alvinalexander.com | career | drupal | java | mac | mysql | perl | scala | uml | unix  

Java example source code file (GIFWritableImageMetadata.java)

This example Java source code file (GIFWritableImageMetadata.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

applicationextension, applicationextensions, arraylist, bad, commentextensions, dom, gifwritableimagemetadata, iioinvalidtreeexception, image, imageio, iso\-8859\-1, localcolortable, native_format_name, node, only, root, string, util

The GIFWritableImageMetadata.java Java example source code

/*
 * Copyright (c) 2005, 2008, Oracle and/or its affiliates. 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.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package com.sun.imageio.plugins.gif;

import java.io.UnsupportedEncodingException;
import java.nio.charset.Charset;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import javax.imageio.ImageTypeSpecifier;
import javax.imageio.metadata.IIOInvalidTreeException;
import javax.imageio.metadata.IIOMetadata;
import javax.imageio.metadata.IIOMetadataNode;
import javax.imageio.metadata.IIOMetadataFormat;
import javax.imageio.metadata.IIOMetadataFormatImpl;
import org.w3c.dom.Node;

class GIFWritableImageMetadata extends GIFImageMetadata {

    // package scope
    static final String
    NATIVE_FORMAT_NAME = "javax_imageio_gif_image_1.0";

    GIFWritableImageMetadata() {
        super(true,
              NATIVE_FORMAT_NAME,
              "com.sun.imageio.plugins.gif.GIFImageMetadataFormat",
              null, null);
    }

    public boolean isReadOnly() {
        return false;
    }

    public void reset() {
        // Fields from Image Descriptor
        imageLeftPosition = 0;
        imageTopPosition = 0;
        imageWidth = 0;
        imageHeight = 0;
        interlaceFlag = false;
        sortFlag = false;
        localColorTable = null;

        // Fields from Graphic Control Extension
        disposalMethod = 0;
        userInputFlag = false;
        transparentColorFlag = false;
        delayTime = 0;
        transparentColorIndex = 0;

        // Fields from Plain Text Extension
        hasPlainTextExtension = false;
        textGridLeft = 0;
        textGridTop = 0;
        textGridWidth = 0;
        textGridHeight = 0;
        characterCellWidth = 0;
        characterCellHeight = 0;
        textForegroundColor = 0;
        textBackgroundColor = 0;
        text = null;

        // Fields from ApplicationExtension
        applicationIDs = null;
        authenticationCodes = null;
        applicationData = null;

        // Fields from CommentExtension
        // List of byte[]
        comments = null;
    }

    private byte[] fromISO8859(String data) {
        try {
            return data.getBytes("ISO-8859-1");
        } catch (UnsupportedEncodingException e) {
            return "".getBytes();
        }
    }

    protected void mergeNativeTree(Node root) throws IIOInvalidTreeException {
        Node node = root;
        if (!node.getNodeName().equals(nativeMetadataFormatName)) {
            fatal(node, "Root must be " + nativeMetadataFormatName);
        }

        node = node.getFirstChild();
        while (node != null) {
            String name = node.getNodeName();

            if (name.equals("ImageDescriptor")) {
                imageLeftPosition = getIntAttribute(node,
                                                    "imageLeftPosition",
                                                    -1, true,
                                                    true, 0, 65535);

                imageTopPosition = getIntAttribute(node,
                                                   "imageTopPosition",
                                                   -1, true,
                                                   true, 0, 65535);

                imageWidth = getIntAttribute(node,
                                             "imageWidth",
                                             -1, true,
                                             true, 1, 65535);

                imageHeight = getIntAttribute(node,
                                              "imageHeight",
                                              -1, true,
                                              true, 1, 65535);

                interlaceFlag = getBooleanAttribute(node, "interlaceFlag",
                                                    false, true);
            } else if (name.equals("LocalColorTable")) {
                int sizeOfLocalColorTable =
                    getIntAttribute(node, "sizeOfLocalColorTable",
                                    true, 2, 256);
                if (sizeOfLocalColorTable != 2 &&
                    sizeOfLocalColorTable != 4 &&
                    sizeOfLocalColorTable != 8 &&
                    sizeOfLocalColorTable != 16 &&
                    sizeOfLocalColorTable != 32 &&
                    sizeOfLocalColorTable != 64 &&
                    sizeOfLocalColorTable != 128 &&
                    sizeOfLocalColorTable != 256) {
                    fatal(node,
                          "Bad value for LocalColorTable attribute sizeOfLocalColorTable!");
                }

