bundles/org.eclipse.equinox.p2.ui.sdk.scheduler/src/org/eclipse/equinox/internal/p2/ui/sdk/scheduler/PreviousConfigurationFinder.java - equinox/rt.equinox.p2 - Git at Google

 /*******************************************************************************
  * Copyright (c) 2013, 2020 Ericsson AB and others.
  *
  * This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License 2.0
  * which accompanies this distribution, and is available at
  * https://www.eclipse.org/legal/epl-2.0/
  *
  * SPDX-License-Identifier: EPL-2.0
  *
  * Contributors:
  *     Ericsson AB - initial API and implementation
  *     Ericsson AB (Hamdan Msheik) - bug- 432167
  *******************************************************************************/
 package org.eclipse.equinox.internal.p2.ui.sdk.scheduler;

 import java.io.*;
 import java.util.*;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 import org.eclipse.core.runtime.Platform;
 import org.eclipse.equinox.internal.p2.touchpoint.eclipse.AgentFromInstall;
 import org.eclipse.equinox.p2.core.IProvisioningAgent;

 public class PreviousConfigurationFinder {

 	private static final Pattern path = Pattern.compile("(.+?)_{1}?([0-9\\.]+)_{1}?(\\d+)(_*?([^_].*)|$)"); //$NON-NLS-1$

 	public static class Identifier implements Comparable<Identifier> {
 		private static final String DELIM = ". _-"; //$NON-NLS-1$
 		private int major, minor, service;

 		public Identifier(int major, int minor, int service) {
 			super();
 			this.major = major;
 			this.minor = minor;
 			this.service = service;
 		}

 		/**
 		 * @throws NumberFormatException if cannot parse the major and minor version
 		 *                               components
 		 */
 		Identifier(String versionString) {
 			super();
 			StringTokenizer tokenizer = new StringTokenizer(versionString, DELIM);

 			// major
 			if (tokenizer.hasMoreTokens())
 				major = Integer.parseInt(tokenizer.nextToken());

 			// minor
 			if (tokenizer.hasMoreTokens())
 				minor = Integer.parseInt(tokenizer.nextToken());

 			try {
 				// service
 				if (tokenizer.hasMoreTokens())
 					service = Integer.parseInt(tokenizer.nextToken());
 			} catch (NumberFormatException nfe) {
 				// ignore the service qualifier in that case and default to 0
 				// this will allow us to tolerate other non-conventional version numbers
 			}
 		}

 		/**
 		 * Returns true if this id is considered to be greater than or equal to the
 		 * given baseline. e.g. 1.2.9 >= 1.3.1 -> false 1.3.0 >= 1.3.1 -> false 1.3.1 >=
 		 * 1.3.1 -> true 1.3.2 >= 1.3.1 -> true 2.0.0 >= 1.3.1 -> true
 		 */
 		boolean isGreaterEqualTo(Identifier minimum) {
 			if (major < minimum.major)
 				return false;
 			if (major > minimum.major)
 				return true;
 			// major numbers are equivalent so check minor
 			if (minor < minimum.minor)
 				return false;
 			if (minor > minimum.minor)
 				return true;
 			// minor numbers are equivalent so check service
 			return service >= minimum.service;
 		}

 		@Override
 		public boolean equals(Object other) {
 			if (!(other instanceof Identifier))
 				return false;
 			Identifier o = (Identifier) other;
 			if (major == o.major && minor == o.minor && service == o.service)
 				return true;
 			return false;
 		}

 		@Override
 		public String toString() {
 			return "" + major + '.' + minor + '.' + service; //$NON-NLS-1$
 		}

