bundles/org.eclipse.osgi/container/src/org/eclipse/osgi/internal/location/EquinoxLocations.java - equinox/rt.equinox.framework - Git at Google

 /*******************************************************************************
  * Copyright (c) 2004, 2015 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
  *     Rapicorp, Inc - Support for Mac Layout (bug 431116)
  *******************************************************************************/
 package org.eclipse.osgi.internal.location;

 import java.io.*;
 import java.net.MalformedURLException;
 import java.net.URL;
 import java.util.Properties;
 import org.eclipse.osgi.internal.framework.EquinoxConfiguration;
 import org.eclipse.osgi.service.datalocation.Location;
 import org.eclipse.osgi.storage.StorageUtil;
 import org.osgi.framework.Constants;

 /**
  * This class is used to manage the various Locations for Eclipse.
  */
 public class EquinoxLocations {
 	public static final String READ_ONLY_AREA_SUFFIX = ".readOnly"; //$NON-NLS-1$
 	public static final String PROP_INSTALL_AREA = "osgi.install.area"; //$NON-NLS-1$
 	public static final String PROP_CONFIG_AREA = "osgi.configuration.area"; //$NON-NLS-1$
 	public static final String PROP_CONFIG_AREA_DEFAULT = "osgi.configuration.area.default"; //$NON-NLS-1$
 	public static final String PROP_SHARED_CONFIG_AREA = "osgi.sharedConfiguration.area"; //$NON-NLS-1$
 	public static final String PROP_INSTANCE_AREA = "osgi.instance.area"; //$NON-NLS-1$
 	public static final String PROP_INSTANCE_AREA_DEFAULT = "osgi.instance.area.default"; //$NON-NLS-1$
 	public static final String PROP_USER_AREA = "osgi.user.area"; //$NON-NLS-1$
 	public static final String PROP_USER_AREA_DEFAULT = "osgi.user.area.default"; //$NON-NLS-1$
 	public static final String PROP_USER_HOME = "user.home"; //$NON-NLS-1$
 	public static final String PROP_USER_DIR = "user.dir"; //$NON-NLS-1$
 	public static final String PROP_HOME_LOCATION_AREA = "eclipse.home.location"; //$NON-NLS-1$
 	public static final String PROP_LAUNCHER = "eclipse.launcher"; //$NON-NLS-1$

 	// Constants for configuration location discovery
 	private static final String ECLIPSE = "eclipse"; //$NON-NLS-1$
 	private static final String PRODUCT_SITE_MARKER = ".eclipseproduct"; //$NON-NLS-1$
 	private static final String PRODUCT_SITE_ID = "id"; //$NON-NLS-1$
 	private static final String PRODUCT_SITE_VERSION = "version"; //$NON-NLS-1$

 	private static final String CONFIG_DIR = "configuration"; //$NON-NLS-1$

 	// Data mode constants for user, configuration and data locations.
 	private static final String NONE = "@none"; //$NON-NLS-1$
 	private static final String NO_DEFAULT = "@noDefault"; //$NON-NLS-1$
 	private static final String USER_HOME = "@user.home"; //$NON-NLS-1$
 	private static final String USER_DIR = "@user.dir"; //$NON-NLS-1$
 	// Placeholder for hashcode of installation directory
 	private static final String INSTALL_HASH_PLACEHOLDER = "@install.hash"; //$NON-NLS-1$

 	private static final String INSTANCE_DATA_AREA_PREFIX = ".metadata/.plugins/"; //$NON-NLS-1$

 	private final EquinoxConfiguration equinoxConfig;

 	private final Location installLocation;
 	private final Location configurationLocation;
 	private final Location userLocation;
 	private final Location instanceLocation;
 	private final Location eclipseHomeLocation;

 	public EquinoxLocations(EquinoxConfiguration equinoxConfig) {
 		this.equinoxConfig = equinoxConfig;

 		// Initializes the Location objects for the LocationManager.
 		// set the osgi storage area if it exists
 		String osgiStorage = equinoxConfig.getConfiguration(Constants.FRAMEWORK_STORAGE);
 		if (osgiStorage != null)
 			equinoxConfig.setConfiguration(PROP_CONFIG_AREA, osgiStorage);
 		// do install location initialization first since others may depend on it
 		// assumes that the property is already set
 		installLocation = buildLocation(PROP_INSTALL_AREA, null, "", true, false, null); //$NON-NLS-1$

