org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/text/template/contentassist/TemplateProposal.java - jdt/eclipse.jdt.ui - Git at Google

 /*******************************************************************************
  * Copyright (c) 2000, 2006 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.jdt.internal.ui.text.template.contentassist;

 import org.eclipse.core.runtime.Assert;
 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.IStatus;
 import org.eclipse.core.runtime.Status;

 import org.eclipse.swt.SWT;
 import org.eclipse.swt.graphics.Image;
 import org.eclipse.swt.graphics.Point;
 import org.eclipse.swt.widgets.Shell;

 import org.eclipse.jface.dialogs.MessageDialog;

 import org.eclipse.jface.text.BadLocationException;
 import org.eclipse.jface.text.BadPositionCategoryException;
 import org.eclipse.jface.text.DocumentEvent;
 import org.eclipse.jface.text.IDocument;
 import org.eclipse.jface.text.IInformationControlCreator;
 import org.eclipse.jface.text.IRegion;
 import org.eclipse.jface.text.ITextViewer;
 import org.eclipse.jface.text.Position;
 import org.eclipse.jface.text.Region;
 import org.eclipse.jface.text.contentassist.ICompletionProposal;
 import org.eclipse.jface.text.contentassist.ICompletionProposalExtension2;
 import org.eclipse.jface.text.contentassist.ICompletionProposalExtension3;
 import org.eclipse.jface.text.contentassist.ICompletionProposalExtension4;
 import org.eclipse.jface.text.contentassist.IContextInformation;
 import org.eclipse.jface.text.link.ILinkedModeListener;
 import org.eclipse.jface.text.link.LinkedModeModel;
 import org.eclipse.jface.text.link.LinkedModeUI;
 import org.eclipse.jface.text.link.LinkedPosition;
 import org.eclipse.jface.text.link.LinkedPositionGroup;
 import org.eclipse.jface.text.link.ProposalPosition;
 import org.eclipse.jface.text.templates.DocumentTemplateContext;
 import org.eclipse.jface.text.templates.GlobalTemplateVariables;
 import org.eclipse.jface.text.templates.Template;
 import org.eclipse.jface.text.templates.TemplateBuffer;
 import org.eclipse.jface.text.templates.TemplateContext;
 import org.eclipse.jface.text.templates.TemplateException;
 import org.eclipse.jface.text.templates.TemplateVariable;

 import org.eclipse.ui.IEditorPart;
 import org.eclipse.ui.part.IWorkbenchPartOrientation;
 import org.eclipse.ui.texteditor.link.EditorLinkedModeUI;

 import org.eclipse.jdt.internal.corext.template.java.CompilationUnitContext;
 import org.eclipse.jdt.internal.corext.template.java.JavaDocContext;
 import org.eclipse.jdt.internal.corext.util.Messages;

 import org.eclipse.jdt.ui.text.java.IJavaCompletionProposal;

 import org.eclipse.jdt.internal.ui.JavaPlugin;
 import org.eclipse.jdt.internal.ui.javaeditor.EditorHighlightingSynchronizer;
 import org.eclipse.jdt.internal.ui.javaeditor.JavaEditor;
 import org.eclipse.jdt.internal.ui.util.ExceptionHandler;

 /**
  * A template proposal.
  */
 public class TemplateProposal implements IJavaCompletionProposal, ICompletionProposalExtension2, ICompletionProposalExtension3, ICompletionProposalExtension4 {

 	private final Template fTemplate;
 	private final TemplateContext fContext;
 	private final Image fImage;
 	private IRegion fRegion;
 	private int fRelevance;

 	private IRegion fSelectedRegion; // initialized by apply()
 	private String fDisplayString;

 	/**
 	 * Creates a template proposal with a template and its context.
 	 *
 	 * @param template  the template
 	 * @param context   the context in which the template was requested
 	 * @param region 	the region this proposal applies to
 	 * @param image     the icon of the proposal
 	 */
 	public TemplateProposal(Template template, TemplateContext context, IRegion region, Image image) {
 		Assert.isNotNull(template);
 		Assert.isNotNull(context);
 		Assert.isNotNull(region);

 		fTemplate= template;
 		fContext= context;
 		fImage= image;
 		fRegion= region;

 		fDisplayString= null;

