Java tutorial
/******************************************************************************* * Copyright (c) 2000, 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 eu.udig.jconsole; import java.text.MessageFormat; import java.util.ArrayList; import java.util.List; import org.eclipse.swt.widgets.Composite; import org.eclipse.swt.widgets.Control; import org.eclipse.jface.viewers.ISelection; import org.eclipse.jface.viewers.IStructuredSelection; import org.eclipse.jface.viewers.ITreeContentProvider; import org.eclipse.jface.viewers.LabelProvider; import org.eclipse.jface.viewers.SelectionChangedEvent; import org.eclipse.jface.viewers.TreeViewer; import org.eclipse.jface.viewers.Viewer; import org.eclipse.jface.text.BadLocationException; import org.eclipse.jface.text.BadPositionCategoryException; import org.eclipse.jface.text.DefaultPositionUpdater; import org.eclipse.jface.text.IDocument; import org.eclipse.jface.text.IPositionUpdater; import org.eclipse.jface.text.Position; import org.eclipse.ui.views.contentoutline.ContentOutlinePage; import org.eclipse.ui.texteditor.IDocumentProvider; import org.eclipse.ui.texteditor.ITextEditor; /** * A content outline page which always represents the content of the * connected editor in 10 segments. */ public class JavaContentOutlinePage extends ContentOutlinePage { /** * A segment element. */ protected static class Segment { public String name; public Position position; public Segment(String name, Position position) { this.name = name; this.position = position; } public String toString() { return name; } } /** * Divides the editor's document into ten segments and provides elements for them. */ protected class ContentProvider implements ITreeContentProvider { protected final static String SEGMENTS = "__java_segments"; //$NON-NLS-1$ protected IPositionUpdater fPositionUpdater = new DefaultPositionUpdater(SEGMENTS); protected List fContent = new ArrayList(10); protected void parse(IDocument document) { int lines = document.getNumberOfLines(); int increment = Math.max(Math.round(lines / 10f), 10); for (int line = 0; line < lines; line += increment) { int length = increment; if (line + increment > lines) length = lines - line; try { int offset = document.getLineOffset(line); int end = document.getLineOffset(line + length); length = end - offset; Position p = new Position(offset, length); document.addPosition(SEGMENTS, p); fContent.add(new Segment( MessageFormat.format(JavaEditorMessages.getString("OutlinePage.segment.title_pattern"), //$NON-NLS-1$ new Object[] { new Integer(offset) }), p)); } catch (BadPositionCategoryException x) { } catch (BadLocationException x) { } } } /* * @see IContentProvider#inputChanged(Viewer, Object, Object) */ public void inputChanged(Viewer viewer, Object oldInput, Object newInput) { if (oldInput != null) { IDocument document = fDocumentProvider.getDocument(oldInput); if (document != null) { try { document.removePositionCategory(SEGMENTS); } catch (BadPositionCategoryException x) { } document.removePositionUpdater(fPositionUpdater); } } fContent.clear(); if (newInput != null) { IDocument document = fDocumentProvider.getDocument(newInput); if (document != null) { document.addPositionCategory(SEGMENTS); document.addPositionUpdater(fPositionUpdater); parse(document); } } } /* * @see IContentProvider#dispose */ public void dispose() { if (fContent != null) { fContent.clear(); fContent = null; } } /* * @see IStructuredContentProvider#getElements(Object) */ public Object[] getElements(Object element) { return fContent.toArray(); } /* * @see ITreeContentProvider#hasChildren(Object) */ public boolean hasChildren(Object element) { return element == fInput; } /* * @see ITreeContentProvider#getParent(Object) */ public Object getParent(Object element) { if (element instanceof Segment) return fInput; return null; } /* * @see ITreeContentProvider#getChildren(Object) */ public Object[] getChildren(Object element) { if (element == fInput) return fContent.toArray(); return new Object[0]; } } protected Object fInput; protected IDocumentProvider fDocumentProvider; protected ITextEditor fTextEditor; /** * Creates a content outline page using the given provider and the given editor. * * @param provider the document provider * @param editor the editor */ public JavaContentOutlinePage(IDocumentProvider provider, ITextEditor editor) { super(); fDocumentProvider = provider; fTextEditor = editor; } /* (non-Javadoc) * Method declared on ContentOutlinePage */ public void createControl(Composite parent) { super.createControl(parent); TreeViewer viewer = getTreeViewer(); viewer.setContentProvider(new ContentProvider()); viewer.setLabelProvider(new LabelProvider()); viewer.addSelectionChangedListener(this); if (fInput != null) viewer.setInput(fInput); } /* (non-Javadoc) * Method declared on ContentOutlinePage */ public void selectionChanged(SelectionChangedEvent event) { super.selectionChanged(event); ISelection selection = event.getSelection(); if (selection.isEmpty()) fTextEditor.resetHighlightRange(); else { Segment segment = (Segment) ((IStructuredSelection) selection).getFirstElement(); int start = segment.position.getOffset(); int length = segment.position.getLength(); try { fTextEditor.setHighlightRange(start, length, true); } catch (IllegalArgumentException x) { fTextEditor.resetHighlightRange(); } } } /** * Sets the input of the outline page * * @param input the input of this outline page */ public void setInput(Object input) { fInput = input; update(); } /** * Updates the outline page. */ public void update() { TreeViewer viewer = getTreeViewer(); if (viewer != null) { Control control = viewer.getControl(); if (control != null && !control.isDisposed()) { control.setRedraw(false); viewer.setInput(fInput); viewer.expandAll(); control.setRedraw(true); } } } }