 		@Override
 		public int compareTo(Identifier o) {

 			if (o != null) {
 				if (major < o.major) {
 					return -1;
 				} else if (major > o.major) {
 					return 1;
 				} else if (minor < o.minor) {
 					return -1;
 				} else if (minor > o.minor) {
 					return 1;
 				} else if (service < o.service) {
 					return -1;
 				} else if (service > o.service) {
 					return 1;
 				} else {
 					return 0;
 				}
 			}

 			return 1;
 		}
 	}

 	public static class ConfigurationDescriptor {
 		String productId;
 		Identifier version;
 		String installPathHashcode;
 		File configFolder;
 		String os_ws_arch;

 		public ConfigurationDescriptor(String productId, Identifier version, String installPathHashcode,
 				String platformConfig, File configFolder) {
 			this.productId = productId;
 			this.version = version;
 			this.installPathHashcode = installPathHashcode;
 			this.configFolder = configFolder;
 			this.os_ws_arch = platformConfig;
 		}

 		public String getProductId() {
 			return productId;
 		}

 		public Identifier getVersion() {
 			return version;
 		}

 		public String getInstallPathHashcode() {
 			return installPathHashcode;
 		}

 		public File getConfig() {
 			return configFolder;
 		}

 		public String getPlatformConfig() {
 			return os_ws_arch;
 		}
 	}

 	public static class ConfigurationDescriptorComparator implements Comparator<ConfigurationDescriptor> {

 		// compare ConfigurationDescriptor according to their versions and when equals
 		// according to their lastModified field
 		@Override
 		public int compare(ConfigurationDescriptor o1, ConfigurationDescriptor o2) {
 			int result = -1;
 			if (o1 != null && o2 != null) {
 				if (o1.getVersion().compareTo(o2.getVersion()) != 0) {
 					result = o1.getVersion().compareTo(o2.getVersion());
 				} else {
 					if (o1.getConfig().lastModified() > o2.getConfig().lastModified()) {
 						result = 1;
 					} else if (o1.getConfig().lastModified() < o2.getConfig().lastModified()) {
 						result = -1;
 					} else
 						result = 0;
 				}
 			} else if (o1 == null) {
 				result = -1;
 			} else if (o2 == null) {
 				result = 1;
 			}
 			return result;
 		}

 	}

 	private File currentConfig;

 	public PreviousConfigurationFinder(File currentConfiguration) {
 		currentConfig = currentConfiguration;
 	}

 	public ConfigurationDescriptor extractConfigurationData(File candidate) {
 		Matcher m = path.matcher(candidate.getName());
 		if (!m.matches())
 			return null;
 		return new ConfigurationDescriptor(m.group(1), new Identifier(m.group(2)), m.group(3), m.group(5),
 				candidate.getAbsoluteFile());
 	}

 	public IProvisioningAgent findPreviousInstalls(File searchRoot, File installFolder) {
 		List<ConfigurationDescriptor> potentialConfigurations = readPreviousConfigurations(searchRoot);
 		ConfigurationDescriptor runningConfiguration = getConfigdataFromProductFile(installFolder);
 		if (runningConfiguration == null)
 			return null;
 		ConfigurationDescriptor match = findMostRelevantConfigurationFromInstallHashDir(potentialConfigurations,
 				runningConfiguration);
 		if (match == null)
 			match = findMostRelevantConfigurationFromProductId(potentialConfigurations, runningConfiguration);
 		if (match == null)
 			match = findSpecifiedConfiguration(searchRoot);
 		if (match == null)
 			return null;
 		return AgentFromInstall.createAgentFrom(AutomaticUpdatePlugin.getDefault().getAgentProvider(), null,
 				new File(match.getConfig(), "configuration"), null); //$NON-NLS-1$

 	}

 	public ConfigurationDescriptor findSpecifiedConfiguration(File searchRoot) {
 		final String prefixesAsString = System.getProperty("p2.forcedMigrationLocation"); //$NON-NLS-1$
 		if (prefixesAsString == null)
 			return null;

