bundles/org.eclipse.equinox.p2.repository.tools/src/org/eclipse/equinox/p2/internal/repository/comparator/JarComparator.java - equinox/rt.equinox.p2 - Git at Google

 /*******************************************************************************
  * Copyright (c) 2009, 2012 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  *     IBM Corporation - initial API and implementation
  *******************************************************************************/
 package org.eclipse.equinox.p2.internal.repository.comparator;

 import java.io.*;
 import java.util.*;
 import java.util.Map.Entry;
 import java.util.jar.*;
 import java.util.zip.ZipEntry;
 import java.util.zip.ZipFile;
 import org.eclipse.core.runtime.*;
 import org.eclipse.equinox.internal.p2.publisher.eclipse.FeatureParser;
 import org.eclipse.equinox.p2.internal.repository.comparator.java.*;
 import org.eclipse.equinox.p2.publisher.eclipse.Feature;
 import org.eclipse.equinox.p2.publisher.eclipse.FeatureEntry;
 import org.eclipse.equinox.p2.repository.artifact.IArtifactDescriptor;
 import org.eclipse.equinox.p2.repository.artifact.IArtifactRepository;
 import org.eclipse.equinox.p2.repository.tools.comparator.IArtifactComparator;
 import org.eclipse.osgi.util.NLS;

 /**
  * An artifact comparator that compares two JAR files. Class files are disassembled
  * and compared for equivalence, properties and manifest files are compared as such,
  * all other files are compared byte-for-byte.
  */
 public class JarComparator implements IArtifactComparator {

 	private static class FeatureEntryWrapper {
 		private FeatureEntry entry;

 		public FeatureEntryWrapper(FeatureEntry entry) {
 			this.entry = entry;
 		}

 		@Override
 		public boolean equals(Object o) {
 			FeatureEntry otherEntry = (o instanceof FeatureEntryWrapper) ? ((FeatureEntryWrapper) o).getEntry() : null;

 			if (otherEntry == null || !entry.equals(otherEntry))
 				return false;

 			String arch = otherEntry.getArch();
 			if (arch == null ? entry.getArch() != null : !arch.equals(entry.getArch()))
 				return false;
 			String os = otherEntry.getOS();
 			if (os == null ? entry.getOS() != null : !os.equals(entry.getOS()))
 				return false;
 			String ws = otherEntry.getWS();
 			if (ws == null ? entry.getWS() != null : !ws.equals(entry.getWS()))
 				return false;

 			return true;
 		}

 		@Override
 		public int hashCode() {
 			int hash = entry.hashCode();
 			if (entry.getArch() != null)
 				hash += entry.getArch().hashCode();
 			if (entry.getOS() != null)
 				hash += entry.getOS().hashCode();
 			if (entry.getWS() != null)
 				hash += entry.getWS().hashCode();
 			return hash;
 		}

 		public FeatureEntry getEntry() {
 			return entry;
 		}
 	}

 	private static final String LINE_SEPARATOR = "\n"; //$NON-NLS-1$
 	private static final String CLASS_EXTENSION = ".class"; //$NON-NLS-1$
 	private static final String JAR_EXTENSION = ".jar"; //$NON-NLS-1$
 	private static final String PROPERTIES_EXTENSION = ".properties"; //$NON-NLS-1$
 	private static final String MAPPINGS_EXTENSION = ".mappings"; //$NON-NLS-1$
 	private static final String PLUGIN_ID = "org.eclipse.equinox.p2.repository.tools"; //$NON-NLS-1$
 	private static final String DESTINATION_ARTIFACT_PREFIX = "destinationartifact"; //$NON-NLS-1$
 	private static final String SUFFIX_JAR = ".jar"; //$NON-NLS-1$
 	private static final String SOURCE_ARTIFACT_PREFIX = "sourceartifact"; //$NON-NLS-1$
 	private static final String OSGI_BUNDLE_CLASSIFIER = "osgi.bundle"; //$NON-NLS-1$
 	private static final String FEATURE_CLASSIFIER = "org.eclipse.update.feature"; //$NON-NLS-1$

 	private static final String META_INF = "meta-inf/"; //$NON-NLS-1$
 	private static final String DSA_EXT = ".dsa"; //$NON-NLS-1$
 	private static final String RSA_EXT = ".rsa"; //$NON-NLS-1$
 	private static final String SF_EXT = ".sf"; //$NON-NLS-1$

 	private String sourceLocation, destinationLocation, descriptorString;

 	public IStatus compare(IArtifactRepository source, IArtifactDescriptor sourceDescriptor, IArtifactRepository destination, IArtifactDescriptor destinationDescriptor) {
 		// Cache information for potential error messages
 		sourceLocation = URIUtil.toUnencodedString(sourceDescriptor.getRepository().getLocation());
 		destinationLocation = URIUtil.toUnencodedString(destinationDescriptor.getRepository().getLocation());
 		descriptorString = sourceDescriptor.toString();

 		String classifier1 = sourceDescriptor.getArtifactKey().getClassifier();
 		String classifier2 = destinationDescriptor.getArtifactKey().getClassifier();
 		if (!classifier1.equals(classifier2) || (!OSGI_BUNDLE_CLASSIFIER.equals(classifier1) && !FEATURE_CLASSIFIER.equals(classifier1))) {
 			return Status.OK_STATUS;
 		}