                sortFlag = getBooleanAttribute(node, "sortFlag", false, true);

                localColorTable = getColorTable(node, "ColorTableEntry",
                                                true, sizeOfLocalColorTable);
            } else if (name.equals("GraphicControlExtension")) {
                String disposalMethodName =
                    getStringAttribute(node, "disposalMethod", null,
                                       true, disposalMethodNames);
                disposalMethod = 0;
                while(!disposalMethodName.equals(disposalMethodNames[disposalMethod])) {
                    disposalMethod++;
                }

                userInputFlag = getBooleanAttribute(node, "userInputFlag",
                                                    false, true);

                transparentColorFlag =
                    getBooleanAttribute(node, "transparentColorFlag",
                                        false, true);

                delayTime = getIntAttribute(node,
                                            "delayTime",
                                            -1, true,
                                            true, 0, 65535);

                transparentColorIndex =
                    getIntAttribute(node, "transparentColorIndex",
                                    -1, true,
                                    true, 0, 65535);
            } else if (name.equals("PlainTextExtension")) {
                hasPlainTextExtension = true;

                textGridLeft = getIntAttribute(node,
                                               "textGridLeft",
                                               -1, true,
                                               true, 0, 65535);

                textGridTop = getIntAttribute(node,
                                              "textGridTop",
                                              -1, true,
                                              true, 0, 65535);

                textGridWidth = getIntAttribute(node,
                                                "textGridWidth",
                                                -1, true,
                                                true, 1, 65535);

                textGridHeight = getIntAttribute(node,
                                                 "textGridHeight",
                                                 -1, true,
                                                 true, 1, 65535);

                characterCellWidth = getIntAttribute(node,
                                                     "characterCellWidth",
                                                     -1, true,
                                                     true, 1, 65535);

                characterCellHeight = getIntAttribute(node,
                                                      "characterCellHeight",
                                                      -1, true,
                                                      true, 1, 65535);

                textForegroundColor = getIntAttribute(node,
                                                      "textForegroundColor",
                                                      -1, true,
                                                      true, 0, 255);

                textBackgroundColor = getIntAttribute(node,
                                                      "textBackgroundColor",
                                                      -1, true,
                                                      true, 0, 255);

                // XXX The "text" attribute of the PlainTextExtension element
                // is not defined in the GIF image metadata format but it is
                // present in the GIFImageMetadata class. Consequently it is
                // used here but not required and with a default of "". See
                // bug 5082763.

                String textString =
                    getStringAttribute(node, "text", "", false, null);
                text = fromISO8859(textString);
            } else if (name.equals("ApplicationExtensions")) {
                IIOMetadataNode applicationExtension =
                    (IIOMetadataNode)node.getFirstChild();

                if (!applicationExtension.getNodeName().equals("ApplicationExtension")) {
                    fatal(node,
                          "Only a ApplicationExtension may be a child of a ApplicationExtensions!");
                }

                String applicationIDString =
                    getStringAttribute(applicationExtension, "applicationID",
                                       null, true, null);

                String authenticationCodeString =
                    getStringAttribute(applicationExtension, "authenticationCode",
                                       null, true, null);

                Object applicationExtensionData =
                    applicationExtension.getUserObject();
                if (applicationExtensionData == null ||
                    !(applicationExtensionData instanceof byte[])) {
                    fatal(applicationExtension,
                          "Bad user object in ApplicationExtension!");
                }

                if (applicationIDs == null) {
                    applicationIDs = new ArrayList();
                    authenticationCodes = new ArrayList();
                    applicationData = new ArrayList();
                }

                applicationIDs.add(fromISO8859(applicationIDString));
                authenticationCodes.add(fromISO8859(authenticationCodeString));
                applicationData.add(applicationExtensionData);
            } else if (name.equals("CommentExtensions")) {
                Node commentExtension = node.getFirstChild();
                if (commentExtension != null) {
                    while(commentExtension != null) {
                        if (!commentExtension.getNodeName().equals("CommentExtension")) {
                            fatal(node,
                                  "Only a CommentExtension may be a child of a CommentExtensions!");
                        }