 		String[] prefixes = prefixesAsString.split(","); //$NON-NLS-1$
 		for (String prefix : prefixes) {
 			final String p = prefix;
 			File[] match = searchRoot.listFiles((FileFilter) candidate -> {
 				if (!candidate.isDirectory())
 					return false;
 				if (currentConfig.equals(candidate))
 					return false;
 				return candidate.getName().contains(p);
 			});
 			if (match.length != 0)
 				return new ConfigurationDescriptor("unknown", new Identifier("0.0.0"), "unknown", "unknown", match[0]); //$NON-NLS-1$//$NON-NLS-2$//$NON-NLS-3$//$NON-NLS-4$
 		}
 		return null;
 	}

 	private ConfigurationDescriptor getConfigdataFromProductFile(File installFolder) {
 		Object[] productFileInfo = loadEclipseProductFile(installFolder);
 		// Contrarily to the runtime, when the .eclipseproduct can't be found, we don't
 		// fallback to org.eclipse.platform.
 		if (productFileInfo.length == 0)
 			return null;
 		return new ConfigurationDescriptor((String) productFileInfo[0], (Identifier) productFileInfo[1],
 				getInstallDirHash(installFolder),
 				Platform.getOS() + '_' + Platform.getWS() + '_' + Platform.getOSArch(), null);
 	}

 	public ConfigurationDescriptor findMostRelevantConfigurationFromInstallHashDir(
 			List<ConfigurationDescriptor> configurations, ConfigurationDescriptor configToMatch) {
 		ConfigurationDescriptor bestMatch = null;
 		int numberOfcriteriaMet = 0;
 		for (ConfigurationDescriptor candidate : configurations) {
 			int criteriaMet = 0;
 			if (!candidate.getInstallPathHashcode().equals(configToMatch.getInstallPathHashcode())) {
 				continue;
 			}
 			criteriaMet++;

 			if (configToMatch.getProductId().equals(candidate.getProductId()) && //
 					configToMatch.getPlatformConfig().equals(candidate.getPlatformConfig()) && //
 					(!candidate.getVersion().isGreaterEqualTo(configToMatch.getVersion()))) {
 				// We have a match
 				criteriaMet++;
 			}

 			if (criteriaMet == 0)
 				continue;
 			if (criteriaMet > numberOfcriteriaMet) {
 				bestMatch = candidate;
 				numberOfcriteriaMet = criteriaMet;
 			} else if (criteriaMet == numberOfcriteriaMet) {
 				if (bestMatch.getVersion().equals(candidate.getVersion())) {
 					if (bestMatch.getConfig().lastModified() < candidate.getConfig().lastModified()) {
 						bestMatch = candidate;
 					}
 				} else {
 					if (candidate.getVersion().isGreaterEqualTo(bestMatch.getVersion()))
 						bestMatch = candidate;
 				}
 			}
 		}
 		return bestMatch;
 	}

 	// Out of a set of configuration, find the one with the most similar product
 	// info.
 	public ConfigurationDescriptor findMostRelevantConfigurationFromProductId(
 			List<ConfigurationDescriptor> configurations, ConfigurationDescriptor configToMatch) {
 		ConfigurationDescriptor bestMatch = null;

 		List<ConfigurationDescriptor> candidates = new ArrayList<>();
 		List<ConfigurationDescriptor> candidatesWithUnkonwArchitecture = new ArrayList<>();
 		for (ConfigurationDescriptor candidate : configurations) {
 			if (configToMatch.getProductId().equals(candidate.getProductId())
 					&& configToMatch.getVersion().isGreaterEqualTo(candidate.getVersion())) {
 				if (configToMatch.getPlatformConfig().equals(candidate.getPlatformConfig())) {
 					candidates.add(candidate);
 				} else { // candidate.getPlatformConfig() returns null in legacy installation prior to
 							// 4.x.x releases
 					candidatesWithUnkonwArchitecture.add(candidate);
 				}
 			}
 		}

 		if (!candidates.isEmpty()) {
 			candidates.sort(new ConfigurationDescriptorComparator());
 			bestMatch = candidates.get(candidates.size() - 1);
 		}

 		if (bestMatch == null) {
 			if (!candidatesWithUnkonwArchitecture.isEmpty()) {
 				candidatesWithUnkonwArchitecture.sort(new ConfigurationDescriptorComparator());
 				bestMatch = candidatesWithUnkonwArchitecture.get(candidatesWithUnkonwArchitecture.size() - 1);
 			}
 		}

