Copyright (c) 2012 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
/*******************************************************************************
 * Copyright (c) 2012 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.container;

import org.osgi.framework.wiring.BundleWire;

An implementation of BundleWire. 
Since:
3.10/**
 * An implementation of {@link BundleWire}.
 * @since 3.10
 */
public final class ModuleWire implements BundleWire {
	private final ModuleCapability capability;
	private final ModuleRevision hostingProvider;
	private final ModuleRequirement requirement;
	private final ModuleRevision hostingRequirer;
	// indicates that the wire points to valid wirings
	// technically this should be a separate flag for requirer vs provider but that seems like overkill
	private volatile boolean isValid = true;

	ModuleWire(ModuleCapability capability, ModuleRevision hostingProvider, ModuleRequirement requirement, ModuleRevision hostingRequirer) {
		super();
		this.capability = capability;
		this.hostingProvider = hostingProvider;
		this.requirement = requirement;
		this.hostingRequirer = hostingRequirer;
	}

	@Override
	public ModuleCapability getCapability() {
		return capability;
	}

	@Override
	public ModuleRequirement getRequirement() {
		return requirement;
	}

	@Override
	public ModuleWiring getProviderWiring() {
		if (!isValid) {
			return null;
		}
		return hostingProvider.getWiring();
	}

	@Override
	public ModuleWiring getRequirerWiring() {
		if (!isValid) {
			return null;
		}
		return hostingRequirer.getWiring();
	}

	@Override
	public ModuleRevision getProvider() {
		return hostingProvider;
	}

	@Override
	public ModuleRevision getRequirer() {
		return hostingRequirer;
	}

	@Override
	public String toString() {
		return getRequirement() + " -> " + getCapability(); //$NON-NLS-1$
	}

	void invalidate() {
		this.isValid = false;
	}

}