| /******************************************************************************* |
| * Copyright (c) 2005, 2008 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.ltk.core.refactoring; |
| |
| import org.eclipse.core.runtime.IProgressMonitor; |
| import org.eclipse.core.runtime.PlatformObject; |
| |
| import org.eclipse.ltk.core.refactoring.history.IRefactoringHistoryService; |
| import org.eclipse.ltk.core.refactoring.history.RefactoringHistory; |
| import org.eclipse.ltk.internal.core.refactoring.history.RefactoringHistoryService; |
| |
| /** |
| * Proxy of a refactoring descriptor. |
| * <p> |
| * Refactoring descriptors are exposed by the refactoring history service as |
| * lightweight proxy objects. Refactoring descriptor proxies have an efficient |
| * memory representation and are therefore suited to model huge refactoring |
| * histories which may be displayed in the user interface. The refactoring |
| * history service may hand out any number of proxies for a given descriptor. |
| * Proxies only offer direct access to the time stamp {@link #getTimeStamp()}, |
| * the related project {@link #getProject()} and description |
| * {@link #getDescription()}. In order to access other information such as |
| * arguments and comments, clients have to call |
| * {@link #requestDescriptor(IProgressMonitor)} in order to obtain the actual |
| * refactoring descriptor. |
| * </p> |
| * <p> |
| * Refactoring descriptors are potentially heavy weight objects which should not |
| * be held on to. Proxies which are retrieved from external sources (e.g. not |
| * from the local refactoring history service) may encapsulate refactoring |
| * descriptors and should not be held in memory as well. |
| * </p> |
| * <p> |
| * All time stamps are measured as the milliseconds since January 1, 1970, |
| * 00:00:00 GMT. |
| * </p> |
| * <p> |
| * Note: this class is not intended to be subclassed by clients. |
| * </p> |
| * |
| * @see IRefactoringHistoryService |
| * @see RefactoringHistory |
| * |
| * @since 3.2 |
| * |
| * @noextend This class is not intended to be subclassed by clients. |
| */ |
| public abstract class RefactoringDescriptorProxy extends PlatformObject implements Comparable { |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public int compareTo(final Object object) { |
| if (object instanceof RefactoringDescriptorProxy) { |
| final RefactoringDescriptorProxy proxy= (RefactoringDescriptorProxy) object; |
| final long delta= getTimeStamp() - proxy.getTimeStamp(); |
| if (delta > 0) |
| return 1; |
| else if (delta < 0) |
| return -1; |
| return 0; |
| } |
| return 0; |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public final boolean equals(final Object object) { |
| if (object instanceof RefactoringDescriptorProxy) { |
| final RefactoringDescriptorProxy proxy= (RefactoringDescriptorProxy) object; |
| return getTimeStamp() == proxy.getTimeStamp() && getDescription().equals(proxy.getDescription()); |
| } |
| return false; |
| } |
| |
| /** |
| * Returns a human-readable description of refactoring. |
| * |
| * @return a description of the refactoring |
| */ |
| public abstract String getDescription(); |
| |
| /** |
| * Returns the name of the associated project. |
| * |
| * @return the non-empty name of the project, or <code>null</code> |
| */ |
| public abstract String getProject(); |
| |
| /** |
| * Returns the time stamp of this refactoring. |
| * |
| * @return the time stamp, or <code>-1</code> if no time information is |
| * available |
| */ |
| public abstract long getTimeStamp(); |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public final int hashCode() { |
| int code= getDescription().hashCode(); |
| final long stamp= getTimeStamp(); |
| if (stamp >= 0) |
| code+= (17 * stamp); |
| return code; |
| } |
| |
| /** |
| * Resolves this proxy and returns the associated refactoring descriptor. |
| * <p> |
| * Clients must connect to the refactoring history service first before |
| * calling this method. |
| * </p> |
| * |
| * @param monitor |
| * the progress monitor to use, or <code>null</code> |
| * |
| * @return the refactoring descriptor, or <code>null</code> |
| */ |
| public RefactoringDescriptor requestDescriptor(final IProgressMonitor monitor) { |
| return RefactoringHistoryService.getInstance().requestDescriptor(this, monitor); |
| } |
| } |