 		return bestMatch;
 	}

 	// Load the .eclipseproduct file in the base of the installation. This logic is
 	// very similar to the one found in the launcher
 	private Object[] loadEclipseProductFile(File installDir) {
 		final String ECLIPSE = "eclipse"; //$NON-NLS-1$
 		final String PRODUCT_SITE_MARKER = ".eclipseproduct"; //$NON-NLS-1$
 		final String PRODUCT_SITE_ID = "id"; //$NON-NLS-1$
 		final String PRODUCT_SITE_VERSION = "version"; //$NON-NLS-1$

 		File eclipseProduct = new File(installDir, PRODUCT_SITE_MARKER);
 		String appId = null;
 		Identifier appVersion = null;
 		if (eclipseProduct.exists()) {
 			Properties props = new Properties();
 			try (FileInputStream is = new FileInputStream(eclipseProduct)) {
 				props.load(is);
 				appId = props.getProperty(PRODUCT_SITE_ID);
 				if (appId == null || appId.trim().length() == 0)
 					appId = ECLIPSE;
 				String version = props.getProperty(PRODUCT_SITE_VERSION);
 				if (version == null || version.trim().length() == 0)
 					appVersion = new Identifier(0, 0, 0);
 				else
 					appVersion = new Identifier(version);
 			} catch (IOException e) {
 				return new String[0];
 			}
 		} else {
 			return new String[0];
 		}
 		return new Object[] { appId, appVersion };
 	}

 	// Iterate through a folder to look for potential configuration folders and
 	// reify them.
 	public List<ConfigurationDescriptor> readPreviousConfigurations(File configurationFolder) {
 		File[] candidates = configurationFolder.listFiles();
 		List<ConfigurationDescriptor> configurations = new ArrayList<>(candidates.length);
 		for (File candidate : candidates) {
 			if (!candidate.isDirectory())
 				continue;
 			if (candidate.equals(currentConfig))
 				continue;
 			ConfigurationDescriptor tmp = extractConfigurationData(candidate);
 			if (tmp != null)
 				configurations.add(tmp);
 		}
 		return configurations;
 	}

 	// This code computes the hashCode of the install location.
 	// This is a simplified version of the code that the launcher executes.
 	private String getInstallDirHash(File installFolder) {
 		try {
 			return Integer.toString(installFolder.getCanonicalPath().hashCode());
 		} catch (IOException e) {
 			return ""; //$NON-NLS-1$
 		}
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2013, 2020 Ericsson AB and others.
	*
	* This program and the accompanying materials
	* are made available under the terms of the Eclipse Public License 2.0
	* which accompanies this distribution, and is available at
	* https://www.eclipse.org/legal/epl-2.0/
	*
	* SPDX-License-Identifier: EPL-2.0
	*
	* Contributors:
	* Ericsson AB - initial API and implementation
	* Ericsson AB (Hamdan Msheik) - bug- 432167
	*******************************************************************************/
	package org.eclipse.equinox.internal.p2.ui.sdk.scheduler;

	import java.io.*;
	import java.util.*;
	import java.util.regex.Matcher;
	import java.util.regex.Pattern;
	import org.eclipse.core.runtime.Platform;
	import org.eclipse.equinox.internal.p2.touchpoint.eclipse.AgentFromInstall;
	import org.eclipse.equinox.p2.core.IProvisioningAgent;

	public class PreviousConfigurationFinder {

	private static final Pattern path = Pattern.compile("(.+?)_{1}?([0-9\\.]+)_{1}?(\\d+)(_?([^_].)\|$)"); //$NON-NLS-1$

	public static class Identifier implements Comparable<Identifier> {
	private static final String DELIM = ". _-"; //$NON-NLS-1$
	private int major, minor, service;

	public Identifier(int major, int minor, int service) {
	super();
	this.major = major;
	this.minor = minor;
	this.service = service;
	}

	/**
	* @throws NumberFormatException if cannot parse the major and minor version
	* components
	*/
	Identifier(String versionString) {
	super();
	StringTokenizer tokenizer = new StringTokenizer(versionString, DELIM);

