Copyright (c) 2000, 2010 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) 2000, 2010 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.jdt.internal.core;

import java.io.File;

import org.eclipse.core.resources.IResource;
import org.eclipse.core.runtime.IPath;
import org.eclipse.jdt.core.IJavaElement;
import org.eclipse.jdt.core.IPackageFragmentRoot;
import org.eclipse.jdt.core.JavaModelException;

A package fragment root that corresponds to an external class folder.
NOTE: An external package fragment root never has an associated resource.
See Also:
IPackageFragmentRoot
PackageFragmentRootInfo/**
 * A package fragment root that corresponds to an external class folder.
 *
 * <p>NOTE: An external package fragment root never has an associated resource.
 *
 * @see org.eclipse.jdt.core.IPackageFragmentRoot
 * @see org.eclipse.jdt.internal.core.PackageFragmentRootInfo
 */
public class ExternalPackageFragmentRoot extends PackageFragmentRoot {

	
The path to the external folder
(an OS path)
/**
	 * The path to the external folder
	 * (an OS path)
	 */
	protected final IPath externalPath;

	
Constructs a package fragment root which is the root of the Java package directory hierarchy
based on an external folder that is not contained in a IJavaProject and
does not have an associated IResource.
/**
	 * Constructs a package fragment root which is the root of the Java package directory hierarchy
	 * based on an external folder that is not contained in a <code>IJavaProject</code> and
	 * does not have an associated <code>IResource</code>.
	 */
	protected ExternalPackageFragmentRoot(IPath externalPath, JavaProject project) {
		super(null, project);
		this.externalPath = externalPath;
	}

	protected ExternalPackageFragmentRoot(IResource linkedFolder, IPath externalPath, JavaProject project) {
		super(linkedFolder, project);
		this.externalPath = externalPath == null ? linkedFolder.getLocation() : externalPath;
	}

	
An external class folder is always K_BINARY.
/**
	 * An external class folder is always K_BINARY.
	 */
	@Override
	protected int determineKind(IResource underlyingResource) {
		return IPackageFragmentRoot.K_BINARY;
	}
	
Returns true if this handle represents the same external folder
as the given handle.
See Also:
equals.equals/**
	 * Returns true if this handle represents the same external folder
	 * as the given handle.
	 *
	 * @see Object#equals
	 */
	@Override
	public boolean equals(Object o) {
		if (this == o)
			return true;
		if (o instanceof ExternalPackageFragmentRoot) {
			ExternalPackageFragmentRoot other= (ExternalPackageFragmentRoot) o;
			return this.externalPath.equals(other.externalPath);
		}
		return false;
	}
	@Override
	public String getElementName() {
		return this.externalPath.lastSegment();
	}
	
See Also:
IPackageFragmentRoot/**
	 * @see IPackageFragmentRoot
	 */
	@Override
	public int getKind() {
		return IPackageFragmentRoot.K_BINARY;
	}
	@Override
	int internalKind() throws JavaModelException {
		return IPackageFragmentRoot.K_BINARY;
	}
	
See Also:
IPackageFragmentRoot/**
	 * @see IPackageFragmentRoot
	 */
	@Override
	public IPath getPath() {
		return this.externalPath;
	}

	
See Also:
IJavaElement/**
	 * @see IJavaElement
	 */
	@Override
	public IResource getUnderlyingResource() throws JavaModelException {
		return null;
	}
	@Override
	public int hashCode() {
		return this.externalPath.hashCode();
	}
	
See Also:
IPackageFragmentRoot/**
	 * @see IPackageFragmentRoot
	 */
	@Override
	public boolean isExternal() {
		return true;
	}

	@Override
	public IResource resource(PackageFragmentRoot root) {
		if (this.resource == null)
			return this.resource = JavaModelManager.getExternalManager().getFolder(this.externalPath);
		return super.resource(root);
	}

	@Override
	protected boolean resourceExists(IResource underlyingResource) {
		if (underlyingResource == null)
			return false;
		IPath location = underlyingResource.getLocation();
		if (location == null)
			return false;
		File file = location.toFile();
		if (file == null)
			return false;
		return file.exists();
	}

	@Override
	protected void toStringAncestors(StringBuffer buffer) {
		// don't show project as it is irrelevant for external folders.
	}
}