 		// TODO not sure what the data area prefix should be here for the user area
 		Location temp = buildLocation(PROP_USER_AREA_DEFAULT, null, "", false, false, null); //$NON-NLS-1$
 		URL defaultLocation = temp == null ? null : temp.getURL();
 		if (defaultLocation == null)
 			defaultLocation = buildURL(new File(System.getProperty(PROP_USER_HOME), "user").getAbsolutePath(), true); //$NON-NLS-1$
 		userLocation = buildLocation(PROP_USER_AREA, defaultLocation, "", false, false, null); //$NON-NLS-1$

 		temp = buildLocation(PROP_INSTANCE_AREA_DEFAULT, null, "", false, false, INSTANCE_DATA_AREA_PREFIX); //$NON-NLS-1$
 		defaultLocation = temp == null ? null : temp.getURL();
 		if (defaultLocation == null)
 			defaultLocation = buildURL(new File(System.getProperty(PROP_USER_DIR), "workspace").getAbsolutePath(), true); //$NON-NLS-1$
 		instanceLocation = buildLocation(PROP_INSTANCE_AREA, defaultLocation, "", false, false, INSTANCE_DATA_AREA_PREFIX); //$NON-NLS-1$

 		mungeConfigurationLocation();
 		// compute a default but it is very unlikely to be used since main will have computed everything
 		temp = buildLocation(PROP_CONFIG_AREA_DEFAULT, null, "", false, false, null); //$NON-NLS-1$
 		defaultLocation = temp == null ? null : temp.getURL();
 		if (defaultLocation == null && equinoxConfig.getConfiguration(PROP_CONFIG_AREA) == null)
 			// only compute the default if the configuration area property is not set
 			defaultLocation = buildURL(computeDefaultConfigurationLocation(), true);
 		configurationLocation = buildLocation(PROP_CONFIG_AREA, defaultLocation, "", false, false, null); //$NON-NLS-1$
 		// get the parent location based on the system property. This will have been set on the
 		// way in either by the caller/user or by main.  There will be no parent location if we are not
 		// cascaded.
 		URL parentLocation = computeSharedConfigurationLocation();
 		if (parentLocation != null && !parentLocation.equals(configurationLocation.getURL())) {
 			Location parent = new BasicLocation(null, parentLocation, true, null, equinoxConfig);
 			((BasicLocation) configurationLocation).setParent(parent);
 		}

 		if (equinoxConfig.getConfiguration(PROP_HOME_LOCATION_AREA) == null) {
 			String eclipseLauncher = equinoxConfig.getConfiguration(PROP_LAUNCHER);
 			String eclipseHomeLocationPath = getEclipseHomeLocation(eclipseLauncher, equinoxConfig);
 			if (eclipseHomeLocationPath != null)
 				equinoxConfig.setConfiguration(PROP_HOME_LOCATION_AREA, eclipseHomeLocationPath);
 		}
 		// if eclipse.home.location is not set then default to osgi.install.area
 		if (equinoxConfig.getConfiguration(PROP_HOME_LOCATION_AREA) == null && equinoxConfig.getConfiguration(PROP_INSTALL_AREA) != null)
 			equinoxConfig.setConfiguration(PROP_HOME_LOCATION_AREA, equinoxConfig.getConfiguration(PROP_INSTALL_AREA));
 		eclipseHomeLocation = buildLocation(PROP_HOME_LOCATION_AREA, null, "", true, true, null); //$NON-NLS-1$
 	}

 	/**
 	 * Builds a URL with the given specification
 	 * @param spec the URL specification
 	 * @param trailingSlash flag to indicate a trailing slash on the spec
 	 * @return a URL
 	 */
 	public static URL buildURL(String spec, boolean trailingSlash) {
 		return LocationHelper.buildURL(spec, trailingSlash);
 	}

 	private void mungeConfigurationLocation() {
 		// if the config property was set, munge it for backwards compatibility.
 		String location = equinoxConfig.getConfiguration(PROP_CONFIG_AREA);
 		if (location != null) {
 			if (location.endsWith(".cfg")) { //$NON-NLS-1$
 				int index = location.lastIndexOf('/');
 				if (index < 0)
 					index = location.lastIndexOf('\\');
 				location = location.substring(0, index + 1);
 				equinoxConfig.setConfiguration(PROP_CONFIG_AREA, location);
 			}
 		}
 	}

 	private static String getEclipseHomeLocation(String launcher, EquinoxConfiguration equinoxConfig) {
 		if (launcher == null)
 			return null;
 		File launcherFile = new File(launcher);
 		if (launcherFile.getParent() == null)
 			return null;
 		File launcherDir = new File(launcherFile.getParent());
 		// check for mac os; the os check is copied from EclipseEnvironmentInfo.
 		String macosx = org.eclipse.osgi.service.environment.Constants.OS_MACOSX;
 		if (macosx.equals(equinoxConfig.getOS()))
 			launcherDir = getMacOSEclipseHomeLocation(launcherDir);
 		return (launcherDir.exists() && launcherDir.isDirectory()) ? launcherDir.getAbsolutePath() : null;
 	}

 	private static File getMacOSEclipseHomeLocation(File launcherDir) {
 		if (!launcherDir.getName().equalsIgnoreCase("macos")) //$NON-NLS-1$
 			return launcherDir; // don't do the up three stuff if not in macos directory
 		return new File(launcherDir.getParent(), "Eclipse"); //$NON-NLS-1$
 	}