	// major
	if (tokenizer.hasMoreTokens())
	major = Integer.parseInt(tokenizer.nextToken());

	// minor
	if (tokenizer.hasMoreTokens())
	minor = Integer.parseInt(tokenizer.nextToken());

	try {
	// service
	if (tokenizer.hasMoreTokens())
	service = Integer.parseInt(tokenizer.nextToken());
	} catch (NumberFormatException nfe) {
	// ignore the service qualifier in that case and default to 0
	// this will allow us to tolerate other non-conventional version numbers
	}
	}

	/**
	* Returns true if this id is considered to be greater than or equal to the
	* given baseline. e.g. 1.2.9 >= 1.3.1 -> false 1.3.0 >= 1.3.1 -> false 1.3.1 >=
	* 1.3.1 -> true 1.3.2 >= 1.3.1 -> true 2.0.0 >= 1.3.1 -> true
	*/
	boolean isGreaterEqualTo(Identifier minimum) {
	if (major < minimum.major)
	return false;
	if (major > minimum.major)
	return true;
	// major numbers are equivalent so check minor
	if (minor < minimum.minor)
	return false;
	if (minor > minimum.minor)
	return true;
	// minor numbers are equivalent so check service
	return service >= minimum.service;
	}

	@Override
	public boolean equals(Object other) {
	if (!(other instanceof Identifier))
	return false;
	Identifier o = (Identifier) other;
	if (major == o.major && minor == o.minor && service == o.service)
	return true;
	return false;
	}

	@Override
	public String toString() {
	return "" + major + '.' + minor + '.' + service; //$NON-NLS-1$
	}

	@Override
	public int compareTo(Identifier o) {

	if (o != null) {
	if (major < o.major) {
	return -1;
	} else if (major > o.major) {
	return 1;
	} else if (minor < o.minor) {
	return -1;
	} else if (minor > o.minor) {
	return 1;
	} else if (service < o.service) {
	return -1;
	} else if (service > o.service) {
	return 1;
	} else {
	return 0;
	}
	}

	return 1;
	}
	}

	public static class ConfigurationDescriptor {
	String productId;
	Identifier version;
	String installPathHashcode;
	File configFolder;
	String os_ws_arch;

	public ConfigurationDescriptor(String productId, Identifier version, String installPathHashcode,
	String platformConfig, File configFolder) {
	this.productId = productId;
	this.version = version;
	this.installPathHashcode = installPathHashcode;
	this.configFolder = configFolder;
	this.os_ws_arch = platformConfig;
	}

	public String getProductId() {
	return productId;
	}

	public Identifier getVersion() {
	return version;
	}

	public String getInstallPathHashcode() {
	return installPathHashcode;
	}

	public File getConfig() {
	return configFolder;
	}

	public String getPlatformConfig() {
	return os_ws_arch;
	}
	}

	public static class ConfigurationDescriptorComparator implements Comparator<ConfigurationDescriptor> {

	// compare ConfigurationDescriptor according to their versions and when equals
	// according to their lastModified field
	@Override
	public int compare(ConfigurationDescriptor o1, ConfigurationDescriptor o2) {
	int result = -1;
	if (o1 != null && o2 != null) {
	if (o1.getVersion().compareTo(o2.getVersion()) != 0) {
	result = o1.getVersion().compareTo(o2.getVersion());
	} else {
	if (o1.getConfig().lastModified() > o2.getConfig().lastModified()) {
	result = 1;
	} else if (o1.getConfig().lastModified() < o2.getConfig().lastModified()) {
	result = -1;
	} else
	result = 0;
	}
	} else if (o1 == null) {
	result = -1;
	} else if (o2 == null) {
	result = 1;
	}
	return result;
	}