 		File firstTempFile = null;
 		File secondTempFile = null;
 		try {
 			firstTempFile = getLocalJarFile(source, sourceDescriptor, SOURCE_ARTIFACT_PREFIX);
 			secondTempFile = getLocalJarFile(destination, destinationDescriptor, DESTINATION_ARTIFACT_PREFIX);
 			if (classifier1.equals(OSGI_BUNDLE_CLASSIFIER))
 				return compare(firstTempFile, secondTempFile);
 			else if (classifier1.equals(FEATURE_CLASSIFIER))
 				return compareFeatures(firstTempFile, secondTempFile);
 		} catch (CoreException e) {
 			return e.getStatus();
 		} finally {
 			if (firstTempFile != null)
 				firstTempFile.delete();
 			if (secondTempFile != null)
 				secondTempFile.delete();
 		}
 		return Status.OK_STATUS;
 	}

 	public IStatus compareFeatures(File sourceFile, File destinationFile) {
 		FeatureParser parser = new FeatureParser();
 		Feature feature1 = parser.parse(sourceFile);
 		Feature feature2 = parser.parse(destinationFile);

 		MultiStatus parent = new MultiStatus(PLUGIN_ID, 0, NLS.bind(Messages.differentEntry, new String[] {descriptorString, sourceLocation, destinationLocation}), null);

 		if (!feature1.getId().equals(feature2.getId()))
 			parent.add(newErrorStatus(NLS.bind(Messages.featureIdsDontMatch, feature1.getId(), feature2.getId())));
 		if (!feature1.getVersion().equals(feature2.getVersion()))
 			parent.add(newErrorStatus(NLS.bind(Messages.featureVersionsDontMatch, feature1.getVersion(), feature2.getVersion())));

 		Map<FeatureEntryWrapper, FeatureEntry> entryMap = new HashMap<FeatureEntryWrapper, FeatureEntry>();
 		FeatureEntry[] entries1 = feature1.getEntries();
 		FeatureEntry[] entries2 = feature2.getEntries();

 		if (entries1.length != entries2.length)
 			parent.add(newErrorStatus(Messages.featureSize));

 		for (int i = 0; i < entries1.length; i++)
 			entryMap.put(new FeatureEntryWrapper(entries1[i]), entries1[i]);

 		for (int i = 0; i < entries2.length; i++) {
 			FeatureEntry firstEntry = entryMap.get(new FeatureEntryWrapper(entries2[i]));
 			if (firstEntry == null)
 				parent.add(newErrorStatus(NLS.bind(Messages.featureEntry, entries2[i])));
 			else {
 				if (firstEntry.isOptional() != entries2[i].isOptional())
 					parent.add(newErrorStatus(NLS.bind(Messages.featureEntryOptional, entries2[i])));
 				if (firstEntry.isUnpack() != entries2[i].isUnpack())
 					parent.add(newErrorStatus(NLS.bind(Messages.featureEntryUnpack, entries2[i])));
 				if (firstEntry.isRequires() && firstEntry.getMatch() != null && !firstEntry.getMatch().equals(entries2[i].getMatch()))
 					parent.add(newErrorStatus(NLS.bind(Messages.featureEntryMatch, entries2[i])));
 				if (firstEntry.getFilter() != null && !firstEntry.getFilter().equals(entries2[i].getFilter()))
 					parent.add(newErrorStatus(NLS.bind(Messages.featureEntryFilter, entries2[i])));
 			}
 		}

 		return parent.getChildren().length == 0 ? Status.OK_STATUS : parent;
 	}

 	public IStatus compare(File sourceFile, File destinationFile) {
 		ZipFile firstFile = null;
 		ZipFile secondFile = null;
 		try {
 			firstFile = new ZipFile(sourceFile);
 			secondFile = new ZipFile(destinationFile);
 			final int firstFileSize = firstFile.size();
 			final int secondFileSize = secondFile.size();
 			MultiStatus parent = new MultiStatus(PLUGIN_ID, 0, NLS.bind(Messages.differentEntry, new String[] {descriptorString, sourceLocation, destinationLocation}), null);

 			if (firstFileSize != secondFileSize) {
 				parent.add(newErrorStatus(NLS.bind(Messages.differentNumberOfEntries, new String[] {descriptorString, sourceLocation, Integer.toString(firstFileSize), destinationLocation, Integer.toString(secondFileSize)})));
 				return parent;
 			}
 			for (Enumeration<? extends ZipEntry> enumeration = firstFile.entries(); enumeration.hasMoreElements();) {
 				ZipEntry entry = enumeration.nextElement();
 				String entryName = entry.getName();
 				final ZipEntry entry2 = secondFile.getEntry(entryName);
 				IStatus result = null;
 				if (!entry.isDirectory() && entry2 != null) {
 					String lowerCase = entryName.toLowerCase();
 					if (isSigningEntry(lowerCase)) {
 						continue;
 					}