 	@SuppressWarnings("deprecation")
 	private Location buildLocation(String property, URL defaultLocation, String userDefaultAppendage, boolean readOnlyDefault, boolean computeReadOnly, String dataAreaPrefix) {
 		String location = equinoxConfig.clearConfiguration(property);
 		// the user/product may specify a non-default readOnly setting
 		String userReadOnlySetting = equinoxConfig.getConfiguration(property + READ_ONLY_AREA_SUFFIX);
 		boolean readOnly = (userReadOnlySetting == null ? readOnlyDefault : Boolean.valueOf(userReadOnlySetting).booleanValue());
 		// if the instance location is not set, predict where the workspace will be and
 		// put the instance area inside the workspace meta area.
 		if (location == null)
 			return new BasicLocation(property, defaultLocation, userReadOnlySetting != null || !computeReadOnly ? readOnly : !canWrite(defaultLocation), dataAreaPrefix, equinoxConfig);
 		String trimmedLocation = location.trim();
 		if (trimmedLocation.equalsIgnoreCase(NONE))
 			return null;
 		if (trimmedLocation.equalsIgnoreCase(NO_DEFAULT))
 			return new BasicLocation(property, null, readOnly, dataAreaPrefix, equinoxConfig);
 		if (trimmedLocation.startsWith(USER_HOME)) {
 			String base = substituteVar(location, USER_HOME, PROP_USER_HOME);
 			location = new File(base, userDefaultAppendage).getAbsolutePath();
 		} else if (trimmedLocation.startsWith(USER_DIR)) {
 			String base = substituteVar(location, USER_DIR, PROP_USER_DIR);
 			location = new File(base, userDefaultAppendage).getAbsolutePath();
 		}
 		int idx = location.indexOf(INSTALL_HASH_PLACEHOLDER);
 		if (idx == 0) {
 			throw new RuntimeException("The location cannot start with '" + INSTALL_HASH_PLACEHOLDER + "': " + location); //$NON-NLS-1$ //$NON-NLS-2$
 		} else if (idx > 0) {
 			location = location.substring(0, idx) + getInstallDirHash() + location.substring(idx + INSTALL_HASH_PLACEHOLDER.length());
 		}
 		URL url = buildURL(location, true);
 		BasicLocation result = null;
 		if (url != null) {
 			result = new BasicLocation(property, null, userReadOnlySetting != null || !computeReadOnly ? readOnly : !canWrite(url), dataAreaPrefix, equinoxConfig);
 			result.setURL(url, false);
 		}
 		return result;
 	}

 	private String substituteVar(String source, String var, String prop) {
 		String value = equinoxConfig.getConfiguration(prop, ""); //$NON-NLS-1$
 		return value + source.substring(var.length());
 	}

 	private URL computeInstallConfigurationLocation() {
 		String property = equinoxConfig.getConfiguration(PROP_INSTALL_AREA);
 		if (property != null)
 			return LocationHelper.buildURL(property, true);
 		return null;
 	}

 	private URL computeSharedConfigurationLocation() {
 		String property = equinoxConfig.getConfiguration(PROP_SHARED_CONFIG_AREA);
 		if (property == null)
 			return null;
 		try {
 			URL sharedConfigurationURL = LocationHelper.buildURL(property, true);
 			if (sharedConfigurationURL == null)
 				return null;
 			if (sharedConfigurationURL.getPath().startsWith("/")) //$NON-NLS-1$
 				// absolute
 				return sharedConfigurationURL;
 			URL installURL = installLocation.getURL();
 			if (!sharedConfigurationURL.getProtocol().equals(installURL.getProtocol()))
 				// different protocol
 				return sharedConfigurationURL;
 			sharedConfigurationURL = new URL(installURL, sharedConfigurationURL.getPath());
 			equinoxConfig.setConfiguration(PROP_SHARED_CONFIG_AREA, sharedConfigurationURL.toExternalForm());
 		} catch (MalformedURLException e) {
 			// do nothing here since it is basically impossible to get a bogus url
 		}
 		return null;
 	}

 	private String computeDefaultConfigurationLocation() {
 		// 1) We store the config state relative to the 'eclipse' directory if possible
 		// 2) If this directory is read-only
 		//    we store the state in <user.home>/.eclipse/<application-id>_<version> where <user.home>
 		//    is unique for each local user, and <application-id> is the one
 		//    defined in .eclipseproduct marker file. If .eclipseproduct does not
 		//    exist, use "eclipse" as the application-id.