	}

	private File currentConfig;

	public PreviousConfigurationFinder(File currentConfiguration) {
	currentConfig = currentConfiguration;
	}

	public ConfigurationDescriptor extractConfigurationData(File candidate) {
	Matcher m = path.matcher(candidate.getName());
	if (!m.matches())
	return null;
	return new ConfigurationDescriptor(m.group(1), new Identifier(m.group(2)), m.group(3), m.group(5),
	candidate.getAbsoluteFile());
	}

	public IProvisioningAgent findPreviousInstalls(File searchRoot, File installFolder) {
	List<ConfigurationDescriptor> potentialConfigurations = readPreviousConfigurations(searchRoot);
	ConfigurationDescriptor runningConfiguration = getConfigdataFromProductFile(installFolder);
	if (runningConfiguration == null)
	return null;
	ConfigurationDescriptor match = findMostRelevantConfigurationFromInstallHashDir(potentialConfigurations,
	runningConfiguration);
	if (match == null)
	match = findMostRelevantConfigurationFromProductId(potentialConfigurations, runningConfiguration);
	if (match == null)
	match = findSpecifiedConfiguration(searchRoot);
	if (match == null)
	return null;
	return AgentFromInstall.createAgentFrom(AutomaticUpdatePlugin.getDefault().getAgentProvider(), null,
	new File(match.getConfig(), "configuration"), null); //$NON-NLS-1$

	}

	public ConfigurationDescriptor findSpecifiedConfiguration(File searchRoot) {
	final String prefixesAsString = System.getProperty("p2.forcedMigrationLocation"); //$NON-NLS-1$
	if (prefixesAsString == null)
	return null;

	String[] prefixes = prefixesAsString.split(","); //$NON-NLS-1$
	for (String prefix : prefixes) {
	final String p = prefix;
	File[] match = searchRoot.listFiles((FileFilter) candidate -> {
	if (!candidate.isDirectory())
	return false;
	if (currentConfig.equals(candidate))
	return false;
	return candidate.getName().contains(p);
	});
	if (match.length != 0)
	return new ConfigurationDescriptor("unknown", new Identifier("0.0.0"), "unknown", "unknown", match[0]); //$NON-NLS-1$//$NON-NLS-2$//$NON-NLS-3$//$NON-NLS-4$
	}
	return null;
	}

	private ConfigurationDescriptor getConfigdataFromProductFile(File installFolder) {
	Object[] productFileInfo = loadEclipseProductFile(installFolder);
	// Contrarily to the runtime, when the .eclipseproduct can't be found, we don't
	// fallback to org.eclipse.platform.
	if (productFileInfo.length == 0)
	return null;
	return new ConfigurationDescriptor((String) productFileInfo[0], (Identifier) productFileInfo[1],
	getInstallDirHash(installFolder),
	Platform.getOS() + '_' + Platform.getWS() + '_' + Platform.getOSArch(), null);
	}

	public ConfigurationDescriptor findMostRelevantConfigurationFromInstallHashDir(
	List<ConfigurationDescriptor> configurations, ConfigurationDescriptor configToMatch) {
	ConfigurationDescriptor bestMatch = null;
	int numberOfcriteriaMet = 0;
	for (ConfigurationDescriptor candidate : configurations) {
	int criteriaMet = 0;
	if (!candidate.getInstallPathHashcode().equals(configToMatch.getInstallPathHashcode())) {
	continue;
	}
	criteriaMet++;

	if (configToMatch.getProductId().equals(candidate.getProductId()) && //
	configToMatch.getPlatformConfig().equals(candidate.getPlatformConfig()) && //
	(!candidate.getVersion().isGreaterEqualTo(configToMatch.getVersion()))) {
	// We have a match
	criteriaMet++;
	}

	if (criteriaMet == 0)
	continue;
	if (criteriaMet > numberOfcriteriaMet) {
	bestMatch = candidate;
	numberOfcriteriaMet = criteriaMet;
	} else if (criteriaMet == numberOfcriteriaMet) {
	if (bestMatch.getVersion().equals(candidate.getVersion())) {
	if (bestMatch.getConfig().lastModified() < candidate.getConfig().lastModified()) {
	bestMatch = candidate;
	}
	} else {
	if (candidate.getVersion().isGreaterEqualTo(bestMatch.getVersion()))
	bestMatch = candidate;
	}
	}
	}
	return bestMatch;
	}