 					InputStream firstStream = null;
 					InputStream secondStream = null;
 					try {
 						firstStream = new BufferedInputStream(firstFile.getInputStream(entry));
 						secondStream = new BufferedInputStream(secondFile.getInputStream(entry2));
 						if (lowerCase.endsWith(CLASS_EXTENSION)) {
 							result = compareClasses(entryName, firstStream, entry.getSize(), secondStream, entry2.getSize());
 						} else if (lowerCase.endsWith(JAR_EXTENSION)) {
 							result = compareNestedJars(firstStream, entry.getSize(), secondStream, entry2.getSize(), entryName);
 						} else if (lowerCase.endsWith(PROPERTIES_EXTENSION) || lowerCase.endsWith(MAPPINGS_EXTENSION)) {
 							result = compareProperties(entryName, firstStream, secondStream);
 						} else if (entryName.equalsIgnoreCase(JarFile.MANIFEST_NAME)) {
 							result = compareManifest(firstStream, secondStream); //MANIFEST.MF file
 						} else {
 							long size1 = entry.getSize();
 							long size2 = entry2.getSize();
 							if (size1 != size2)
 								result = newErrorStatus(NLS.bind(Messages.binaryDifferentLength, new String[] {entryName, String.valueOf(Math.abs(size1 - size2))}));
 							else
 								result = compareBytes(entryName, firstStream, entry.getSize(), secondStream, entry2.getSize());
 						}
 					} finally {
 						Utility.close(firstStream);
 						Utility.close(secondStream);
 					}
 				} else if (!entry.isDirectory()) {
 					// missing entry, entry2 == null
 					result = newErrorStatus(NLS.bind(Messages.missingEntry, new String[] {entryName, descriptorString, sourceLocation}));
 				}

 				if (result != null && !result.isOK()) {
 					parent.add(result);
 					return parent;
 				}
 			}
 		} catch (IOException e) {
 			// missing entry
 			return newErrorStatus(NLS.bind(Messages.ioexception, new String[] {sourceFile.getAbsolutePath(), destinationFile.getAbsolutePath()}), e);
 		} finally {
 			Utility.close(firstFile);
 			Utility.close(secondFile);
 		}
 		return Status.OK_STATUS;
 	}

 	private IStatus compareManifest(InputStream firstStream, InputStream secondStream) throws IOException {
 		Manifest manifest = new Manifest(firstStream);
 		Manifest manifest2 = new Manifest(secondStream);

 		if (manifest == null || manifest2 == null)
 			return Status.OK_STATUS;

 		Attributes attributes = manifest.getMainAttributes();
 		Attributes attributes2 = manifest2.getMainAttributes();
 		if (attributes.size() != attributes2.size())
 			return newErrorStatus(NLS.bind(Messages.manifestDifferentSize, String.valueOf(Math.abs(attributes.size() - attributes2.size()))));
 		for (Entry<Object, Object> entry : attributes.entrySet()) {
 			Object value2 = attributes2.get(entry.getKey());
 			if (value2 == null) {
 				return newErrorStatus(NLS.bind(Messages.manifestMissingEntry, entry.getKey()));
 			}
 			if (!value2.equals(entry.getValue())) {
 				return newErrorStatus(NLS.bind(Messages.manifestDifferentValue, entry.getKey()));
 			}
 		}
 		return Status.OK_STATUS;
 	}

 	private IStatus compareClasses(String entryName, InputStream stream1, long size1, InputStream stream2, long size2) throws IOException {
 		Disassembler disassembler = new Disassembler();
 		byte[] firstEntryClassFileBytes = Utility.getInputStreamAsByteArray(stream1, (int) size1);
 		byte[] secondEntryClassFileBytes = Utility.getInputStreamAsByteArray(stream2, (int) size2);

 		String contentsFile1 = null;
 		try {
 			contentsFile1 = disassembler.disassemble(firstEntryClassFileBytes, LINE_SEPARATOR, Disassembler.DETAILED | Disassembler.COMPACT);
 		} catch (ClassFormatException e) {
 			// ignore
 		}
 		String contentsFile2 = null;
 		try {
 			contentsFile2 = disassembler.disassemble(secondEntryClassFileBytes, LINE_SEPARATOR, Disassembler.DETAILED | Disassembler.COMPACT);
 		} catch (ClassFormatException e) {
 			// ignore
 		}
 		if (contentsFile1 == null || contentsFile2 == null) {
 			// one of the two .class file (or both) is corrupted
 			if (contentsFile1 == null) {
 				if (contentsFile2 != null) {
 					// first .class file is corrupted and not the second one
 					return newErrorStatus(NLS.bind(Messages.classesDifferent, entryName));
 				}
 				// both .class files are corrupted and we need to do a byte comparison in case the .class file is corrupted on purpose
 				if (!Arrays.equals(firstEntryClassFileBytes, secondEntryClassFileBytes)) {
 					return newErrorStatus(NLS.bind(Messages.binaryFilesDifferent, entryName));
 				}
 				return Status.OK_STATUS;
 			}
 			// first .class file is not corrupted but the second one is
 			return newErrorStatus(NLS.bind(Messages.classesDifferent, entryName));
 		}
 		if (!contentsFile1.equals(contentsFile2)) {
 			return newErrorStatus(NLS.bind(Messages.classesDifferent, entryName));
 		}
 		return Status.OK_STATUS;
 	}

 	private IStatus compareNestedJars(InputStream stream1, long size1, InputStream stream2, long size2, String entry) throws IOException {
 		File firstTempFile = getLocalJarFile(stream1, entry, size1);
 		File secondTempFile = getLocalJarFile(stream2, entry, size2);

 		try {
 			return compare(firstTempFile, secondTempFile);
 		} finally {
 			if (firstTempFile != null)
 				firstTempFile.delete();
 			if (secondTempFile != null)
 				secondTempFile.delete();
 		}
 	}