 		URL installURL = computeInstallConfigurationLocation();
 		if (installURL != null && "file".equals(installURL.getProtocol())) { //$NON-NLS-1$
 			File installDir = new File(installURL.getFile());
 			File defaultConfigDir = new File(installDir, CONFIG_DIR);
 			if (!defaultConfigDir.exists())
 				defaultConfigDir.mkdirs();
 			if (defaultConfigDir.exists() && StorageUtil.canWrite(defaultConfigDir))
 				return defaultConfigDir.getAbsolutePath();
 		}
 		// We can't write in the eclipse install dir so try for some place in the user's home dir
 		return computeDefaultUserAreaLocation(CONFIG_DIR);
 	}

 	private static boolean canWrite(URL location) {
 		if (location != null && "file".equals(location.getProtocol())) { //$NON-NLS-1$
 			File locationDir = new File(location.getFile());
 			if (!locationDir.exists())
 				locationDir.mkdirs();
 			if (locationDir.exists() && StorageUtil.canWrite(locationDir))
 				return true;
 		}
 		return false;
 	}

 	private String computeDefaultUserAreaLocation(String pathAppendage) {
 		//    we store the state in <user.home>/.eclipse/<application-id>_<version> where <user.home>
 		//    is unique for each local user, and <application-id> is the one
 		//    defined in .eclipseproduct marker file. If .eclipseproduct does not
 		//    exist, use "eclipse" as the application-id.
 		String installProperty = equinoxConfig.getConfiguration(PROP_INSTALL_AREA);
 		URL installURL = buildURL(installProperty, true);
 		if (installURL == null)
 			return null;
 		File installDir = new File(installURL.getFile());
 		String installDirHash = getInstallDirHash();

 		String appName = "." + ECLIPSE; //$NON-NLS-1$
 		File eclipseProduct = new File(installDir, PRODUCT_SITE_MARKER);
 		if (eclipseProduct.exists()) {
 			Properties props = new Properties();
 			try {
 				props.load(new FileInputStream(eclipseProduct));
 				String appId = props.getProperty(PRODUCT_SITE_ID);
 				if (appId == null || appId.trim().length() == 0)
 					appId = ECLIPSE;
 				String appVersion = props.getProperty(PRODUCT_SITE_VERSION);
 				if (appVersion == null || appVersion.trim().length() == 0)
 					appVersion = ""; //$NON-NLS-1$
 				appName += File.separator + appId + "_" + appVersion + "_" + installDirHash; //$NON-NLS-1$ //$NON-NLS-2$
 			} catch (IOException e) {
 				// Do nothing if we get an exception.  We will default to a standard location
 				// in the user's home dir.
 				// add the hash to help prevent collisions
 				appName += File.separator + installDirHash;
 			}
 		} else {
 			// add the hash to help prevent collisions
 			appName += File.separator + installDirHash;
 		}
 		String userHome = System.getProperty(PROP_USER_HOME);
 		return new File(userHome, appName + "/" + pathAppendage).getAbsolutePath(); //$NON-NLS-1$
 	}

 	/**
 	 * Return hash code identifying an absolute installation path
 	 * @return hash code as String
 	 */
 	private String getInstallDirHash() {
 		// compute an install dir hash to prevent configuration area collisions with other eclipse installs
 		String installProperty = equinoxConfig.getConfiguration(PROP_INSTALL_AREA);
 		URL installURL = buildURL(installProperty, true);
 		if (installURL == null)
 			return ""; //$NON-NLS-1$
 		File installDir = new File(installURL.getFile());
 		int hashCode;
 		try {
 			hashCode = installDir.getCanonicalPath().hashCode();
 		} catch (IOException ioe) {
 			// fall back to absolute path
 			hashCode = installDir.getAbsolutePath().hashCode();
 		}
 		if (hashCode < 0)
 			hashCode = -(hashCode);
 		String installDirHash = String.valueOf(hashCode);
 		return installDirHash;
 	}

 	/**
 	 * Returns the user Location object
 	 * @return the user Location object
 	 */
 	public Location getUserLocation() {
 		return userLocation;
 	}

