org.eclipse.osgi.internal.loader.buddy.DependentPolicy Maven / Gradle / Ivy

Show more of this group Show more artifacts with this name
Show all versions of aspectjtools Show documentation

AspectJ tools most notably contains the AspectJ compiler (AJC). AJC applies aspects to Java classes during compilation, fully replacing Javac for plain Java classes and also compiling native AspectJ or annotation-based @AspectJ syntax. Furthermore, AJC can weave aspects into existing class files in a post-compile binary weaving step. This library is a superset of AspectJ weaver and hence also of AspectJ runtime.

There is a newer version: 1.9.22.1

Show newest version

/*******************************************************************************
 * Copyright (c) 2005, 2016 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
 *******************************************************************************/

package org.eclipse.osgi.internal.loader.buddy;

import java.io.IOException;
import java.net.URL;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.List;
import java.util.Set;
import org.eclipse.osgi.container.ModuleWire;
import org.eclipse.osgi.container.ModuleWiring;
import org.eclipse.osgi.internal.loader.BundleLoader;
import org.osgi.framework.namespace.BundleNamespace;
import org.osgi.framework.namespace.PackageNamespace;

/**
 * DependentPolicy is an implementation of a buddy policy.
 * It is responsible for looking up a class in the dependents of the bundle
 * to which this policy is attached to.
 */
public class DependentPolicy implements IBuddyPolicy {
	BundleLoader buddyRequester;
	int lastDependentOfAdded = -1; //remember the index of the bundle for which we last added the dependent
	List allDependents = null; //the list of all dependents known so far

	public DependentPolicy(BundleLoader requester) {
		buddyRequester = requester;

		//Initialize with the first level of dependent the list
		allDependents = new ArrayList<>();
		basicAddImmediateDependents(requester.getWiring());
		//If there is no dependent, reset to null
		if (allDependents.size() == 0)
			allDependents = null;
	}

	@Override
	public Class loadClass(String name) {
		if (allDependents == null) {
			return null;
		}
		//size may change, so we must check it every time
		for (int i = 0; i < allDependents.size(); i++) {
			ModuleWiring searchWiring = allDependents.get(i);
			BundleLoader searchLoader = (BundleLoader) searchWiring.getModuleLoader();
			if (searchLoader != null) {
				Class result = searchLoader.findClassNoParentNoException(name);
				if (result != null) {
					return result;
				}
				addDependent(i, searchWiring);
			}
		}
		return null;
	}

	private synchronized void addDependent(int i, ModuleWiring searchedWiring) {
		if (i > lastDependentOfAdded) {
			lastDependentOfAdded = i;
			basicAddImmediateDependents(searchedWiring);
		}
	}

	@Override
	public URL loadResource(String name) {
		if (allDependents == null)
			return null;

		URL result = null;
		//size may change, so we must check it every time
		for (int i = 0; i < allDependents.size() && result == null; i++) {
			ModuleWiring searchWiring = allDependents.get(i);
			BundleLoader searchLoader = (BundleLoader) searchWiring.getModuleLoader();
			if (searchLoader != null) {
				result = searchLoader.findResource(name);
				if (result == null) {
					addDependent(i, searchWiring);
				}
			}
		}
		return result;
	}

	@Override
	public Enumeration loadResources(String name) {
		if (allDependents == null)
			return null;

		Enumeration results = null;
		//size may change, so we must check it every time
		for (int i = 0; i < allDependents.size(); i++) {
			ModuleWiring searchWiring = allDependents.get(i);
			BundleLoader searchLoader = (BundleLoader) searchWiring.getModuleLoader();
			if (searchLoader != null) {
				try {
					results = BundleLoader.compoundEnumerations(results, searchLoader.findResources(name));
					addDependent(i, searchWiring);
				} catch (IOException e) {
					//Ignore and keep looking
				}
			}
		}
		return results;
	}

	@Override
	public void addListResources(Set results, String path, String filePattern, int options) {
		if (allDependents == null) {
			return;
		}
		// size may change, so we must check it every time
		for (int i = 0; i < allDependents.size(); i++) {
			ModuleWiring searchWiring = allDependents.get(i);
			results.addAll(searchWiring.listResources(path, filePattern, options));
			addDependent(i, searchWiring);
		}
	}

	private void basicAddImmediateDependents(ModuleWiring wiring) {
		List providedWires = wiring.getProvidedModuleWires(null);
		if (providedWires != null) {
			for (ModuleWire wire : providedWires) {
				String namespace = wire.getRequirement().getNamespace();
				if (PackageNamespace.PACKAGE_NAMESPACE.equals(namespace) || BundleNamespace.BUNDLE_NAMESPACE.equals(namespace)) {
					ModuleWiring dependent = wire.getRequirerWiring();
					if (!allDependents.contains(dependent)) {
						allDependents.add(dependent);
					}
				}
			}
		}
	}
}