 		fRelevance= computeRelevance();
 	}

 	/**
 	 * Computes the relevance to match the relevance values generated by the
 	 * core content assistant.
 	 *
 	 * @return a sensible relevance value.
 	 */
 	private int computeRelevance() {
 		// see org.eclipse.jdt.internal.codeassist.RelevanceConstants
 		final int R_DEFAULT= 0;
 		final int R_INTERESTING= 5;
 		final int R_CASE= 10;
 		final int R_NON_RESTRICTED= 3;
 		final int R_EXACT_NAME = 4;
 		final int R_INLINE_TAG = 31;

 		int base= R_DEFAULT + R_INTERESTING + R_NON_RESTRICTED;

 		try {
 			if (fContext instanceof DocumentTemplateContext) {
 				DocumentTemplateContext templateContext= (DocumentTemplateContext) fContext;
 				IDocument document= templateContext.getDocument();

 				String content= document.get(fRegion.getOffset(), fRegion.getLength());
 				if (fTemplate.getName().startsWith(content))
 					base += R_CASE;
 				if (fTemplate.getName().equalsIgnoreCase(content))
 					base += R_EXACT_NAME;
 				if (fContext instanceof JavaDocContext)
 					base += R_INLINE_TAG;
 			}
 		} catch (BadLocationException e) {
 			// ignore - not a case sensitive match then
 		}

 		// see CompletionProposalCollector.computeRelevance
 		// just under keywords, but better than packages
 		final int TEMPLATE_RELEVANCE= 1;
 		return base * 16 + TEMPLATE_RELEVANCE;
 	}

 	/*
 	 * @see ICompletionProposal#apply(IDocument)
 	 */
 	public final void apply(IDocument document) {
 		// not called anymore
 	}

 	/*
 	 * @see org.eclipse.jface.text.contentassist.ICompletionProposalExtension2#apply(org.eclipse.jface.text.ITextViewer, char, int, int)
 	 */
 	public void apply(ITextViewer viewer, char trigger, int stateMask, int offset) {

 		try {

 			fContext.setReadOnly(false);
 			TemplateBuffer templateBuffer;
 			try {
 				templateBuffer= fContext.evaluate(fTemplate);
 			} catch (TemplateException e1) {
 				fSelectedRegion= fRegion;
 				return;
 			}

 			int start= getReplaceOffset();
 			int end= getReplaceEndOffset();
 			end= Math.max(end, offset);

 			// insert template string
 			IDocument document= viewer.getDocument();
 			if (end > document.getLength())
 				end= offset;
 			String templateString= templateBuffer.getString();
 			document.replace(start, end - start, templateString);

 			// translate positions
 			LinkedModeModel model= new LinkedModeModel();
 			TemplateVariable[] variables= templateBuffer.getVariables();

 			MultiVariableGuess guess= fContext instanceof CompilationUnitContext ? ((CompilationUnitContext) fContext).getMultiVariableGuess() : null;

 			boolean hasPositions= false;
 			for (int i= 0; i != variables.length; i++) {
 				TemplateVariable variable= variables[i];

 				if (variable.isUnambiguous())
 					continue;

 				LinkedPositionGroup group= new LinkedPositionGroup();

 				int[] offsets= variable.getOffsets();
 				int length= variable.getLength();

 				LinkedPosition first;
 				if (guess != null && variable instanceof MultiVariable) {
 					first= new VariablePosition(document, offsets[0] + start, length, guess, (MultiVariable) variable);
 					guess.addSlave((VariablePosition) first);
 				} else {
 					String[] values= variable.getValues();
 					ICompletionProposal[] proposals= new ICompletionProposal[values.length];
 					for (int j= 0; j < values.length; j++) {
 						ensurePositionCategoryInstalled(document, model);
 						Position pos= new Position(offsets[0] + start, length);
 						document.addPosition(getCategory(), pos);
 						proposals[j]= new PositionBasedCompletionProposal(values[j], pos, length);
 					}

 					if (proposals.length > 1)
 						first= new ProposalPosition(document, offsets[0] + start, length, proposals);
 					else
 						first= new LinkedPosition(document, offsets[0] + start, length);
 				}

 				for (int j= 0; j != offsets.length; j++)
 					if (j == 0)
 						group.addPosition(first);
 					else
 						group.addPosition(new LinkedPosition(document, offsets[j] + start, length));

 				model.addGroup(group);
 				hasPositions= true;
 			}

 			if (hasPositions) {
 				model.forceInstall();
 				JavaEditor editor= getJavaEditor();
 				if (editor != null) {
 					model.addLinkingListener(new EditorHighlightingSynchronizer(editor));
 				}