 	/**
 	 * Returns the configuration Location object
 	 * @return the configuration Location object
 	 */
 	public Location getConfigurationLocation() {
 		return configurationLocation;
 	}

 	/**
 	 * Returns the install Location object
 	 * @return the install Location object
 	 */
 	public Location getInstallLocation() {
 		return installLocation;
 	}

 	/**
 	 * Returns the instance Location object
 	 * @return the instance Location object
 	 */
 	public Location getInstanceLocation() {
 		return instanceLocation;
 	}

 	public Location getEclipseHomeLocation() {
 		return eclipseHomeLocation;
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2004, 2015 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
	* Rapicorp, Inc - Support for Mac Layout (bug 431116)
	*******************************************************************************/
	package org.eclipse.osgi.internal.location;

	import java.io.*;
	import java.net.MalformedURLException;
	import java.net.URL;
	import java.util.Properties;
	import org.eclipse.osgi.internal.framework.EquinoxConfiguration;
	import org.eclipse.osgi.service.datalocation.Location;
	import org.eclipse.osgi.storage.StorageUtil;
	import org.osgi.framework.Constants;

	/**
	* This class is used to manage the various Locations for Eclipse.
	*/
	public class EquinoxLocations {
	public static final String READ_ONLY_AREA_SUFFIX = ".readOnly"; //$NON-NLS-1$
	public static final String PROP_INSTALL_AREA = "osgi.install.area"; //$NON-NLS-1$
	public static final String PROP_CONFIG_AREA = "osgi.configuration.area"; //$NON-NLS-1$
	public static final String PROP_CONFIG_AREA_DEFAULT = "osgi.configuration.area.default"; //$NON-NLS-1$
	public static final String PROP_SHARED_CONFIG_AREA = "osgi.sharedConfiguration.area"; //$NON-NLS-1$
	public static final String PROP_INSTANCE_AREA = "osgi.instance.area"; //$NON-NLS-1$
	public static final String PROP_INSTANCE_AREA_DEFAULT = "osgi.instance.area.default"; //$NON-NLS-1$
	public static final String PROP_USER_AREA = "osgi.user.area"; //$NON-NLS-1$
	public static final String PROP_USER_AREA_DEFAULT = "osgi.user.area.default"; //$NON-NLS-1$
	public static final String PROP_USER_HOME = "user.home"; //$NON-NLS-1$
	public static final String PROP_USER_DIR = "user.dir"; //$NON-NLS-1$
	public static final String PROP_HOME_LOCATION_AREA = "eclipse.home.location"; //$NON-NLS-1$
	public static final String PROP_LAUNCHER = "eclipse.launcher"; //$NON-NLS-1$

	// Constants for configuration location discovery
	private static final String ECLIPSE = "eclipse"; //$NON-NLS-1$
	private static final String PRODUCT_SITE_MARKER = ".eclipseproduct"; //$NON-NLS-1$
	private static final String PRODUCT_SITE_ID = "id"; //$NON-NLS-1$
	private static final String PRODUCT_SITE_VERSION = "version"; //$NON-NLS-1$

	private static final String CONFIG_DIR = "configuration"; //$NON-NLS-1$

	// Data mode constants for user, configuration and data locations.
	private static final String NONE = "@none"; //$NON-NLS-1$
	private static final String NO_DEFAULT = "@noDefault"; //$NON-NLS-1$
	private static final String USER_HOME = "@user.home"; //$NON-NLS-1$
	private static final String USER_DIR = "@user.dir"; //$NON-NLS-1$
	// Placeholder for hashcode of installation directory
	private static final String INSTALL_HASH_PLACEHOLDER = "@install.hash"; //$NON-NLS-1$

	private static final String INSTANCE_DATA_AREA_PREFIX = ".metadata/.plugins/"; //$NON-NLS-1$

	private final EquinoxConfiguration equinoxConfig;

	private final Location installLocation;
	private final Location configurationLocation;
	private final Location userLocation;
	private final Location instanceLocation;
	private final Location eclipseHomeLocation;

	public EquinoxLocations(EquinoxConfiguration equinoxConfig) {
	this.equinoxConfig = equinoxConfig;

	// Initializes the Location objects for the LocationManager.
	// set the osgi storage area if it exists
	String osgiStorage = equinoxConfig.getConfiguration(Constants.FRAMEWORK_STORAGE);
	if (osgiStorage != null)
	equinoxConfig.setConfiguration(PROP_CONFIG_AREA, osgiStorage);
	// do install location initialization first since others may depend on it
	// assumes that the property is already set
	installLocation = buildLocation(PROP_INSTALL_AREA, null, "", true, false, null); //$NON-NLS-1$

