Copyright (c) 2006, 2013 IBM Corporation 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:
    IBM Corporation - initial API and implementation
    Bjorn Freeman-Benson - initial API and implementation
/*******************************************************************************
 * Copyright (c) 2006, 2013 IBM Corporation 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:
 *     IBM Corporation - initial API and implementation
 *     Bjorn Freeman-Benson - initial API and implementation
 *******************************************************************************/
package org.eclipse.core.internal.variables;

import java.net.URL;

import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IPath;
import org.eclipse.core.runtime.Path;
import org.eclipse.core.runtime.Platform;
import org.eclipse.core.variables.IDynamicVariable;
import org.eclipse.core.variables.IDynamicVariableResolver;
import org.eclipse.osgi.service.datalocation.Location;

Resolver for ${eclipse_home}
Since:
3.2/**
 * Resolver for ${eclipse_home}
 *
 * @since 3.2
 */
public class EclipseHomeVariableResolver implements IDynamicVariableResolver {

	@Override
	public String resolveValue(IDynamicVariable variable, String argument) throws CoreException {
		Location installLocation = Platform.getInstallLocation();
		if (installLocation != null) {
			URL url = installLocation.getURL();
			if (url != null) {

				// Try to convert the URL to an OS string, to be consistent with
				// how other variables, like ${workspace_loc} resolve. See
				// ResourceResolver.translateToValue(). [bugzilla 263535]
				String file = url.getFile();
				IPath path = Path.fromOSString(file);
				String osstr = path.toOSString();
				if (osstr.length() != 0) {
					return osstr;
				}

				if (file.length() != 0) {
					return file;
				}
			}
		}
		return null;
	}

}