 	private IStatus compareProperties(String entryName, InputStream stream1, InputStream stream2) {
 		Properties props1 = loadProperties(stream1);
 		Properties props2 = loadProperties(stream2);
 		if (props1.size() != props2.size())
 			return newErrorStatus(NLS.bind(Messages.propertiesSizesDifferent, entryName, String.valueOf(Math.abs(props1.size() - props2.size()))));

 		props1.keys();
 		for (Iterator<Object> iterator = props1.keySet().iterator(); iterator.hasNext();) {
 			String key = (String) iterator.next();
 			if (!props2.containsKey(key))
 				return newErrorStatus(NLS.bind(Messages.missingProperty, key, entryName));
 			String prop1 = props1.getProperty(key);
 			String prop2 = props2.getProperty(key);
 			if (!prop1.equals(prop2)) {
 				if (prop1.length() < 15 && prop2.length() < 15)
 					return newErrorStatus(NLS.bind(Messages.differentPropertyValueFull, new String[] {entryName, key, prop1, prop2}));
 				// strings are too long, report the first bit that is different
 				String[] diff = extractDifference(prop1, prop2);
 				return newErrorStatus(NLS.bind(Messages.differentPropertyValueFull, new String[] {entryName, key, diff[0], diff[1]}));
 			}

 		}
 		return Status.OK_STATUS;
 	}

 	/*
 	 * Given two different strings return the first segments of those
 	 * strings that illustrate the differences.
 	 */
 	private String[] extractDifference(String s1, String s2) {
 		for (int i = 0; i < s1.length() && i < s2.length(); i++) {
 			if (s1.charAt(i) != s2.charAt(i)) {
 				String result1, result2;
 				boolean truncated;
 				if (i > 3) {
 					truncated = (i + 7) < s1.length();
 					result1 = "..." + s1.substring(i - 3, truncated ? i + 7 : s1.length()) + (truncated ? "..." : ""); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
 					truncated = (i + 7) < s2.length();
 					result2 = "..." + s2.substring(i - 3, truncated ? i + 7 : s2.length()) + (truncated ? "..." : ""); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
 				} else {
 					truncated = (i + 10) < s1.length();
 					result1 = s1.substring(0, truncated ? i + 10 : s1.length()) + (truncated ? "..." : ""); //$NON-NLS-1$ //$NON-NLS-2$
 					truncated = (i + 10) < s2.length();
 					result2 = s2.substring(0, truncated ? i + 10 : s2.length()) + (truncated ? "..." : ""); //$NON-NLS-1$ //$NON-NLS-2$
 				}
 				return new String[] {result1, result2};
 			}
 		}
 		//no differences?
 		return new String[] {s1, s2};
 	}

 	private IStatus compareBytes(String entryName, InputStream firstStream, long size1, InputStream secondStream, long size2) throws IOException {
 		byte[] firstBytes = Utility.getInputStreamAsByteArray(firstStream, (int) size1);
 		byte[] secondBytes = Utility.getInputStreamAsByteArray(secondStream, (int) size2);
 		if (!Arrays.equals(firstBytes, secondBytes))
 			return newErrorStatus(NLS.bind(Messages.binaryFilesDifferent, entryName));
 		return Status.OK_STATUS;
 	}

 	private Properties loadProperties(InputStream input) {
 		Properties result = new Properties();
 		try {
 			result.load(input);
 		} catch (IOException e) {
 			//ignore
 		}
 		return result;
 	}

 	private String normalize(String entryName) {
 		StringBuffer buffer = new StringBuffer();
 		char[] chars = entryName.toCharArray();
 		for (int i = 0, max = chars.length; i < max; i++) {
 			char currentChar = chars[i];
 			if (!Character.isJavaIdentifierPart(currentChar)) {
 				buffer.append('_');
 			} else {
 				buffer.append(currentChar);
 			}
 		}
 		return String.valueOf(buffer);
 	}

 	private IStatus newErrorStatus(String message, Exception e) {
 		return new Status(IStatus.ERROR, PLUGIN_ID, message, e);
 	}

 	private IStatus newErrorStatus(String message) {
 		return newErrorStatus(message, null);
 	}

 	private File getLocalJarFile(IArtifactRepository repository, IArtifactDescriptor descriptor, String prefix) throws CoreException {
 		File file = null;
 		BufferedOutputStream stream = null;
 		try {
 			file = File.createTempFile(prefix, SUFFIX_JAR);
 			stream = new BufferedOutputStream(new FileOutputStream(file));
 			IStatus status = repository.getArtifact(descriptor, stream, new NullProgressMonitor());
 			if (!status.isOK())
 				throw new CoreException(status);
 			stream.flush();
 		} catch (FileNotFoundException e) {
 			throw new CoreException(newErrorStatus("FileNotFoundException", e)); //$NON-NLS-1$
 		} catch (IOException e) {
 			throw new CoreException(newErrorStatus("IOException", e)); //$NON-NLS-1$
 		} finally {
 			Utility.close(stream);
 		}
 		return file;
 	}

 	private File getLocalJarFile(InputStream inputStream, String entry, long size) throws IOException {
 		byte[] firstEntryClassFileBytes = Utility.getInputStreamAsByteArray(inputStream, (int) size);

