Copyright (c) 2005, 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
/*******************************************************************************
 * Copyright (c) 2005, 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
 *******************************************************************************/
package org.eclipse.core.commands.operations;

import org.eclipse.core.runtime.IAdaptable;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.Status;


An operation approver that enforces a strict linear undo. It does not allow
the undo or redo of any operation that is not the latest available operation
in all of its undo contexts.  This class may be instantiated by clients.

Since:
3.1/**
 * <p>
 * An operation approver that enforces a strict linear undo. It does not allow
 * the undo or redo of any operation that is not the latest available operation
 * in all of its undo contexts.  This class may be instantiated by clients.
 * </p>
 *
 * @since 3.1
 */
public final class LinearUndoEnforcer extends LinearUndoViolationDetector {
	
Create an instance of LinearUndoEnforcer.
/**
	 * Create an instance of LinearUndoEnforcer.
	 */
	public LinearUndoEnforcer() {
		super();
	}

	/*
	 * Return whether a linear redo violation is allowable.  A linear redo violation
	 * is defined as a request to redo a particular operation even if it is not the most
	 * recently added operation to the redo history.
	 */
	@Override
	protected IStatus allowLinearRedoViolation(IUndoableOperation operation,
			IUndoContext context, IOperationHistory history, IAdaptable uiInfo) {
		return Status.CANCEL_STATUS;
	}

	/*
	 * Return whether a linear undo violation is allowable.  A linear undo violation
	 * is defined as a request to undo a particular operation even if it is not the most
	 * recently added operation to the undo history.
	 */
	@Override
	protected IStatus allowLinearUndoViolation(IUndoableOperation operation,
			IUndoContext context, IOperationHistory history, IAdaptable uiInfo) {
		return Status.CANCEL_STATUS;
	}

}