	// TODO not sure what the data area prefix should be here for the user area
	Location temp = buildLocation(PROP_USER_AREA_DEFAULT, null, "", false, false, null); //$NON-NLS-1$
	URL defaultLocation = temp == null ? null : temp.getURL();
	if (defaultLocation == null)
	defaultLocation = buildURL(new File(System.getProperty(PROP_USER_HOME), "user").getAbsolutePath(), true); //$NON-NLS-1$
	userLocation = buildLocation(PROP_USER_AREA, defaultLocation, "", false, false, null); //$NON-NLS-1$

	temp = buildLocation(PROP_INSTANCE_AREA_DEFAULT, null, "", false, false, INSTANCE_DATA_AREA_PREFIX); //$NON-NLS-1$
	defaultLocation = temp == null ? null : temp.getURL();
	if (defaultLocation == null)
	defaultLocation = buildURL(new File(System.getProperty(PROP_USER_DIR), "workspace").getAbsolutePath(), true); //$NON-NLS-1$
	instanceLocation = buildLocation(PROP_INSTANCE_AREA, defaultLocation, "", false, false, INSTANCE_DATA_AREA_PREFIX); //$NON-NLS-1$

	mungeConfigurationLocation();
	// compute a default but it is very unlikely to be used since main will have computed everything
	temp = buildLocation(PROP_CONFIG_AREA_DEFAULT, null, "", false, false, null); //$NON-NLS-1$
	defaultLocation = temp == null ? null : temp.getURL();
	if (defaultLocation == null && equinoxConfig.getConfiguration(PROP_CONFIG_AREA) == null)
	// only compute the default if the configuration area property is not set
	defaultLocation = buildURL(computeDefaultConfigurationLocation(), true);
	configurationLocation = buildLocation(PROP_CONFIG_AREA, defaultLocation, "", false, false, null); //$NON-NLS-1$
	// get the parent location based on the system property. This will have been set on the
	// way in either by the caller/user or by main. There will be no parent location if we are not
	// cascaded.
	URL parentLocation = computeSharedConfigurationLocation();
	if (parentLocation != null && !parentLocation.equals(configurationLocation.getURL())) {
	Location parent = new BasicLocation(null, parentLocation, true, null, equinoxConfig);
	((BasicLocation) configurationLocation).setParent(parent);
	}

	if (equinoxConfig.getConfiguration(PROP_HOME_LOCATION_AREA) == null) {
	String eclipseLauncher = equinoxConfig.getConfiguration(PROP_LAUNCHER);
	String eclipseHomeLocationPath = getEclipseHomeLocation(eclipseLauncher, equinoxConfig);
	if (eclipseHomeLocationPath != null)
	equinoxConfig.setConfiguration(PROP_HOME_LOCATION_AREA, eclipseHomeLocationPath);
	}
	// if eclipse.home.location is not set then default to osgi.install.area
	if (equinoxConfig.getConfiguration(PROP_HOME_LOCATION_AREA) == null && equinoxConfig.getConfiguration(PROP_INSTALL_AREA) != null)
	equinoxConfig.setConfiguration(PROP_HOME_LOCATION_AREA, equinoxConfig.getConfiguration(PROP_INSTALL_AREA));
	eclipseHomeLocation = buildLocation(PROP_HOME_LOCATION_AREA, null, "", true, true, null); //$NON-NLS-1$
	}

	/**
	* Builds a URL with the given specification
	* @param spec the URL specification
	* @param trailingSlash flag to indicate a trailing slash on the spec
	* @return a URL
	*/
	public static URL buildURL(String spec, boolean trailingSlash) {
	return LocationHelper.buildURL(spec, trailingSlash);
	}

	private void mungeConfigurationLocation() {
	// if the config property was set, munge it for backwards compatibility.
	String location = equinoxConfig.getConfiguration(PROP_CONFIG_AREA);
	if (location != null) {
	if (location.endsWith(".cfg")) { //$NON-NLS-1$
	int index = location.lastIndexOf('/');
	if (index < 0)
	index = location.lastIndexOf('\\');
	location = location.substring(0, index + 1);
	equinoxConfig.setConfiguration(PROP_CONFIG_AREA, location);
	}
	}
	}

	private static String getEclipseHomeLocation(String launcher, EquinoxConfiguration equinoxConfig) {
	if (launcher == null)
	return null;
	File launcherFile = new File(launcher);
	if (launcherFile.getParent() == null)
	return null;
	File launcherDir = new File(launcherFile.getParent());
	// check for mac os; the os check is copied from EclipseEnvironmentInfo.
	String macosx = org.eclipse.osgi.service.environment.Constants.OS_MACOSX;
	if (macosx.equals(equinoxConfig.getOS()))
	launcherDir = getMacOSEclipseHomeLocation(launcherDir);
	return (launcherDir.exists() && launcherDir.isDirectory()) ? launcherDir.getAbsolutePath() : null;
	}

	private static File getMacOSEclipseHomeLocation(File launcherDir) {
	if (!launcherDir.getName().equalsIgnoreCase("macos")) //$NON-NLS-1$
	return launcherDir; // don't do the up three stuff if not in macos directory
	return new File(launcherDir.getParent(), "Eclipse"); //$NON-NLS-1$
	}