 		File tempFile = null;
 		BufferedOutputStream stream = null;
 		try {
 			tempFile = File.createTempFile(SOURCE_ARTIFACT_PREFIX + normalize(entry), SUFFIX_JAR);
 			stream = new BufferedOutputStream(new FileOutputStream(tempFile));
 			stream.write(firstEntryClassFileBytes);
 			stream.flush();
 		} finally {
 			Utility.close(stream);
 		}
 		return tempFile;
 	}

 	private boolean isSigningEntry(String entry) {
 		return (entry.startsWith(META_INF) && (entry.endsWith(SF_EXT) || entry.endsWith(RSA_EXT) || entry.endsWith(DSA_EXT)));
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2009, 2012 IBM Corporation and others.
	* All rights reserved. This program and the accompanying materials
	* are made available under the terms of the Eclipse Public License v1.0
	* which accompanies this distribution, and is available at
	* http://www.eclipse.org/legal/epl-v10.html
	*
	* Contributors:
	* IBM Corporation - initial API and implementation
	*******************************************************************************/
	package org.eclipse.equinox.p2.internal.repository.comparator;

	import java.io.*;
	import java.util.*;
	import java.util.Map.Entry;
	import java.util.jar.*;
	import java.util.zip.ZipEntry;
	import java.util.zip.ZipFile;
	import org.eclipse.core.runtime.*;
	import org.eclipse.equinox.internal.p2.publisher.eclipse.FeatureParser;
	import org.eclipse.equinox.p2.internal.repository.comparator.java.*;
	import org.eclipse.equinox.p2.publisher.eclipse.Feature;
	import org.eclipse.equinox.p2.publisher.eclipse.FeatureEntry;
	import org.eclipse.equinox.p2.repository.artifact.IArtifactDescriptor;
	import org.eclipse.equinox.p2.repository.artifact.IArtifactRepository;
	import org.eclipse.equinox.p2.repository.tools.comparator.IArtifactComparator;
	import org.eclipse.osgi.util.NLS;

	/**
	* An artifact comparator that compares two JAR files. Class files are disassembled
	* and compared for equivalence, properties and manifest files are compared as such,
	* all other files are compared byte-for-byte.
	*/
	public class JarComparator implements IArtifactComparator {

	private static class FeatureEntryWrapper {
	private FeatureEntry entry;

	public FeatureEntryWrapper(FeatureEntry entry) {
	this.entry = entry;
	}

	@Override
	public boolean equals(Object o) {
	FeatureEntry otherEntry = (o instanceof FeatureEntryWrapper) ? ((FeatureEntryWrapper) o).getEntry() : null;

	if (otherEntry == null \|\| !entry.equals(otherEntry))
	return false;

	String arch = otherEntry.getArch();
	if (arch == null ? entry.getArch() != null : !arch.equals(entry.getArch()))
	return false;
	String os = otherEntry.getOS();
	if (os == null ? entry.getOS() != null : !os.equals(entry.getOS()))
	return false;
	String ws = otherEntry.getWS();
	if (ws == null ? entry.getWS() != null : !ws.equals(entry.getWS()))
	return false;

	return true;
	}

	@Override
	public int hashCode() {
	int hash = entry.hashCode();
	if (entry.getArch() != null)
	hash += entry.getArch().hashCode();
	if (entry.getOS() != null)
	hash += entry.getOS().hashCode();
	if (entry.getWS() != null)
	hash += entry.getWS().hashCode();
	return hash;
	}

	public FeatureEntry getEntry() {
	return entry;
	}
	}

	private static final String LINE_SEPARATOR = "\n"; //$NON-NLS-1$
	private static final String CLASS_EXTENSION = ".class"; //$NON-NLS-1$
	private static final String JAR_EXTENSION = ".jar"; //$NON-NLS-1$
	private static final String PROPERTIES_EXTENSION = ".properties"; //$NON-NLS-1$
	private static final String MAPPINGS_EXTENSION = ".mappings"; //$NON-NLS-1$
	private static final String PLUGIN_ID = "org.eclipse.equinox.p2.repository.tools"; //$NON-NLS-1$
	private static final String DESTINATION_ARTIFACT_PREFIX = "destinationartifact"; //$NON-NLS-1$
	private static final String SUFFIX_JAR = ".jar"; //$NON-NLS-1$
	private static final String SOURCE_ARTIFACT_PREFIX = "sourceartifact"; //$NON-NLS-1$
	private static final String OSGI_BUNDLE_CLASSIFIER = "osgi.bundle"; //$NON-NLS-1$
	private static final String FEATURE_CLASSIFIER = "org.eclipse.update.feature"; //$NON-NLS-1$

	private static final String META_INF = "meta-inf/"; //$NON-NLS-1$
	private static final String DSA_EXT = ".dsa"; //$NON-NLS-1$
	private static final String RSA_EXT = ".rsa"; //$NON-NLS-1$
	private static final String SF_EXT = ".sf"; //$NON-NLS-1$

	private String sourceLocation, destinationLocation, descriptorString;

	public IStatus compare(IArtifactRepository source, IArtifactDescriptor sourceDescriptor, IArtifactRepository destination, IArtifactDescriptor destinationDescriptor) {
	// Cache information for potential error messages
	sourceLocation = URIUtil.toUnencodedString(sourceDescriptor.getRepository().getLocation());
	destinationLocation = URIUtil.toUnencodedString(destinationDescriptor.getRepository().getLocation());
	descriptorString = sourceDescriptor.toString();