 				LinkedModeUI ui= new EditorLinkedModeUI(model, viewer);
 				ui.setExitPosition(viewer, getCaretOffset(templateBuffer) + start, 0, Integer.MAX_VALUE);
 				ui.enter();

 				fSelectedRegion= ui.getSelectedRegion();
 			} else
 				fSelectedRegion= new Region(getCaretOffset(templateBuffer) + start, 0);

 		} catch (BadLocationException e) {
 			JavaPlugin.log(e);
 			openErrorDialog(viewer.getTextWidget().getShell(), e);
 			fSelectedRegion= fRegion;
 		} catch (BadPositionCategoryException e) {
 			JavaPlugin.log(e);
 			openErrorDialog(viewer.getTextWidget().getShell(), e);
 			fSelectedRegion= fRegion;
 		}

 	}

 	/**
 	 * Returns the currently active java editor, or <code>null</code> if it
 	 * cannot be determined.
 	 *
 	 * @return  the currently active java editor, or <code>null</code>
 	 */
 	private JavaEditor getJavaEditor() {
 		IEditorPart part= JavaPlugin.getActivePage().getActiveEditor();
 		if (part instanceof JavaEditor)
 			return (JavaEditor) part;
 		else
 			return null;
 	}

 	/**
 	 * Returns the offset of the range in the document that will be replaced by
 	 * applying this template.
 	 *
 	 * @return the offset of the range in the document that will be replaced by
 	 *         applying this template
 	 */
 	private int getReplaceOffset() {
 		int start;
 		if (fContext instanceof DocumentTemplateContext) {
 			DocumentTemplateContext docContext = (DocumentTemplateContext)fContext;
 			start= docContext.getStart();
 		} else {
 			start= fRegion.getOffset();
 		}
 		return start;
 	}

 	/**
 	 * Returns the end offset of the range in the document that will be replaced
 	 * by applying this template.
 	 *
 	 * @return the end offset of the range in the document that will be replaced
 	 *         by applying this template
 	 */
 	private int getReplaceEndOffset() {
 		int end;
 		if (fContext instanceof DocumentTemplateContext) {
 			DocumentTemplateContext docContext = (DocumentTemplateContext)fContext;
 			end= docContext.getEnd();
 		} else {
 			end= fRegion.getOffset() + fRegion.getLength();
 		}
 		return end;
 	}

 	private void ensurePositionCategoryInstalled(final IDocument document, LinkedModeModel model) {
 		if (!document.containsPositionCategory(getCategory())) {
 			document.addPositionCategory(getCategory());
 			final InclusivePositionUpdater updater= new InclusivePositionUpdater(getCategory());
 			document.addPositionUpdater(updater);

 			model.addLinkingListener(new ILinkedModeListener() {

 				/*
 				 * @see org.eclipse.jface.text.link.ILinkedModeListener#left(org.eclipse.jface.text.link.LinkedModeModel, int)
 				 */
 				public void left(LinkedModeModel environment, int flags) {
 					try {
 						document.removePositionCategory(getCategory());
 					} catch (BadPositionCategoryException e) {
 						// ignore
 					}
 					document.removePositionUpdater(updater);
 				}

 				public void suspend(LinkedModeModel environment) {}
 				public void resume(LinkedModeModel environment, int flags) {}
 			});
 		}
 	}

 	private String getCategory() {
 		return "TemplateProposalCategory_" + toString(); //$NON-NLS-1$
 	}

 	private int getCaretOffset(TemplateBuffer buffer) {

 	    TemplateVariable[] variables= buffer.getVariables();
 		for (int i= 0; i != variables.length; i++) {
 			TemplateVariable variable= variables[i];
 			if (variable.getType().equals(GlobalTemplateVariables.Cursor.NAME))
 				return variable.getOffsets()[0];
 		}

 		return buffer.getString().length();
 	}

 	/*
 	 * @see ICompletionProposal#getSelection(IDocument)
 	 */
 	public Point getSelection(IDocument document) {
 		return new Point(fSelectedRegion.getOffset(), fSelectedRegion.getLength());
 	}

