001: /*
002: * $RCSfile: PackageUtil.java,v $
003: *
004: *
005: * Copyright (c) 2005 Sun Microsystems, Inc. All Rights Reserved.
006: *
007: * Redistribution and use in source and binary forms, with or without
008: * modification, are permitted provided that the following conditions
009: * are met:
010: *
011: * - Redistribution of source code must retain the above copyright
012: * notice, this list of conditions and the following disclaimer.
013: *
014: * - Redistribution in binary form must reproduce the above copyright
015: * notice, this list of conditions and the following disclaimer in
016: * the documentation and/or other materials provided with the
017: * distribution.
018: *
019: * Neither the name of Sun Microsystems, Inc. or the names of
020: * contributors may be used to endorse or promote products derived
021: * from this software without specific prior written permission.
022: *
023: * This software is provided "AS IS," without a warranty of any
024: * kind. ALL EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND
025: * WARRANTIES, INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY,
026: * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE HEREBY
027: * EXCLUDED. SUN MIDROSYSTEMS, INC. ("SUN") AND ITS LICENSORS SHALL
028: * NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF
029: * USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS
030: * DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR
031: * ANY LOST REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL,
032: * CONSEQUENTIAL, INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND
033: * REGARDLESS OF THE THEORY OF LIABILITY, ARISING OUT OF THE USE OF OR
034: * INABILITY TO USE THIS SOFTWARE, EVEN IF SUN HAS BEEN ADVISED OF THE
035: * POSSIBILITY OF SUCH DAMAGES.
036: *
037: * You acknowledge that this software is not designed or intended for
038: * use in the design, construction, operation or maintenance of any
039: * nuclear facility.
040: *
041: * $Revision: 1.3 $
042: * $Date: 2006/03/31 19:43:38 $
043: * $State: Exp $
044: */
045: package com.sun.media.imageioimpl.common;
046:
047: import java.security.AccessController;
048: import java.security.PrivilegedAction;
049: import com.sun.medialib.codec.jiio.Util;
050:
051: public class PackageUtil {
052: /**
053: * Flag indicating whether codecLib is available.
054: */
055: private static boolean isCodecLibAvailable = false;
056:
057: /**
058: * Implementation version derived from Manifest.
059: */
060: private static String version = "1.0";
061:
062: /**
063: * Implementation vendor derived from Manifest.
064: */
065: private static String vendor = "Sun Microsystems, Inc.";
066:
067: /**
068: * Specification Title derived from Manifest.
069: */
070: private static String specTitle = "Java Advanced Imaging Image I/O Tools";
071:
072: /**
073: * Set static flags.
074: */
075: static {
076: // Set codecLib flag.
077: try {
078: // Check for codecLib availability.
079: isCodecLibAvailable = Util.isCodecLibAvailable();
080: } catch (Throwable e) {
081: // A Throwable is equivalent to unavailable. Throwable is used
082: // in case an Error rather than an Exception is thrown.
083: isCodecLibAvailable = false;
084: }
085:
086: // Set version and vendor strings.
087: try {
088: Class this Class = Class
089: .forName("com.sun.media.imageioimpl.common.PackageUtil");
090: Package this Package = this Class.getPackage();
091: version = this Package.getImplementationVersion();
092: vendor = this Package.getImplementationVendor();
093: specTitle = this Package.getSpecificationTitle();
094: } catch (ClassNotFoundException e) {
095: }
096: }
097:
098: /**
099: * Returns a <code>boolean</code> indicating whether codecLib is available.
100: */
101: public static final boolean isCodecLibAvailable() {
102: // Retrieve value of system property here to allow this to be
103: // modified dynamically.
104: Boolean result = (Boolean) AccessController
105: .doPrivileged(new PrivilegedAction() {
106: public Object run() {
107: String property = null;
108: try {
109: property = System
110: .getProperty("com.sun.media.imageio.disableCodecLib");
111: } catch (SecurityException se) {
112: // Do nothing: leave 'property' null.
113: }
114: return (property != null && property
115: .equalsIgnoreCase("true")) ? Boolean.TRUE
116: : Boolean.FALSE;
117: }
118: });
119: boolean isCodecLibDisabled = result.booleanValue();
120:
121: return isCodecLibAvailable && !isCodecLibDisabled;
122: }
123:
124: /**
125: * Return a version string for the package.
126: */
127: public static final String getVersion() {
128: return version;
129: }
130:
131: /**
132: * Return a vendor string for the package.
133: */
134: public static final String getVendor() {
135: return vendor;
136: }
137:
138: /**
139: * Return the Specification Title string for the package.
140: */
141: public static final String getSpecificationTitle() {
142: return specTitle;
143: }
144: }
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