	String classifier1 = sourceDescriptor.getArtifactKey().getClassifier();
	String classifier2 = destinationDescriptor.getArtifactKey().getClassifier();
	if (!classifier1.equals(classifier2) \|\| (!OSGI_BUNDLE_CLASSIFIER.equals(classifier1) && !FEATURE_CLASSIFIER.equals(classifier1))) {
	return Status.OK_STATUS;
	}

	File firstTempFile = null;
	File secondTempFile = null;
	try {
	firstTempFile = getLocalJarFile(source, sourceDescriptor, SOURCE_ARTIFACT_PREFIX);
	secondTempFile = getLocalJarFile(destination, destinationDescriptor, DESTINATION_ARTIFACT_PREFIX);
	if (classifier1.equals(OSGI_BUNDLE_CLASSIFIER))
	return compare(firstTempFile, secondTempFile);
	else if (classifier1.equals(FEATURE_CLASSIFIER))
	return compareFeatures(firstTempFile, secondTempFile);
	} catch (CoreException e) {
	return e.getStatus();
	} finally {
	if (firstTempFile != null)
	firstTempFile.delete();
	if (secondTempFile != null)
	secondTempFile.delete();
	}
	return Status.OK_STATUS;
	}

	public IStatus compareFeatures(File sourceFile, File destinationFile) {
	FeatureParser parser = new FeatureParser();
	Feature feature1 = parser.parse(sourceFile);
	Feature feature2 = parser.parse(destinationFile);

	MultiStatus parent = new MultiStatus(PLUGIN_ID, 0, NLS.bind(Messages.differentEntry, new String[] {descriptorString, sourceLocation, destinationLocation}), null);

	if (!feature1.getId().equals(feature2.getId()))
	parent.add(newErrorStatus(NLS.bind(Messages.featureIdsDontMatch, feature1.getId(), feature2.getId())));
	if (!feature1.getVersion().equals(feature2.getVersion()))
	parent.add(newErrorStatus(NLS.bind(Messages.featureVersionsDontMatch, feature1.getVersion(), feature2.getVersion())));

	Map<FeatureEntryWrapper, FeatureEntry> entryMap = new HashMap<FeatureEntryWrapper, FeatureEntry>();
	FeatureEntry[] entries1 = feature1.getEntries();
	FeatureEntry[] entries2 = feature2.getEntries();

	if (entries1.length != entries2.length)
	parent.add(newErrorStatus(Messages.featureSize));

	for (int i = 0; i < entries1.length; i++)
	entryMap.put(new FeatureEntryWrapper(entries1[i]), entries1[i]);

	for (int i = 0; i < entries2.length; i++) {
	FeatureEntry firstEntry = entryMap.get(new FeatureEntryWrapper(entries2[i]));
	if (firstEntry == null)
	parent.add(newErrorStatus(NLS.bind(Messages.featureEntry, entries2[i])));
	else {
	if (firstEntry.isOptional() != entries2[i].isOptional())
	parent.add(newErrorStatus(NLS.bind(Messages.featureEntryOptional, entries2[i])));
	if (firstEntry.isUnpack() != entries2[i].isUnpack())
	parent.add(newErrorStatus(NLS.bind(Messages.featureEntryUnpack, entries2[i])));
	if (firstEntry.isRequires() && firstEntry.getMatch() != null && !firstEntry.getMatch().equals(entries2[i].getMatch()))
	parent.add(newErrorStatus(NLS.bind(Messages.featureEntryMatch, entries2[i])));
	if (firstEntry.getFilter() != null && !firstEntry.getFilter().equals(entries2[i].getFilter()))
	parent.add(newErrorStatus(NLS.bind(Messages.featureEntryFilter, entries2[i])));
	}
	}

	return parent.getChildren().length == 0 ? Status.OK_STATUS : parent;
	}

	public IStatus compare(File sourceFile, File destinationFile) {
	ZipFile firstFile = null;
	ZipFile secondFile = null;
	try {
	firstFile = new ZipFile(sourceFile);
	secondFile = new ZipFile(destinationFile);
	final int firstFileSize = firstFile.size();
	final int secondFileSize = secondFile.size();
	MultiStatus parent = new MultiStatus(PLUGIN_ID, 0, NLS.bind(Messages.differentEntry, new String[] {descriptorString, sourceLocation, destinationLocation}), null);

	if (firstFileSize != secondFileSize) {
	parent.add(newErrorStatus(NLS.bind(Messages.differentNumberOfEntries, new String[] {descriptorString, sourceLocation, Integer.toString(firstFileSize), destinationLocation, Integer.toString(secondFileSize)})));
	return parent;
	}
	for (Enumeration<? extends ZipEntry> enumeration = firstFile.entries(); enumeration.hasMoreElements();) {
	ZipEntry entry = enumeration.nextElement();
	String entryName = entry.getName();
	final ZipEntry entry2 = secondFile.getEntry(entryName);
	IStatus result = null;
	if (!entry.isDirectory() && entry2 != null) {
	String lowerCase = entryName.toLowerCase();
	if (isSigningEntry(lowerCase)) {
	continue;
	}