	// Out of a set of configuration, find the one with the most similar product
	// info.
	public ConfigurationDescriptor findMostRelevantConfigurationFromProductId(
	List<ConfigurationDescriptor> configurations, ConfigurationDescriptor configToMatch) {
	ConfigurationDescriptor bestMatch = null;

	List<ConfigurationDescriptor> candidates = new ArrayList<>();
	List<ConfigurationDescriptor> candidatesWithUnkonwArchitecture = new ArrayList<>();
	for (ConfigurationDescriptor candidate : configurations) {
	if (configToMatch.getProductId().equals(candidate.getProductId())
	&& configToMatch.getVersion().isGreaterEqualTo(candidate.getVersion())) {
	if (configToMatch.getPlatformConfig().equals(candidate.getPlatformConfig())) {
	candidates.add(candidate);
	} else { // candidate.getPlatformConfig() returns null in legacy installation prior to
	// 4.x.x releases
	candidatesWithUnkonwArchitecture.add(candidate);
	}
	}
	}

	if (!candidates.isEmpty()) {
	candidates.sort(new ConfigurationDescriptorComparator());
	bestMatch = candidates.get(candidates.size() - 1);
	}

	if (bestMatch == null) {
	if (!candidatesWithUnkonwArchitecture.isEmpty()) {
	candidatesWithUnkonwArchitecture.sort(new ConfigurationDescriptorComparator());
	bestMatch = candidatesWithUnkonwArchitecture.get(candidatesWithUnkonwArchitecture.size() - 1);
	}
	}

	return bestMatch;
	}

	// Load the .eclipseproduct file in the base of the installation. This logic is
	// very similar to the one found in the launcher
	private Object[] loadEclipseProductFile(File installDir) {
	final String ECLIPSE = "eclipse"; //$NON-NLS-1$
	final String PRODUCT_SITE_MARKER = ".eclipseproduct"; //$NON-NLS-1$
	final String PRODUCT_SITE_ID = "id"; //$NON-NLS-1$
	final String PRODUCT_SITE_VERSION = "version"; //$NON-NLS-1$

	File eclipseProduct = new File(installDir, PRODUCT_SITE_MARKER);
	String appId = null;
	Identifier appVersion = null;
	if (eclipseProduct.exists()) {
	Properties props = new Properties();
	try (FileInputStream is = new FileInputStream(eclipseProduct)) {
	props.load(is);
	appId = props.getProperty(PRODUCT_SITE_ID);
	if (appId == null \|\| appId.trim().length() == 0)
	appId = ECLIPSE;
	String version = props.getProperty(PRODUCT_SITE_VERSION);
	if (version == null \|\| version.trim().length() == 0)
	appVersion = new Identifier(0, 0, 0);
	else
	appVersion = new Identifier(version);
	} catch (IOException e) {
	return new String[0];
	}
	} else {
	return new String[0];
	}
	return new Object[] { appId, appVersion };
	}

	// Iterate through a folder to look for potential configuration folders and
	// reify them.
	public List<ConfigurationDescriptor> readPreviousConfigurations(File configurationFolder) {
	File[] candidates = configurationFolder.listFiles();
	List<ConfigurationDescriptor> configurations = new ArrayList<>(candidates.length);
	for (File candidate : candidates) {
	if (!candidate.isDirectory())
	continue;
	if (candidate.equals(currentConfig))
	continue;
	ConfigurationDescriptor tmp = extractConfigurationData(candidate);
	if (tmp != null)
	configurations.add(tmp);
	}
	return configurations;
	}

	// This code computes the hashCode of the install location.
	// This is a simplified version of the code that the launcher executes.
	private String getInstallDirHash(File installFolder) {
	try {
	return Integer.toString(installFolder.getCanonicalPath().hashCode());
	} catch (IOException e) {
	return ""; //$NON-NLS-1$
	}
	}
	}