Copyright (c) 2000, 2015 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
    Stephan Herrmann - Contribution for
							Bug 458577 - IClassFile.getWorkingCopy() may lead to NPE in BecomeWorkingCopyOperation
/*******************************************************************************
 * Copyright (c) 2000, 2015 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
 *     Stephan Herrmann - Contribution for
 *								Bug 458577 - IClassFile.getWorkingCopy() may lead to NPE in BecomeWorkingCopyOperation
 *******************************************************************************/
package org.eclipse.jdt.internal.core;

import org.eclipse.core.resources.IResource;
import org.eclipse.jdt.core.*;

Switch and ICompilationUnit to working copy mode
and signal the working copy addition through a delta.
/**
 * Switch and ICompilationUnit to working copy mode
 * and signal the working copy addition through a delta.
 */
public class BecomeWorkingCopyOperation extends JavaModelOperation {

	IProblemRequestor problemRequestor;

	/*
	 * Creates a BecomeWorkingCopyOperation for the given working copy.
	 * perOwnerWorkingCopies map is not null if the working copy is a shared working copy.
	 */
	public BecomeWorkingCopyOperation(CompilationUnit workingCopy, IProblemRequestor problemRequestor) {
		super(new IJavaElement[] {workingCopy});
		this.problemRequestor = problemRequestor;
	}
	@Override
	protected void executeOperation() throws JavaModelException {

		// open the working copy now to ensure contents are that of the current state of this element
		CompilationUnit workingCopy = getWorkingCopy();
		JavaModelManager.getJavaModelManager().getPerWorkingCopyInfo(workingCopy, true/*create if needed*/, true/*record usage*/, this.problemRequestor);
		workingCopy.openWhenClosed(workingCopy.createElementInfo(), true, this.progressMonitor);

		if (!workingCopy.isPrimary()) {
			// report added java delta for a non-primary working copy
			JavaElementDelta delta = new JavaElementDelta(getJavaModel());
			delta.added(workingCopy);
			addDelta(delta);
		} else {
			IResource resource = workingCopy.getResource();
			if (resource != null) {
				if (resource.isAccessible()) {
					// report a F_PRIMARY_WORKING_COPY change delta for a primary working copy
					JavaElementDelta delta = new JavaElementDelta(getJavaModel());
					delta.changed(workingCopy, IJavaElementDelta.F_PRIMARY_WORKING_COPY);
					addDelta(delta);
				} else {
					// report an ADDED delta
					JavaElementDelta delta = new JavaElementDelta(getJavaModel());
					delta.added(workingCopy, IJavaElementDelta.F_PRIMARY_WORKING_COPY);
					addDelta(delta);
				}
			}
		}

		this.resultElements = new IJavaElement[] {workingCopy};
	}
	/*
	 * Returns the working copy this operation is working on.
	 */
	protected CompilationUnit getWorkingCopy() {
		return (CompilationUnit)getElementToProcess();
	}
	/*
	 * @see JavaModelOperation#isReadOnly
	 */
	@Override
	public boolean isReadOnly() {
		return true;
	}

}