	InputStream firstStream = null;
	InputStream secondStream = null;
	try {
	firstStream = new BufferedInputStream(firstFile.getInputStream(entry));
	secondStream = new BufferedInputStream(secondFile.getInputStream(entry2));
	if (lowerCase.endsWith(CLASS_EXTENSION)) {
	result = compareClasses(entryName, firstStream, entry.getSize(), secondStream, entry2.getSize());
	} else if (lowerCase.endsWith(JAR_EXTENSION)) {
	result = compareNestedJars(firstStream, entry.getSize(), secondStream, entry2.getSize(), entryName);
	} else if (lowerCase.endsWith(PROPERTIES_EXTENSION) \|\| lowerCase.endsWith(MAPPINGS_EXTENSION)) {
	result = compareProperties(entryName, firstStream, secondStream);
	} else if (entryName.equalsIgnoreCase(JarFile.MANIFEST_NAME)) {
	result = compareManifest(firstStream, secondStream); //MANIFEST.MF file
	} else {
	long size1 = entry.getSize();
	long size2 = entry2.getSize();
	if (size1 != size2)
	result = newErrorStatus(NLS.bind(Messages.binaryDifferentLength, new String[] {entryName, String.valueOf(Math.abs(size1 - size2))}));
	else
	result = compareBytes(entryName, firstStream, entry.getSize(), secondStream, entry2.getSize());
	}
	} finally {
	Utility.close(firstStream);
	Utility.close(secondStream);
	}
	} else if (!entry.isDirectory()) {
	// missing entry, entry2 == null
	result = newErrorStatus(NLS.bind(Messages.missingEntry, new String[] {entryName, descriptorString, sourceLocation}));
	}

	if (result != null && !result.isOK()) {
	parent.add(result);
	return parent;
	}
	}
	} catch (IOException e) {
	// missing entry
	return newErrorStatus(NLS.bind(Messages.ioexception, new String[] {sourceFile.getAbsolutePath(), destinationFile.getAbsolutePath()}), e);
	} finally {
	Utility.close(firstFile);
	Utility.close(secondFile);
	}
	return Status.OK_STATUS;
	}

	private IStatus compareManifest(InputStream firstStream, InputStream secondStream) throws IOException {
	Manifest manifest = new Manifest(firstStream);
	Manifest manifest2 = new Manifest(secondStream);

	if (manifest == null \|\| manifest2 == null)
	return Status.OK_STATUS;

	Attributes attributes = manifest.getMainAttributes();
	Attributes attributes2 = manifest2.getMainAttributes();
	if (attributes.size() != attributes2.size())
	return newErrorStatus(NLS.bind(Messages.manifestDifferentSize, String.valueOf(Math.abs(attributes.size() - attributes2.size()))));
	for (Entry<Object, Object> entry : attributes.entrySet()) {
	Object value2 = attributes2.get(entry.getKey());
	if (value2 == null) {
	return newErrorStatus(NLS.bind(Messages.manifestMissingEntry, entry.getKey()));
	}
	if (!value2.equals(entry.getValue())) {
	return newErrorStatus(NLS.bind(Messages.manifestDifferentValue, entry.getKey()));
	}
	}
	return Status.OK_STATUS;
	}

	private IStatus compareClasses(String entryName, InputStream stream1, long size1, InputStream stream2, long size2) throws IOException {
	Disassembler disassembler = new Disassembler();
	byte[] firstEntryClassFileBytes = Utility.getInputStreamAsByteArray(stream1, (int) size1);
	byte[] secondEntryClassFileBytes = Utility.getInputStreamAsByteArray(stream2, (int) size2);

	String contentsFile1 = null;
	try {
	contentsFile1 = disassembler.disassemble(firstEntryClassFileBytes, LINE_SEPARATOR, Disassembler.DETAILED \| Disassembler.COMPACT);
	} catch (ClassFormatException e) {
	// ignore
	}
	String contentsFile2 = null;
	try {
	contentsFile2 = disassembler.disassemble(secondEntryClassFileBytes, LINE_SEPARATOR, Disassembler.DETAILED \| Disassembler.COMPACT);
	} catch (ClassFormatException e) {
	// ignore
	}
	if (contentsFile1 == null \|\| contentsFile2 == null) {
	// one of the two .class file (or both) is corrupted
	if (contentsFile1 == null) {
	if (contentsFile2 != null) {
	// first .class file is corrupted and not the second one
	return newErrorStatus(NLS.bind(Messages.classesDifferent, entryName));
	}
	// both .class files are corrupted and we need to do a byte comparison in case the .class file is corrupted on purpose
	if (!Arrays.equals(firstEntryClassFileBytes, secondEntryClassFileBytes)) {
	return newErrorStatus(NLS.bind(Messages.binaryFilesDifferent, entryName));
	}
	return Status.OK_STATUS;
	}
	// first .class file is not corrupted but the second one is
	return newErrorStatus(NLS.bind(Messages.classesDifferent, entryName));
	}
	if (!contentsFile1.equals(contentsFile2)) {
	return newErrorStatus(NLS.bind(Messages.classesDifferent, entryName));
	}
	return Status.OK_STATUS;
	}

	private IStatus compareNestedJars(InputStream stream1, long size1, InputStream stream2, long size2, String entry) throws IOException {
	File firstTempFile = getLocalJarFile(stream1, entry, size1);
	File secondTempFile = getLocalJarFile(stream2, entry, size2);

	try {
	return compare(firstTempFile, secondTempFile);
	} finally {
	if (firstTempFile != null)
	firstTempFile.delete();
	if (secondTempFile != null)
	secondTempFile.delete();
	}
	}

	private IStatus compareProperties(String entryName, InputStream stream1, InputStream stream2) {
	Properties props1 = loadProperties(stream1);
	Properties props2 = loadProperties(stream2);
	if (props1.size() != props2.size())
	return newErrorStatus(NLS.bind(Messages.propertiesSizesDifferent, entryName, String.valueOf(Math.abs(props1.size() - props2.size()))));

