _externalCache.get(new FSCacheKey(resolved, AWTFSImage.class));
if (fsImage != null) {
return new ImageResource(resolved, fsImage);
}
// Finally we fetch from the network or file, etc.
InputStream is = openStream(resolved);
if (is != null) {
try {
BufferedImage img = ImageIO.read(is);
if (img == null) {
throw new IOException("ImageIO.read() returned null");
}
AWTFSImage fsImage2 = (AWTFSImage) AWTFSImage.createImage(img);
_externalCache.put(new FSCacheKey(resolved, AWTFSImage.class), fsImage2);
ir = new ImageResource(resolved, fsImage2);
_imageCache.put(resolved, ir);
return ir;
} catch (FileNotFoundException e) {
XRLog.exception("Can't read image file; image at URI '" + resolved + "' not found");
} catch (IOException e) {
XRLog.exception("Can't read image file; unexpected problem for URI '" + resolved + "'", e);
} finally {
try {
is.close();
} catch (IOException e) {
// ignore
}
}
}
return new ImageResource(resolved, null);
}
}
/**
* Retrieves the XML located at the given URI. It's assumed the URI does point to a XML--the URI will
* be accessed (using the set HttpStreamFactory or URL::openStream), opened, read and then passed into the XML parser (XMLReader)
* configured for Flying Saucer. The result is packed up into an XMLResource for later consumption.
*
* @param uri Location of the XML source.
* @return An XMLResource containing the image.
*/
@Override
public XMLResource getXMLResource(String uri) {
String resolved = _resolver.resolveURI(uri);
XMLResource res = (XMLResource) _externalCache.get(new FSCacheKey(resolved, XMLResource.class));
if (res != null) {
return res;
}
Reader inputReader = openReader(resolved);
XMLResource xmlResource;
try {
xmlResource = XMLResource.load(inputReader);
} finally {
if (inputReader != null) {
try {
inputReader.close();
} catch (IOException e) {
// swallow
}
}
}
_externalCache.put(new FSCacheKey(resolved, XMLResource.class), xmlResource);
return xmlResource;
}
@Override
public byte[] getBinaryResource(String uri) {
String resolved = _resolver.resolveURI(uri);
byte[] bytes = (byte[]) _externalCache.get(new FSCacheKey(resolved, byte[].class));
if (bytes != null) {
return bytes;
}
InputStream is = openStream(resolved);
if (is == null) {
return null;
}
try {
ByteArrayOutputStream result = new ByteArrayOutputStream();
byte[] buf = new byte[10240];
int i;
while ((i = is.read(buf)) != -1) {
result.write(buf, 0, i);
}
is.close();
is = null;
byte[] bytes2 = result.toByteArray();
_externalCache.put(new FSCacheKey(resolved, byte[].class), bytes2);
return bytes2;
} catch (IOException e) {
return null;
} finally {
if (is != null) {
try {
is.close();
} catch (IOException e) {
// ignore
}
}
}
}
/**
* Returns true if the given URI was visited, meaning it was requested at some point since initialization.
*
* @param uri A URI which might have been visited.
* @return Always false; visits are not tracked in the NaiveUserAgent.
*/
@Override
public boolean isVisited(String uri) {
return false;
}
/**
* URL relative to which URIs are resolved.
*
* @param url A URI which anchors other, possibly relative URIs.
*/
@Override
public void setBaseURL(String url) {
_resolver.setBaseURL(url);
}
public static class DefaultUriResolver implements FSUriResolver {
private final NaiveUserAgent _agent;
private String _baseURI;
private DefaultUriResolver(NaiveUserAgent agent) {
this._agent = agent;
}
/**
* Resolves the URI; if absolute, leaves as is, if relative, returns an
* absolute URI based on the baseUrl for the agent.
*
* @param uri
* A URI, possibly relative.
*
* @return A URI as String, resolved, or null if there was an exception
* (for example if the URI is malformed).
*/
@Override
public String resolveURI(String uri) {
if (uri == null)
return null;
String ret = null;
if (_agent.getBaseURL() == null) {// first try to set a base URL
try {
URI result = new URI(uri);
if (result.isAbsolute())
_agent.setBaseURL(result.toString());
} catch (URISyntaxException e) {
XRLog.exception(
"The default NaiveUserAgent could not use the URL as base url: " + uri, e);
}
if (_agent.getBaseURL() == null) { // still not set -> fallback to current working directory
try {
XRLog.load(Level.WARNING, "Using current working directiory as base uri.");
_agent.setBaseURL(new File(".").toURI().toURL().toExternalForm());
} catch (Exception e1) {
XRLog.exception("The default NaiveUserAgent doesn't know how to resolve the base URL for " + uri);
return null;
}
}
}
// test if the URI is valid; if not, try to assign the base url as
// its parent
try {
URI result = new URI(uri);
if (!result.isAbsolute()) {
XRLog.load(uri
+ " is not a URL; may be relative. Testing using parent URL "
+ _agent.getBaseURL());
result = new URI(_agent.getBaseURL()).resolve(result);
}
ret = result.toString();
} catch (URISyntaxException e) {
XRLog.exception("The default NaiveUserAgent cannot resolve the URL "
+ uri + " with base URL " + _agent.getBaseURL());
}
return ret;
}
@Override
public void setBaseURL(String uri) {
this._baseURI = uri;
}
@Override
public String getBaseURL() {
return this._baseURI;
}
}
/**
* Returns the current baseUrl for this class.
