/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.apache.uima.caseditor.editor;
import java.util.HashMap;
import java.util.Map;
import org.apache.uima.cas.CAS;
import org.apache.uima.caseditor.CasEditorPlugin;
import org.eclipse.ui.IEditorInput;
import org.eclipse.ui.IPartListener;
import org.eclipse.ui.IWorkbenchPart;
import org.eclipse.ui.PartInitException;
import org.eclipse.ui.part.IPage;
import org.eclipse.ui.part.IPageBookViewPage;
import org.eclipse.ui.part.MessagePage;
import org.eclipse.ui.part.PageBook;
import org.eclipse.ui.part.PageBookView;
/**
* Base class for views which show information about the {@link CAS} opened
* in the editor.
* <p>
* The view page created with {@link #doCreatePage(ICasEditor)} will be disposed
* and re-created on every Cas Editor input change or CAS view change.
* <p>
* In the case the view should no be re-created on a CAS view change
* {@link #isRecreatePageOnCASViewSwitch()} must be overridden and return false.
*
*/
public abstract class CasEditorView extends PageBookView {
private final String editorNotAvailableMessage;
private Map<ICasEditor, ICasEditorInputListener> editorListenerMap =
new HashMap<ICasEditor, ICasEditorInputListener>();
private Map<ICasEditor, ICasDocumentListener> documentListenerMap =
new HashMap<ICasEditor, ICasDocumentListener>();
public CasEditorView(String editorNotAvailableMessage) {
this.editorNotAvailableMessage = editorNotAvailableMessage;
}
/**
* Implementors should overwrite if they want that. Default is false.
* <p>
* Note:<br>
* The implementation uses the ICasDocumentListener.viewChanged event
* to recognize view changes. If the view implementation also listens for
* this event the view might already be disposed when the listener is called.
* It is therefore strongly recommended either to listen for the event and
* update the view or don't list for the event and rely on a page re-creation.
*
* @return true if page should be disposed/re-created on CAS view change,
* or false if not.
*/
protected boolean isRecreatePageOnCASViewSwitch() {
return false;
}
@Override
protected IPage createDefaultPage(PageBook book) {
MessagePage page = new MessagePage();
initPage(page);
page.createControl(book);
page.setMessage(editorNotAvailableMessage);
return page;
}
// Creates a new page if document is available and CAS view is compatible
// Will be recreated on view switch (need a flag to disable that) and input cas switch
protected abstract IPageBookViewPage doCreatePage(ICasEditor editor);
private void createViewPage( CasEditorViewPage casViewPageBookedPage, ICasEditor editor) {
IPageBookViewPage page = doCreatePage(editor);
if (page != null) {
try {
page.init(new SubPageSite(casViewPageBookedPage.getSite()));
} catch (PartInitException e) {
CasEditorPlugin.log(e);
}
casViewPageBookedPage.setCASViewPage(page);
}
else {
casViewPageBookedPage.setCASViewPage(null);
}
}
@Override
protected final PageRec doCreatePage(final IWorkbenchPart part) {
PageRec result = null;
if (part instanceof ICasEditor) {
final ICasEditor editor = (ICasEditor) part;
final CasEditorViewPage casViewPageBookedPage = new CasEditorViewPage(editorNotAvailableMessage);
if (editor.getDocument() != null) {
ICasDocumentListener documentListener = new AbstractDocumentListener() {
@Override
public void viewChanged(String oldViewName, String newViewName) {
if (isRecreatePageOnCASViewSwitch()) {
createViewPage(casViewPageBookedPage, editor);
}
}
};
editor.getDocument().addChangeListener(documentListener);
// remember on map
documentListenerMap.put(editor, documentListener);
}
ICasEditorInputListener inputListener = new ICasEditorInputListener() {
public void casDocumentChanged(IEditorInput oldInput, ICasDocument oldDocument,
IEditorInput newInput, ICasDocument newDocument) {
createViewPage(casViewPageBookedPage, editor);
ICasDocumentListener changeListener = documentListenerMap.get(editor);
if (changeListener != null) {
if (oldDocument != null)
oldDocument.removeChangeListener(changeListener);
if (newDocument != null)
newDocument.addChangeListener(changeListener);
}
}
};
editorListenerMap.put(editor, inputListener);
editor.addCasEditorInputListener(inputListener);
// BUG: This does not work!
initPage(casViewPageBookedPage);
casViewPageBookedPage.createControl(getPageBook());
createViewPage(casViewPageBookedPage, editor);
result = new PageRec(editor, casViewPageBookedPage);
}
return result;
}
@Override
protected IWorkbenchPart getBootstrapPart() {
return getSite().getPage().getActiveEditor();
}
@Override
protected void doDestroyPage(IWorkbenchPart part, PageRec pageRecord) {
if (part instanceof ICasEditor) {
ICasEditor editor = (ICasEditor) part;
ICasEditorInputListener editorListener = editorListenerMap.remove(part);
if (editorListener != null) {
editor.removeCasEditorInputListener(editorListener);
}
ICasDocumentListener documentListener = documentListenerMap.remove(part);
ICasDocument document = editor.getDocument();
if (documentListener != null && document != null) {
document.removeChangeListener(documentListener);
}
}
pageRecord.page.dispose();
pageRecord.dispose();
}
@Override
protected boolean isImportant(IWorkbenchPart part) {
// only interested in annotation editors
return part instanceof AnnotationEditor;
}
/**
* Look at {@link IPartListener#partBroughtToTop(IWorkbenchPart)}.
*
* @param part
*/
@Override
public void partBroughtToTop(IWorkbenchPart part) {
partActivated(part);
}
@Override
public void dispose() {
for (Map.Entry<ICasEditor, ICasEditorInputListener> entry :
editorListenerMap.entrySet()) {
entry.getKey().removeCasEditorInputListener(entry.getValue());
}
editorListenerMap.clear();
for (Map.Entry<ICasEditor, ICasDocumentListener> entry :
documentListenerMap.entrySet()) {
ICasDocument document = entry.getKey().getDocument();
if (document != null)
document.removeChangeListener(entry.getValue());
}
documentListenerMap.clear();
super.dispose();
}
}