	@SuppressWarnings("deprecation")
	private Location buildLocation(String property, URL defaultLocation, String userDefaultAppendage, boolean readOnlyDefault, boolean computeReadOnly, String dataAreaPrefix) {
	String location = equinoxConfig.clearConfiguration(property);
	// the user/product may specify a non-default readOnly setting
	String userReadOnlySetting = equinoxConfig.getConfiguration(property + READ_ONLY_AREA_SUFFIX);
	boolean readOnly = (userReadOnlySetting == null ? readOnlyDefault : Boolean.valueOf(userReadOnlySetting).booleanValue());
	// if the instance location is not set, predict where the workspace will be and
	// put the instance area inside the workspace meta area.
	if (location == null)
	return new BasicLocation(property, defaultLocation, userReadOnlySetting != null \|\| !computeReadOnly ? readOnly : !canWrite(defaultLocation), dataAreaPrefix, equinoxConfig);
	String trimmedLocation = location.trim();
	if (trimmedLocation.equalsIgnoreCase(NONE))
	return null;
	if (trimmedLocation.equalsIgnoreCase(NO_DEFAULT))
	return new BasicLocation(property, null, readOnly, dataAreaPrefix, equinoxConfig);
	if (trimmedLocation.startsWith(USER_HOME)) {
	String base = substituteVar(location, USER_HOME, PROP_USER_HOME);
	location = new File(base, userDefaultAppendage).getAbsolutePath();
	} else if (trimmedLocation.startsWith(USER_DIR)) {
	String base = substituteVar(location, USER_DIR, PROP_USER_DIR);
	location = new File(base, userDefaultAppendage).getAbsolutePath();
	}
	int idx = location.indexOf(INSTALL_HASH_PLACEHOLDER);
	if (idx == 0) {
	throw new RuntimeException("The location cannot start with '" + INSTALL_HASH_PLACEHOLDER + "': " + location); //$NON-NLS-1$ //$NON-NLS-2$
	} else if (idx > 0) {
	location = location.substring(0, idx) + getInstallDirHash() + location.substring(idx + INSTALL_HASH_PLACEHOLDER.length());
	}
	URL url = buildURL(location, true);
	BasicLocation result = null;
	if (url != null) {
	result = new BasicLocation(property, null, userReadOnlySetting != null \|\| !computeReadOnly ? readOnly : !canWrite(url), dataAreaPrefix, equinoxConfig);
	result.setURL(url, false);
	}
	return result;
	}

	private String substituteVar(String source, String var, String prop) {
	String value = equinoxConfig.getConfiguration(prop, ""); //$NON-NLS-1$
	return value + source.substring(var.length());
	}

	private URL computeInstallConfigurationLocation() {
	String property = equinoxConfig.getConfiguration(PROP_INSTALL_AREA);
	if (property != null)
	return LocationHelper.buildURL(property, true);
	return null;
	}

	private URL computeSharedConfigurationLocation() {
	String property = equinoxConfig.getConfiguration(PROP_SHARED_CONFIG_AREA);
	if (property == null)
	return null;
	try {
	URL sharedConfigurationURL = LocationHelper.buildURL(property, true);
	if (sharedConfigurationURL == null)
	return null;
	if (sharedConfigurationURL.getPath().startsWith("/")) //$NON-NLS-1$
	// absolute
	return sharedConfigurationURL;
	URL installURL = installLocation.getURL();
	if (!sharedConfigurationURL.getProtocol().equals(installURL.getProtocol()))
	// different protocol
	return sharedConfigurationURL;
	sharedConfigurationURL = new URL(installURL, sharedConfigurationURL.getPath());
	equinoxConfig.setConfiguration(PROP_SHARED_CONFIG_AREA, sharedConfigurationURL.toExternalForm());
	} catch (MalformedURLException e) {
	// do nothing here since it is basically impossible to get a bogus url
	}
	return null;
	}

	private String computeDefaultConfigurationLocation() {
	// 1) We store the config state relative to the 'eclipse' directory if possible
	// 2) If this directory is read-only
	// we store the state in <user.home>/.eclipse/<application-id>_<version> where <user.home>
	// is unique for each local user, and <application-id> is the one
	// defined in .eclipseproduct marker file. If .eclipseproduct does not
	// exist, use "eclipse" as the application-id.