 	/*
 	 * @see ICompletionProposal#getAdditionalProposalInfo()
 	 */
 	public String getAdditionalProposalInfo() {
 	    try {
 		    fContext.setReadOnly(true);
 			TemplateBuffer templateBuffer;
 			try {
 				templateBuffer= fContext.evaluate(fTemplate);
 			} catch (TemplateException e1) {
 				return null;
 			}

 			return templateBuffer.getString();

 	    } catch (BadLocationException e) {
 			handleException(JavaPlugin.getActiveWorkbenchShell(), new CoreException(new Status(IStatus.ERROR, JavaPlugin.getPluginId(), IStatus.OK, "", e))); //$NON-NLS-1$
 			return null;
 		}
 	}

 	/*
 	 * @see ICompletionProposal#getDisplayString()
 	 */
 	public String getDisplayString() {
 		if (fDisplayString == null) {
 			String[] arguments= new String[] { fTemplate.getName(), fTemplate.getDescription() };
 			fDisplayString= Messages.format(TemplateContentAssistMessages.TemplateProposal_displayString, arguments);
 		}
 		return fDisplayString;
 	}

 	public void setDisplayString(String displayString) {
 		fDisplayString= displayString;
 	}

 	/*
 	 * @see ICompletionProposal#getImage()
 	 */
 	public Image getImage() {
 		return fImage;
 	}

 	/*
 	 * @see ICompletionProposal#getContextInformation()
 	 */
 	public IContextInformation getContextInformation() {
 		return null;
 	}

 	private void openErrorDialog(Shell shell, Exception e) {
 		MessageDialog.openError(shell, TemplateContentAssistMessages.TemplateEvaluator_error_title, e.getMessage());
 	}

 	private void handleException(Shell shell, CoreException e) {
 		ExceptionHandler.handle(e, shell, TemplateContentAssistMessages.TemplateEvaluator_error_title, null);
 	}

 	/*
 	 * @see IJavaCompletionProposal#getRelevance()
 	 */
 	public int getRelevance() {
 		return fRelevance;
 	}

 	public void setRelevance(int relevance) {
 		fRelevance= relevance;
 	}

 	public Template getTemplate() {
 		return fTemplate;
 	}

 	/*
 	 * @see org.eclipse.jface.text.contentassist.ICompletionProposalExtension3#getInformationControlCreator()
 	 */
 	public IInformationControlCreator getInformationControlCreator() {
 		int orientation;
 		IEditorPart editor= getJavaEditor();
 		if (editor instanceof IWorkbenchPartOrientation)
 			orientation= ((IWorkbenchPartOrientation)editor).getOrientation();
 		else
 			orientation= SWT.LEFT_TO_RIGHT;
 		return new TemplateInformationControlCreator(orientation);
 	}

 	/*
 	 * @see org.eclipse.jface.text.contentassist.ICompletionProposalExtension2#selected(org.eclipse.jface.text.ITextViewer, boolean)
 	 */
 	public void selected(ITextViewer viewer, boolean smartToggle) {
 	}

 	/*
 	 * @see org.eclipse.jface.text.contentassist.ICompletionProposalExtension2#unselected(org.eclipse.jface.text.ITextViewer)
 	 */
 	public void unselected(ITextViewer viewer) {
 	}

 	/*
 	 * @see org.eclipse.jface.text.contentassist.ICompletionProposalExtension2#validate(org.eclipse.jface.text.IDocument, int, org.eclipse.jface.text.DocumentEvent)
 	 */
 	public boolean validate(IDocument document, int offset, DocumentEvent event) {
 		try {
 			int replaceOffset= getReplaceOffset();
 			if (offset >= replaceOffset) {
 				String content= document.get(replaceOffset, offset - replaceOffset);
 				String templateName= fTemplate.getName().toLowerCase();
 				boolean valid= templateName.startsWith(content.toLowerCase());
 				if (!valid && fContext instanceof JavaDocContext && templateName.startsWith("<")) { //$NON-NLS-1$
 					valid= templateName.startsWith(content.toLowerCase(), 1);
 				}
 				return valid;
 			}
 		} catch (BadLocationException e) {
 			// concurrent modification - ignore
 		}
 		return false;
 	}