                        if (comments == null) {
                            comments = new ArrayList();
                        }

                        String comment =
                            getStringAttribute(commentExtension, "value", null,
                                               true, null);

                        comments.add(fromISO8859(comment));

                        commentExtension = commentExtension.getNextSibling();
                    }
                }
            } else {
                fatal(node, "Unknown child of root node!");
            }

            node = node.getNextSibling();
        }
    }

    protected void mergeStandardTree(Node root)
      throws IIOInvalidTreeException {
        Node node = root;
        if (!node.getNodeName()
            .equals(IIOMetadataFormatImpl.standardMetadataFormatName)) {
            fatal(node, "Root must be " +
                  IIOMetadataFormatImpl.standardMetadataFormatName);
        }

        node = node.getFirstChild();
        while (node != null) {
            String name = node.getNodeName();

            if (name.equals("Chroma")) {
                Node childNode = node.getFirstChild();
                while(childNode != null) {
                    String childName = childNode.getNodeName();
                    if (childName.equals("Palette")) {
                        localColorTable = getColorTable(childNode,
                                                        "PaletteEntry",
                                                        false, -1);
                        break;
                    }
                    childNode = childNode.getNextSibling();
                }
            } else if (name.equals("Compression")) {
                Node childNode = node.getFirstChild();
                while(childNode != null) {
                    String childName = childNode.getNodeName();
                    if (childName.equals("NumProgressiveScans")) {
                        int numProgressiveScans =
                            getIntAttribute(childNode, "value", 4, false,
                                            true, 1, Integer.MAX_VALUE);
                        if (numProgressiveScans > 1) {
                            interlaceFlag = true;
                        }
                        break;
                    }
                    childNode = childNode.getNextSibling();
                }
            } else if (name.equals("Dimension")) {
                Node childNode = node.getFirstChild();
                while(childNode != null) {
                    String childName = childNode.getNodeName();
                    if (childName.equals("HorizontalPixelOffset")) {
                        imageLeftPosition = getIntAttribute(childNode,
                                                            "value",
                                                            -1, true,
                                                            true, 0, 65535);
                    } else if (childName.equals("VerticalPixelOffset")) {
                        imageTopPosition = getIntAttribute(childNode,
                                                           "value",
                                                           -1, true,
                                                           true, 0, 65535);
                    }
                    childNode = childNode.getNextSibling();
                }
            } else if (name.equals("Text")) {
                Node childNode = node.getFirstChild();
                while(childNode != null) {
                    String childName = childNode.getNodeName();
                    if (childName.equals("TextEntry") &&
                        getAttribute(childNode, "compression",
                                     "none", false).equals("none") &&
                        Charset.isSupported(getAttribute(childNode,
                                                         "encoding",
                                                         "ISO-8859-1",
                                                         false))) {
                        String value = getAttribute(childNode, "value");
                        byte[] comment = fromISO8859(value);
                        if (comments == null) {
                            comments = new ArrayList();
                        }
                        comments.add(comment);
                    }
                    childNode = childNode.getNextSibling();
                }
            } else if (name.equals("Transparency")) {
                Node childNode = node.getFirstChild();
                while(childNode != null) {
                    String childName = childNode.getNodeName();
                    if (childName.equals("TransparentIndex")) {
                        transparentColorIndex = getIntAttribute(childNode,
                                                                "value",
                                                                -1, true,
                                                                true, 0, 255);
                        transparentColorFlag = true;
                        break;
                    }
                    childNode = childNode.getNextSibling();
                }
            }

            node = node.getNextSibling();
        }
    }

    public void setFromTree(String formatName, Node root)
        throws IIOInvalidTreeException
    {
        reset();
        mergeTree(formatName, root);
    }
}

Other Java examples (source code examples)

Here is a short list of links related to this Java GIFWritableImageMetadata.java source code file:

... this post is sponsored by my books ...

#1 New Release!

FP Best Seller

 

new blog posts

 

Copyright 1998-2021 Alvin Alexander, alvinalexander.com
All Rights Reserved.

A percentage of advertising revenue from
pages under the /java/jwarehouse URI on this website is
paid back to open source projects.