| /******************************************************************************* |
| * Copyright (c) 2006 IBM Corporation and others. |
| * All rights reserved. This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License v1.0 |
| * which accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/epl-v10.html |
| * |
| * 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; |
| |
| /** |
| * Extends {@link IOperationApprover} to approve the execution of a particular |
| * operation within an operation history. Operations that are candidates for |
| * execution have already been validated against their current state and |
| * according to the rules of the history. Prior to 3.2, an operation approver |
| * was only consulted for undo and redo of an operation, not its initial |
| * execution. |
| * <p> |
| * By the time an IOperationApprover2 is consulted, the execution has already |
| * been requested and it has been determined that the operation is valid. |
| * Approvers should return an <code>IStatus</code> object with severity |
| * <code>OK</code> if the operation should proceed, and any other severity if |
| * it should not. When an operation is not approved, it is expected that the |
| * object not allowing the operation has already consulted the user if necessary |
| * or otherwise provided any necessary information to the user about the fact |
| * that the operation is not approved. |
| * </p> |
| * <p> |
| * Like {@link IOperationApprover}, implementers of this extension must be |
| * prepared to receive the approval messages from a background thread. Any UI |
| * access occurring inside the implementation must be properly synchronized |
| * using the techniques specified by the client's widget library. |
| * </p> |
| * |
| * @since 3.2 |
| */ |
| public interface IOperationApprover2 extends IOperationApprover { |
| /** |
| * Return a status indicating whether the specified operation should be |
| * executed. Any status that does not have severity <code>IStatus.OK</code> |
| * will not be approved. Implementers should not assume that the execution |
| * will be performed when the status is <code>OK</code>, since other |
| * operation approvers may veto the execution. |
| * |
| * @param operation |
| * the operation to be executed |
| * @param history |
| * the history performing the execution of the operation |
| * @param info |
| * the IAdaptable (or <code>null</code>) provided by the |
| * caller in order to supply UI information for prompting the |
| * user if necessary. When this parameter is not |
| * <code>null</code>, it should minimally contain an adapter |
| * for the org.eclipse.swt.widgets.Shell.class. Even if UI |
| * information is provided, the implementation of this method |
| * must be prepared for being called from a background thread. |
| * Any UI access must be properly synchronized using the |
| * techniques specified by the client's widget library. |
| * @return the IStatus describing whether the operation is approved. The |
| * execution will not proceed if the status severity is not |
| * <code>OK</code>, and the caller requesting the execution will |
| * be returned the status that caused the rejection. Any other |
| * status severities will not be interpreted by the history. |
| */ |
| IStatus proceedExecuting(IUndoableOperation operation, |
| IOperationHistory history, IAdaptable info); |
| } |