 	/*
 	 * @see org.eclipse.jface.text.contentassist.ICompletionProposalExtension3#getReplacementString()
 	 */
 	public CharSequence getPrefixCompletionText(IDocument document, int completionOffset) {
 		// bug 114360 - don't make selection templates prefix-completable
 		if (isSelectionTemplate())
 			return ""; //$NON-NLS-1$
 		return fTemplate.getName();
 	}

 	/*
 	 * @see org.eclipse.jface.text.contentassist.ICompletionProposalExtension3#getReplacementOffset()
 	 */
 	public int getPrefixCompletionStart(IDocument document, int completionOffset) {
 		return getReplaceOffset();
 	}

 	/*
 	 * @see org.eclipse.jface.text.contentassist.ICompletionProposalExtension4#isAutoInsertable()
 	 */
 	public boolean isAutoInsertable() {
 		if (isSelectionTemplate())
 			return false;
 		return fTemplate.isAutoInsertable();
 	}

 	/**
 	 * Returns <code>true</code> if the proposal has a selection, e.g. will wrap some code.
 	 *
 	 * @return <code>true</code> if the proposals completion length is non zero
 	 * @since 3.2
 	 */
 	private boolean isSelectionTemplate() {
 		if (fContext instanceof DocumentTemplateContext) {
 			DocumentTemplateContext ctx= (DocumentTemplateContext) fContext;
 			if (ctx.getCompletionLength() > 0)
 				return true;
 		}
 		return false;
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2000, 2006 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.jdt.internal.ui.text.template.contentassist;

	import org.eclipse.core.runtime.Assert;
	import org.eclipse.core.runtime.CoreException;
	import org.eclipse.core.runtime.IStatus;
	import org.eclipse.core.runtime.Status;

	import org.eclipse.swt.SWT;
	import org.eclipse.swt.graphics.Image;
	import org.eclipse.swt.graphics.Point;
	import org.eclipse.swt.widgets.Shell;

	import org.eclipse.jface.dialogs.MessageDialog;

	import org.eclipse.jface.text.BadLocationException;
	import org.eclipse.jface.text.BadPositionCategoryException;
	import org.eclipse.jface.text.DocumentEvent;
	import org.eclipse.jface.text.IDocument;
	import org.eclipse.jface.text.IInformationControlCreator;
	import org.eclipse.jface.text.IRegion;
	import org.eclipse.jface.text.ITextViewer;
	import org.eclipse.jface.text.Position;
	import org.eclipse.jface.text.Region;
	import org.eclipse.jface.text.contentassist.ICompletionProposal;
	import org.eclipse.jface.text.contentassist.ICompletionProposalExtension2;
	import org.eclipse.jface.text.contentassist.ICompletionProposalExtension3;
	import org.eclipse.jface.text.contentassist.ICompletionProposalExtension4;
	import org.eclipse.jface.text.contentassist.IContextInformation;
	import org.eclipse.jface.text.link.ILinkedModeListener;
	import org.eclipse.jface.text.link.LinkedModeModel;
	import org.eclipse.jface.text.link.LinkedModeUI;
	import org.eclipse.jface.text.link.LinkedPosition;
	import org.eclipse.jface.text.link.LinkedPositionGroup;
	import org.eclipse.jface.text.link.ProposalPosition;
	import org.eclipse.jface.text.templates.DocumentTemplateContext;
	import org.eclipse.jface.text.templates.GlobalTemplateVariables;
	import org.eclipse.jface.text.templates.Template;
	import org.eclipse.jface.text.templates.TemplateBuffer;
	import org.eclipse.jface.text.templates.TemplateContext;
	import org.eclipse.jface.text.templates.TemplateException;
	import org.eclipse.jface.text.templates.TemplateVariable;

	import org.eclipse.ui.IEditorPart;
	import org.eclipse.ui.part.IWorkbenchPartOrientation;
	import org.eclipse.ui.texteditor.link.EditorLinkedModeUI;

	import org.eclipse.jdt.internal.corext.template.java.CompilationUnitContext;
	import org.eclipse.jdt.internal.corext.template.java.JavaDocContext;
	import org.eclipse.jdt.internal.corext.util.Messages;

	import org.eclipse.jdt.ui.text.java.IJavaCompletionProposal;

	import org.eclipse.jdt.internal.ui.JavaPlugin;
	import org.eclipse.jdt.internal.ui.javaeditor.EditorHighlightingSynchronizer;
	import org.eclipse.jdt.internal.ui.javaeditor.JavaEditor;
	import org.eclipse.jdt.internal.ui.util.ExceptionHandler;

