/*
* Copyright 2001 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 ae.com.sun.imageio.plugins.jpeg;
import ae.javax.imageio.metadata.IIOMetadataNode;
import ae.javax.imageio.stream.ImageOutputStream;
import ae.javax.imageio.metadata.IIOInvalidTreeException;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import org.w3c.dom.Node;
/**
* A Comment marker segment. Retains an array of bytes representing the
* comment data as it is read from the stream. If the marker segment is
* constructed from a String, then local default encoding is assumed
* when creating the byte array. If the marker segment is created from
* an <code>IIOMetadataNode</code>, the user object, if present is
* assumed to be a byte array containing the comment data. If there is
* no user object then the comment attribute is used to create the
* byte array, again assuming the default local encoding.
*/
class COMMarkerSegment extends MarkerSegment {
private static final String ENCODING = "ISO-8859-1";
/**
* Constructs a marker segment from the given buffer, which contains
* data from an <code>ImageInputStream</code>. This is used when
* reading metadata from a stream.
*/
COMMarkerSegment(JPEGBuffer buffer) throws IOException {
super(buffer);
loadData(buffer);
}
/**
* Constructs a marker segment from a String. This is used when
* modifying metadata from a non-native tree and when transcoding.
* The default encoding is used to construct the byte array.
*/
COMMarkerSegment(String comment) {
super(JPEG.COM);
data = comment.getBytes(); // Default encoding
}
/**
* Constructs a marker segment from a native tree node. If the node
* is an <code>IIOMetadataNode</code> and contains a user object,
* that object is used rather than the string attribute. If the
* string attribute is used, the default encoding is used.
*/
COMMarkerSegment(Node node) throws IIOInvalidTreeException{
super(JPEG.COM);
if (node instanceof IIOMetadataNode) {
IIOMetadataNode ourNode = (IIOMetadataNode) node;
data = (byte []) ourNode.getUserObject();
}
if (data == null) {
String comment =
node.getAttributes().getNamedItem("comment").getNodeValue();
if (comment != null) {
data = comment.getBytes(); // Default encoding
} else {
throw new IIOInvalidTreeException("Empty comment node!", node);
}
}
}
/**
* Returns the array encoded as a String, using ISO-Latin-1 encoding.
* If an application needs another encoding, the data array must be
* consulted directly.
*/
String getComment() {
try {
return new String (data, ENCODING);
} catch (UnsupportedEncodingException e) {} // Won't happen
return null;
}
/**
* Returns an <code>IIOMetadataNode</code> containing the data array
* as a user object and a string encoded using ISO-8895-1, as an
* attribute.
*/
IIOMetadataNode getNativeNode() {
IIOMetadataNode node = new IIOMetadataNode("com");
node.setAttribute("comment", getComment());
if (data != null) {
node.setUserObject(data.clone());
}
return node;
}
/**
* Writes the data for this segment to the stream in
* valid JPEG format, directly from the data array.
*/
void write(ImageOutputStream ios) throws IOException {
length = 2 + data.length;
writeTag(ios);
ios.write(data);
}
void print() {
printTag("COM");
System.out.println("<" + getComment() + ">");
}
}