*/
@Override
public String getBaseURL() {
return _resolver.getBaseURL();
}
@Override
public void documentStarted() {
clearImageCache();
}
@Override
public void documentLoaded() { /* ignore*/ }
@Override
public void onLayoutException(Throwable t) { /* ignore*/ }
@Override
public void onRenderException(Throwable t) { /* ignore*/ }
@Override
public String resolveURI(String uri) {
return _resolver.resolveURI(uri);
}
}
/*
* $Id$
*
* $Log$
* Revision 1.40 2009/05/15 16:20:10 pdoubleya
* ImageResource now tracks the URI for the image that was created and handles mutable images.
*
* Revision 1.39 2009/04/12 11:16:51 pdoubleya
* Remove proposed patch for URLs that are incorrectly handled on Windows; need a more reliable solution.
*
* Revision 1.38 2008/04/30 23:14:18 peterbrant
* Do a better job of cleaning up open file streams (patch by Christophe Marchand)
*
* Revision 1.37 2007/11/23 07:03:30 pdoubleya
* Applied patch from N. Barozzi to allow either toolkit or buffered images to be used, see https://xhtmlrenderer.dev.java.net/servlets/ReadMsg?list=dev&msgNo=3847
*
* Revision 1.36 2007/10/31 23:14:43 peterbrant
* Add rudimentary support for @font-face rules
*
* Revision 1.35 2007/06/20 12:24:31 pdoubleya
* Fix bug in shrink cache, trying to modify iterator without using safe remove().
*
* Revision 1.34 2007/06/19 21:25:41 pdoubleya
* Cleanup for caching in NUA, making it more suitable to use as a reusable UAC. NUA is also now a document listener and uses this to try and trim its cache down. PanelManager and iTextUA are now NUA subclasses.
*
* Revision 1.33 2007/05/20 23:25:33 peterbrant
* Various code cleanups (e.g. remove unused imports)
*
* Patch from Sean Bright
*
* Revision 1.32 2007/05/09 21:52:06 pdoubleya
* Fix for rendering problems introduced by removing GraphicsUtil class. Use Image instead of BufferedImage in most cases, convert to AWT image if necessary. Not complete, requires cleanup.
*
* Revision 1.31 2007/05/05 21:08:27 pdoubleya
* Changed image-related interfaces (FSImage, ImageUtil, scaling) to all use BufferedImage, since there were no Image-specific APIs we depended on, and we have more control over what we do with BIs as compared to Is.
*
* Revision 1.30 2007/05/05 18:05:21 pdoubleya
* Remove references to GraphicsUtil and the class itself, no longer needed
*
* Revision 1.29 2007/04/10 20:46:02 pdoubleya
* Fix, was not closing XML source stream when done
*
* Revision 1.28 2007/02/07 16:33:31 peterbrant
* Initial commit of rewritten table support and associated refactorings
*
* Revision 1.27 2006/06/28 13:46:59 peterbrant
* ImageIO.read() can apparently return sometimes null instead of throwing an exception when processing an invalid image
*
* Revision 1.26 2006/04/27 13:28:48 tobega
* Handle situations without base url and no file access gracefully
*
* Revision 1.25 2006/04/25 00:23:20 peterbrant
* Fixes from Mike Curtis
*
* Revision 1.23 2006/04/08 08:21:24 tobega
* relative urls and linked stylesheets
*
* Revision 1.22 2006/02/02 02:47:33 peterbrant
* Support non-AWT images
*
* Revision 1.21 2005/10/25 19:40:38 tobega
* Suggestion from user to use File.toURI.toURL instead of File.toURL because the latter is buggy
*
* Revision 1.20 2005/10/09 09:40:27 tobega
* Use current directory as default base URL
*
* Revision 1.19 2005/08/11 01:35:37 joshy
* removed debugging
* updated stylesheet to use right aligns
* Issue number:
* Obtained from:
* Submitted by:
* Reviewed by:
*
* Revision 1.17 2005/06/25 19:27:47 tobega
* UAC now supplies Resources
*
* Revision 1.16 2005/06/25 17:23:35 tobega
* first refactoring of UAC: ImageResource
*
* Revision 1.15 2005/06/21 17:52:10 joshy
* new hover code
* removed some debug statements
* Issue number:
* Obtained from:
* Submitted by:
* Reviewed by:
*
* Revision 1.14 2005/06/20 23:45:56 joshy
* hack to fix the mangled background images on osx
* Issue number:
* Obtained from:
* Submitted by:
* Reviewed by:
*
* Revision 1.13 2005/06/20 17:26:45 joshy
* debugging for image issues
* font scale stuff
*
* Issue number:
* Obtained from:
* Submitted by:
* Reviewed by:
*
* Revision 1.12 2005/06/15 11:57:18 tobega
* Making Browser a better model application with UserAgentCallback
*
* Revision 1.11 2005/06/15 11:53:47 tobega
* Changed UserAgentCallback to getInputStream instead of getReader. Fixed up some consequences of previous change.
*
* Revision 1.10 2005/06/13 06:50:16 tobega
* Fixed a bug in table content resolution.
* Various "tweaks" in other stuff.
*
* Revision 1.9 2005/06/03 00:29:49 tobega
* fixed potential bug
*
* Revision 1.8 2005/06/01 21:36:44 tobega
* Got image scaling working, and did some refactoring along the way
*
* Revision 1.7 2005/03/28 14:24:22 pdoubleya
* Remove stack trace on loading images.
*
* Revision 1.6 2005/02/02 12:14:01 pdoubleya
* Clean, format, buffer reader.
*
*
*/