	/**
	* A template proposal.
	*/
	public class TemplateProposal implements IJavaCompletionProposal, ICompletionProposalExtension2, ICompletionProposalExtension3, ICompletionProposalExtension4 {

	private final Template fTemplate;
	private final TemplateContext fContext;
	private final Image fImage;
	private IRegion fRegion;
	private int fRelevance;

	private IRegion fSelectedRegion; // initialized by apply()
	private String fDisplayString;

	/**
	* Creates a template proposal with a template and its context.
	*
	* @param template the template
	* @param context the context in which the template was requested
	* @param region the region this proposal applies to
	* @param image the icon of the proposal
	*/
	public TemplateProposal(Template template, TemplateContext context, IRegion region, Image image) {
	Assert.isNotNull(template);
	Assert.isNotNull(context);
	Assert.isNotNull(region);

	fTemplate= template;
	fContext= context;
	fImage= image;
	fRegion= region;

	fDisplayString= null;

	fRelevance= computeRelevance();
	}

	/**
	* Computes the relevance to match the relevance values generated by the
	* core content assistant.
	*
	* @return a sensible relevance value.
	*/
	private int computeRelevance() {
	// see org.eclipse.jdt.internal.codeassist.RelevanceConstants
	final int R_DEFAULT= 0;
	final int R_INTERESTING= 5;
	final int R_CASE= 10;
	final int R_NON_RESTRICTED= 3;
	final int R_EXACT_NAME = 4;
	final int R_INLINE_TAG = 31;

	int base= R_DEFAULT + R_INTERESTING + R_NON_RESTRICTED;

	try {
	if (fContext instanceof DocumentTemplateContext) {
	DocumentTemplateContext templateContext= (DocumentTemplateContext) fContext;
	IDocument document= templateContext.getDocument();

	String content= document.get(fRegion.getOffset(), fRegion.getLength());
	if (fTemplate.getName().startsWith(content))
	base += R_CASE;
	if (fTemplate.getName().equalsIgnoreCase(content))
	base += R_EXACT_NAME;
	if (fContext instanceof JavaDocContext)
	base += R_INLINE_TAG;
	}
	} catch (BadLocationException e) {
	// ignore - not a case sensitive match then
	}

	// see CompletionProposalCollector.computeRelevance
	// just under keywords, but better than packages
	final int TEMPLATE_RELEVANCE= 1;
	return base * 16 + TEMPLATE_RELEVANCE;
	}

	/*
	* @see ICompletionProposal#apply(IDocument)
	*/
	public final void apply(IDocument document) {
	// not called anymore
	}

	/*
	* @see org.eclipse.jface.text.contentassist.ICompletionProposalExtension2#apply(org.eclipse.jface.text.ITextViewer, char, int, int)
	*/
	public void apply(ITextViewer viewer, char trigger, int stateMask, int offset) {

	try {

	fContext.setReadOnly(false);
	TemplateBuffer templateBuffer;
	try {
	templateBuffer= fContext.evaluate(fTemplate);
	} catch (TemplateException e1) {
	fSelectedRegion= fRegion;
	return;
	}

	int start= getReplaceOffset();
	int end= getReplaceEndOffset();
	end= Math.max(end, offset);

	// insert template string
	IDocument document= viewer.getDocument();
	if (end > document.getLength())
	end= offset;
	String templateString= templateBuffer.getString();
	document.replace(start, end - start, templateString);

	// translate positions
	LinkedModeModel model= new LinkedModeModel();
	TemplateVariable[] variables= templateBuffer.getVariables();

	MultiVariableGuess guess= fContext instanceof CompilationUnitContext ? ((CompilationUnitContext) fContext).getMultiVariableGuess() : null;

	boolean hasPositions= false;
	for (int i= 0; i != variables.length; i++) {
	TemplateVariable variable= variables[i];

	if (variable.isUnambiguous())
	continue;

	LinkedPositionGroup group= new LinkedPositionGroup();

	int[] offsets= variable.getOffsets();
	int length= variable.getLength();

