| /******************************************************************************* |
| * Copyright (c) 2000, 2011 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.compare.structuremergeviewer; |
| |
| import org.eclipse.compare.ITypedElement; |
| import org.eclipse.swt.graphics.Image; |
| |
| /** |
| * Interface for objects used as input to a two-way or three-way compare viewer. |
| * It defines API for accessing the three sides for the compare, |
| * and a name and image which is used when displaying the three way input |
| * in the UI, for example, in a title bar. |
| * <p> |
| * Note: at most two sides of an {@code ICompareInput} can be {@code null}, |
| * (as it is normal for additions or deletions) but not all three. |
| * <p> |
| * {@code ICompareInput} provides methods for registering |
| * {@link ICompareInputChangeListener}s |
| * that get informed if one (or more) |
| * of the three sides of an {@code ICompareInput} object changes its value. |
| * <p> |
| * For example when accepting an incoming addition |
| * the (non-{@code null}) left side of an {@code ICompareInput} |
| * is copied to the right side by means of method {@code copy}. |
| * This should trigger a call to {@link ICompareInputChangeListener#compareInputChanged} of registered |
| * {@link ICompareInputChangeListener}s. |
| * <p> |
| * Clients can implement this interface, or use the convenience implementation |
| * {@link DiffNode}. |
| * |
| * @see StructureDiffViewer |
| * @see org.eclipse.compare.contentmergeviewer.ContentMergeViewer |
| * @see DiffNode |
| */ |
| public interface ICompareInput { |
| /** |
| * Returns name of input. |
| * This name is displayed when this input is shown in a viewer. |
| * In many cases this name is the name of one of the non-{@code null} sides or a combination |
| * thereof. |
| * |
| * @return name of input |
| */ |
| String getName(); |
| |
| /** |
| * Returns an image representing this input. |
| * This image is typically displayed when this input is shown in a viewer. |
| * In many cases this image is the image of one of the non-{@code null} sides. |
| * |
| * @return image representing this input, or {@code null} if no icon should be shown |
| */ |
| Image getImage(); |
| |
| /** |
| * Returns the kind of difference between the three sides ancestor, left and right. |
| * This field is only meaningful if the {@code ICompareInput} is the result of another |
| * compare. In this case it is used together with {@link #getImage()} to compose an icon |
| * which reflects the kind of difference between the two or three elements. |
| * |
| * @return kind of difference (see {@link Differencer}) |
| */ |
| int getKind(); |
| |
| /** |
| * Returns the ancestor side of this input. |
| * Returns {@code null} if this input has no ancestor |
| * or in the two-way compare case. |
| * |
| * @return the ancestor of this input, or {@code null} |
| */ |
| ITypedElement getAncestor(); |
| |
| /** |
| * Returns the left side of this input. |
| * Returns {@code null} if there is no left side (deletion or addition). |
| * |
| * @return the left side of this input, or {@code null} |
| */ |
| ITypedElement getLeft(); |
| |
| /** |
| * Returns the right side of this input. |
| * Returns {@code null} if there is no right side (deletion or addition). |
| * |
| * @return the right side of this input, or {@code null} |
| */ |
| ITypedElement getRight(); |
| |
| /** |
| * Registers the given listener for notification. |
| * If the identical listener is already registered the method has no effect. |
| * |
| * @param listener the listener to register for changes of this input |
| */ |
| void addCompareInputChangeListener(ICompareInputChangeListener listener); |
| |
| /** |
| * Unregisters the given listener. |
| * If the identical listener is not registered the method has no effect. |
| * |
| * @param listener the listener to unregister |
| */ |
| void removeCompareInputChangeListener(ICompareInputChangeListener listener); |
| |
| /** |
| * Copy one side (source) to the other side (destination) depending on the |
| * value of {@code leftToRight}. This method is called from |
| * a merge viewer if a corresponding action ("take left" or "take right") |
| * has been pressed. |
| * <p> |
| * The implementation should handle the following cases: |
| * <ul> |
| * <li> |
| * if the source side is {@code null} the destination must be deleted, |
| * <li> |
| * if the destination is {@code null} the destination must be created |
| * and filled with the contents from the source, |
| * <li> |
| * if both sides are non-{@code null} the contents of source must be copied to destination. |
| * </ul> |
| * In addition the implementation should send out notification to the registered |
| * {@link ICompareInputChangeListener}. |
| * |
| * @param leftToRight if {@code true} the left side is copied to the right side. |
| * If {@code false} the right side is copied to the left side |
| */ |
| void copy(boolean leftToRight); |
| } |
| |