PlatformResourceCodeLocator.java

/*******************************************************************************
 * Copyright (c) 2008 Olivier Moises
 *
 * 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:
 *   Olivier Moises- initial API and implementation
 *   Pavel Erofeev - refactored for parsing with regexps
 *                   locator for platform:/resource URIs
 *******************************************************************************/

package org.eclipse.wazaabi.locator.platform.resource.codelocators;

import java.io.IOException;
import java.io.InputStream;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.eclipse.emf.common.util.URI;
import org.eclipse.emf.ecore.resource.ResourceSet;
import org.eclipse.emf.ecore.resource.impl.ResourceSetImpl;
import org.eclipse.wazaabi.engine.edp.coderesolution.AbstractCodeDescriptor;
import org.eclipse.wazaabi.engine.edp.coderesolution.ICodeLocator;
import org.eclipse.wazaabi.locator.platform.resource.codedescriptors.ResourceCodeDescriptor;

public class PlatformResourceCodeLocator implements ICodeLocator {

	public static final String FACTORY_ID = PlatformResourceCodeLocator.class
			.getName();

	static private final String URI_PREFIX = "platform:/resource/"; //$NON-NLS-1$ 
	static private final String LANGUAGE = "java"; //$NON-NLS-1$

	private static final Pattern PATTERN = Pattern.compile(URI_PREFIX
			+ "([^/]+)/([^\\?]+)(\\?language=(\\w+))?"); //$NON-NLS-1$ 
	private static final int PATTERN_BUNDLE = 1;
	private static final int PATTERN_PATH = 2;
	private static final int PATTERN_LANGUAGE = 4;

	private final ResourceSet rset = new ResourceSetImpl();

	public AbstractCodeDescriptor resolveCodeDescriptor(String uri) {
		Matcher m = PATTERN.matcher(uri);
		if (m.matches())
			return new ResourceCodeDescriptor(m.group(PATTERN_BUNDLE),
					m.group(PATTERN_PATH));
		return null;
	}

	public InputStream getResourceInputStream(String uri) throws IOException {
		URI u = URI.createURI(uri);
		if (u != null)
			return rset.getURIConverter().createInputStream(u);
		return null;
	}

	@Override
	public Object createComponent(Object callingContext, Object model,
			Object creationHint) {
		if (model instanceof String) {
			Matcher m = PATTERN.matcher((String) model);
			if (m.matches())
				return new ResourceCodeDescriptor(m.group(PATTERN_BUNDLE),
						m.group(PATTERN_PATH));
		}
		return null;
	}

	@Override
	public String getFactoryID() {
		return FACTORY_ID;
	}

	@Override
	public boolean isFactoryFor(Object callingContext, Object model, Object creationHint) {
		if (!(model instanceof String))
			return false;
		Matcher m = PATTERN.matcher((String) model);
		if (m.matches()) {
			String language = m.group(PATTERN_LANGUAGE);
			return language == null || LANGUAGE.equals(language);
		}
		return false;
	}
}