	props1.keys();
	for (Iterator<Object> iterator = props1.keySet().iterator(); iterator.hasNext();) {
	String key = (String) iterator.next();
	if (!props2.containsKey(key))
	return newErrorStatus(NLS.bind(Messages.missingProperty, key, entryName));
	String prop1 = props1.getProperty(key);
	String prop2 = props2.getProperty(key);
	if (!prop1.equals(prop2)) {
	if (prop1.length() < 15 && prop2.length() < 15)
	return newErrorStatus(NLS.bind(Messages.differentPropertyValueFull, new String[] {entryName, key, prop1, prop2}));
	// strings are too long, report the first bit that is different
	String[] diff = extractDifference(prop1, prop2);
	return newErrorStatus(NLS.bind(Messages.differentPropertyValueFull, new String[] {entryName, key, diff[0], diff[1]}));
	}

	}
	return Status.OK_STATUS;
	}

	/*
	* Given two different strings return the first segments of those
	* strings that illustrate the differences.
	*/
	private String[] extractDifference(String s1, String s2) {
	for (int i = 0; i < s1.length() && i < s2.length(); i++) {
	if (s1.charAt(i) != s2.charAt(i)) {
	String result1, result2;
	boolean truncated;
	if (i > 3) {
	truncated = (i + 7) < s1.length();
	result1 = "..." + s1.substring(i - 3, truncated ? i + 7 : s1.length()) + (truncated ? "..." : ""); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
	truncated = (i + 7) < s2.length();
	result2 = "..." + s2.substring(i - 3, truncated ? i + 7 : s2.length()) + (truncated ? "..." : ""); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
	} else {
	truncated = (i + 10) < s1.length();
	result1 = s1.substring(0, truncated ? i + 10 : s1.length()) + (truncated ? "..." : ""); //$NON-NLS-1$ //$NON-NLS-2$
	truncated = (i + 10) < s2.length();
	result2 = s2.substring(0, truncated ? i + 10 : s2.length()) + (truncated ? "..." : ""); //$NON-NLS-1$ //$NON-NLS-2$
	}
	return new String[] {result1, result2};
	}
	}
	//no differences?
	return new String[] {s1, s2};
	}

	private IStatus compareBytes(String entryName, InputStream firstStream, long size1, InputStream secondStream, long size2) throws IOException {
	byte[] firstBytes = Utility.getInputStreamAsByteArray(firstStream, (int) size1);
	byte[] secondBytes = Utility.getInputStreamAsByteArray(secondStream, (int) size2);
	if (!Arrays.equals(firstBytes, secondBytes))
	return newErrorStatus(NLS.bind(Messages.binaryFilesDifferent, entryName));
	return Status.OK_STATUS;
	}

	private Properties loadProperties(InputStream input) {
	Properties result = new Properties();
	try {
	result.load(input);
	} catch (IOException e) {
	//ignore
	}
	return result;
	}

	private String normalize(String entryName) {
	StringBuffer buffer = new StringBuffer();
	char[] chars = entryName.toCharArray();
	for (int i = 0, max = chars.length; i < max; i++) {
	char currentChar = chars[i];
	if (!Character.isJavaIdentifierPart(currentChar)) {
	buffer.append('_');
	} else {
	buffer.append(currentChar);
	}
	}
	return String.valueOf(buffer);
	}

	private IStatus newErrorStatus(String message, Exception e) {
	return new Status(IStatus.ERROR, PLUGIN_ID, message, e);
	}

	private IStatus newErrorStatus(String message) {
	return newErrorStatus(message, null);
	}

	private File getLocalJarFile(IArtifactRepository repository, IArtifactDescriptor descriptor, String prefix) throws CoreException {
	File file = null;
	BufferedOutputStream stream = null;
	try {
	file = File.createTempFile(prefix, SUFFIX_JAR);
	stream = new BufferedOutputStream(new FileOutputStream(file));
	IStatus status = repository.getArtifact(descriptor, stream, new NullProgressMonitor());
	if (!status.isOK())
	throw new CoreException(status);
	stream.flush();
	} catch (FileNotFoundException e) {
	throw new CoreException(newErrorStatus("FileNotFoundException", e)); //$NON-NLS-1$
	} catch (IOException e) {
	throw new CoreException(newErrorStatus("IOException", e)); //$NON-NLS-1$
	} finally {
	Utility.close(stream);
	}
	return file;
	}

	private File getLocalJarFile(InputStream inputStream, String entry, long size) throws IOException {
	byte[] firstEntryClassFileBytes = Utility.getInputStreamAsByteArray(inputStream, (int) size);

	File tempFile = null;
	BufferedOutputStream stream = null;
	try {
	tempFile = File.createTempFile(SOURCE_ARTIFACT_PREFIX + normalize(entry), SUFFIX_JAR);
	stream = new BufferedOutputStream(new FileOutputStream(tempFile));
	stream.write(firstEntryClassFileBytes);
	stream.flush();
	} finally {
	Utility.close(stream);
	}
	return tempFile;
	}

	private boolean isSigningEntry(String entry) {
	return (entry.startsWith(META_INF) && (entry.endsWith(SF_EXT) \|\| entry.endsWith(RSA_EXT) \|\| entry.endsWith(DSA_EXT)));
	}
	}