	URL installURL = computeInstallConfigurationLocation();
	if (installURL != null && "file".equals(installURL.getProtocol())) { //$NON-NLS-1$
	File installDir = new File(installURL.getFile());
	File defaultConfigDir = new File(installDir, CONFIG_DIR);
	if (!defaultConfigDir.exists())
	defaultConfigDir.mkdirs();
	if (defaultConfigDir.exists() && StorageUtil.canWrite(defaultConfigDir))
	return defaultConfigDir.getAbsolutePath();
	}
	// We can't write in the eclipse install dir so try for some place in the user's home dir
	return computeDefaultUserAreaLocation(CONFIG_DIR);
	}

	private static boolean canWrite(URL location) {
	if (location != null && "file".equals(location.getProtocol())) { //$NON-NLS-1$
	File locationDir = new File(location.getFile());
	if (!locationDir.exists())
	locationDir.mkdirs();
	if (locationDir.exists() && StorageUtil.canWrite(locationDir))
	return true;
	}
	return false;
	}

	private String computeDefaultUserAreaLocation(String pathAppendage) {
	// we store the state in <user.home>/.eclipse/<application-id>_<version> where <user.home>
	// is unique for each local user, and <application-id> is the one
	// defined in .eclipseproduct marker file. If .eclipseproduct does not
	// exist, use "eclipse" as the application-id.
	String installProperty = equinoxConfig.getConfiguration(PROP_INSTALL_AREA);
	URL installURL = buildURL(installProperty, true);
	if (installURL == null)
	return null;
	File installDir = new File(installURL.getFile());
	String installDirHash = getInstallDirHash();

	String appName = "." + ECLIPSE; //$NON-NLS-1$
	File eclipseProduct = new File(installDir, PRODUCT_SITE_MARKER);
	if (eclipseProduct.exists()) {
	Properties props = new Properties();
	try {
	props.load(new FileInputStream(eclipseProduct));
	String appId = props.getProperty(PRODUCT_SITE_ID);
	if (appId == null \|\| appId.trim().length() == 0)
	appId = ECLIPSE;
	String appVersion = props.getProperty(PRODUCT_SITE_VERSION);
	if (appVersion == null \|\| appVersion.trim().length() == 0)
	appVersion = ""; //$NON-NLS-1$
	appName += File.separator + appId + "_" + appVersion + "_" + installDirHash; //$NON-NLS-1$ //$NON-NLS-2$
	} catch (IOException e) {
	// Do nothing if we get an exception. We will default to a standard location
	// in the user's home dir.
	// add the hash to help prevent collisions
	appName += File.separator + installDirHash;
	}
	} else {
	// add the hash to help prevent collisions
	appName += File.separator + installDirHash;
	}
	String userHome = System.getProperty(PROP_USER_HOME);
	return new File(userHome, appName + "/" + pathAppendage).getAbsolutePath(); //$NON-NLS-1$
	}

	/**
	* Return hash code identifying an absolute installation path
	* @return hash code as String
	*/
	private String getInstallDirHash() {
	// compute an install dir hash to prevent configuration area collisions with other eclipse installs
	String installProperty = equinoxConfig.getConfiguration(PROP_INSTALL_AREA);
	URL installURL = buildURL(installProperty, true);
	if (installURL == null)
	return ""; //$NON-NLS-1$
	File installDir = new File(installURL.getFile());
	int hashCode;
	try {
	hashCode = installDir.getCanonicalPath().hashCode();
	} catch (IOException ioe) {
	// fall back to absolute path
	hashCode = installDir.getAbsolutePath().hashCode();
	}
	if (hashCode < 0)
	hashCode = -(hashCode);
	String installDirHash = String.valueOf(hashCode);
	return installDirHash;
	}

	/**
	* Returns the user Location object
	* @return the user Location object
	*/
	public Location getUserLocation() {
	return userLocation;
	}

	/**
	* Returns the configuration Location object
	* @return the configuration Location object
	*/
	public Location getConfigurationLocation() {
	return configurationLocation;
	}

	/**
	* Returns the install Location object
	* @return the install Location object
	*/
	public Location getInstallLocation() {
	return installLocation;
	}

	/**
	* Returns the instance Location object
	* @return the instance Location object
	*/
	public Location getInstanceLocation() {
	return instanceLocation;
	}

	public Location getEclipseHomeLocation() {
	return eclipseHomeLocation;
	}
	}