| package test.wksp.eclipse; |
| |
| /** |
| * A compare operation which can present its results in a special editor. |
| * Running the compare operation and presentating the results in a compare |
| * editor are combined in one class because it allows a client to keep the |
| * implementation all in one place while separating it from the innards of a |
| * specific UI implementation of compare/merge. |
| * <p> |
| * A <code>CompareEditorInput</code> defines methods for the following sequence |
| * steps: |
| * <UL> |
| * <LI>running a lengthy compare operation under progress monitor control, |
| * <LI>creating a UI for displaying the model and initializing the some widgets |
| * with the compare result, |
| * <LI>tracking the dirty state of the model in case of merge, |
| * <LI>saving the model. |
| * </UL> |
| * The Compare plug-in's <code>openCompareEditor</code> method takes an |
| * <code>ICompareEditorInput</code> and starts sequencing through the above |
| * steps. If the compare result is not empty a new compare editor is opened and |
| * takes over the sequence until eventually closed. |
| * <p> |
| * The <code>prepareInput</code> method should contain the code of the compare |
| * operation. It is executed under control of a progress monitor and can be |
| * canceled. If the result of the compare is not empty, that is if there are |
| * differences that needs to be presented, the <code>ICompareEditorInput</code> |
| * should hold onto them and return them with the <code>getCompareResult</code> |
| * method. If the value returned from <code>getCompareResult</code> is not |
| * <code>null</code> a compare editor is opened on the |
| * <code>ICompareEditorInput</code> with title and title image initialized by |
| * the corresponding methods of the <code>ICompareEditorInput</code>. |
| * <p> |
| * Creation of the editor's SWT controls is delegated to the |
| * <code>createContents</code> method. Here the SWT controls must be created and |
| * initialized with the result of the compare operation. |
| * <p> |
| * If merging is allowed, the modification state of the compared constituents |
| * must be tracked and the dirty state returned from method |
| * <code>isSaveNeeded</code>. The value <code>true</code> triggers a subsequent |
| * call to <code>save</code> where the modified resources can be saved. |
| * <p> |
| * The most important part of this implementation is the setup of the |
| * compare/merge UI. The UI uses a simple browser metaphor to present compare |
| * results. The top half of the layout shows the structural compare results |
| * (e.g. added, deleted, and changed files), the bottom half the content compare |
| * results (e.g. textual differences between two files). A selection in the top |
| * pane is fed to the bottom pane. If a content viewer is registered for the |
| * type of the selected object, this viewer is installed in the pane. In |
| * addition if a structure viewer is registered for the selection type the top |
| * pane is split horizontally to make room for another pane and the structure |
| * viewer is installed in it. When comparing Java files this second structure |
| * viewer would show the structural differences within a Java file, e.g. added, |
| * deleted or changed methods and fields. |
| * <p> |
| * Subclasses provide custom setups, e.g. for a Catchup/Release operation by |
| * passing a subclass of <code>CompareConfiguration</code> and by implementing |
| * the <code>prepareInput</code> method. If a subclass cannot use the |
| * <code>DiffTreeViewer</code> which is installed by default in the top left |
| * pane, method <code>createDiffViewer</code> can be overridden. |
| * |
| * @see CompareUI |
| * @see CompareEditorInput |
| */ |
| public class X08 { |
| |
| } |