	LinkedPosition first;
	if (guess != null && variable instanceof MultiVariable) {
	first= new VariablePosition(document, offsets[0] + start, length, guess, (MultiVariable) variable);
	guess.addSlave((VariablePosition) first);
	} else {
	String[] values= variable.getValues();
	ICompletionProposal[] proposals= new ICompletionProposal[values.length];
	for (int j= 0; j < values.length; j++) {
	ensurePositionCategoryInstalled(document, model);
	Position pos= new Position(offsets[0] + start, length);
	document.addPosition(getCategory(), pos);
	proposals[j]= new PositionBasedCompletionProposal(values[j], pos, length);
	}

	if (proposals.length > 1)
	first= new ProposalPosition(document, offsets[0] + start, length, proposals);
	else
	first= new LinkedPosition(document, offsets[0] + start, length);
	}

	for (int j= 0; j != offsets.length; j++)
	if (j == 0)
	group.addPosition(first);
	else
	group.addPosition(new LinkedPosition(document, offsets[j] + start, length));

	model.addGroup(group);
	hasPositions= true;
	}

	if (hasPositions) {
	model.forceInstall();
	JavaEditor editor= getJavaEditor();
	if (editor != null) {
	model.addLinkingListener(new EditorHighlightingSynchronizer(editor));
	}

	LinkedModeUI ui= new EditorLinkedModeUI(model, viewer);
	ui.setExitPosition(viewer, getCaretOffset(templateBuffer) + start, 0, Integer.MAX_VALUE);
	ui.enter();

	fSelectedRegion= ui.getSelectedRegion();
	} else
	fSelectedRegion= new Region(getCaretOffset(templateBuffer) + start, 0);

	} catch (BadLocationException e) {
	JavaPlugin.log(e);
	openErrorDialog(viewer.getTextWidget().getShell(), e);
	fSelectedRegion= fRegion;
	} catch (BadPositionCategoryException e) {
	JavaPlugin.log(e);
	openErrorDialog(viewer.getTextWidget().getShell(), e);
	fSelectedRegion= fRegion;
	}

	}

	/**
	* Returns the currently active java editor, or <code>null</code> if it
	* cannot be determined.
	*
	* @return the currently active java editor, or <code>null</code>
	*/
	private JavaEditor getJavaEditor() {
	IEditorPart part= JavaPlugin.getActivePage().getActiveEditor();
	if (part instanceof JavaEditor)
	return (JavaEditor) part;
	else
	return null;
	}

	/**
	* Returns the offset of the range in the document that will be replaced by
	* applying this template.
	*
	* @return the offset of the range in the document that will be replaced by
	* applying this template
	*/
	private int getReplaceOffset() {
	int start;
	if (fContext instanceof DocumentTemplateContext) {
	DocumentTemplateContext docContext = (DocumentTemplateContext)fContext;
	start= docContext.getStart();
	} else {
	start= fRegion.getOffset();
	}
	return start;
	}

	/**
	* Returns the end offset of the range in the document that will be replaced
	* by applying this template.
	*
	* @return the end offset of the range in the document that will be replaced
	* by applying this template
	*/
	private int getReplaceEndOffset() {
	int end;
	if (fContext instanceof DocumentTemplateContext) {
	DocumentTemplateContext docContext = (DocumentTemplateContext)fContext;
	end= docContext.getEnd();
	} else {
	end= fRegion.getOffset() + fRegion.getLength();
	}
	return end;
	}

	private void ensurePositionCategoryInstalled(final IDocument document, LinkedModeModel model) {
	if (!document.containsPositionCategory(getCategory())) {
	document.addPositionCategory(getCategory());
	final InclusivePositionUpdater updater= new InclusivePositionUpdater(getCategory());
	document.addPositionUpdater(updater);

	model.addLinkingListener(new ILinkedModeListener() {

	/*
	* @see org.eclipse.jface.text.link.ILinkedModeListener#left(org.eclipse.jface.text.link.LinkedModeModel, int)
	*/
	public void left(LinkedModeModel environment, int flags) {
	try {
	document.removePositionCategory(getCategory());
	} catch (BadPositionCategoryException e) {
	// ignore
	}
	document.removePositionUpdater(updater);
	}

	public void suspend(LinkedModeModel environment) {}
	public void resume(LinkedModeModel environment, int flags) {}
	});
	}
	}

	private String getCategory() {
	return "TemplateProposalCategory_" + toString(); //$NON-NLS-1$
	}

	private int getCaretOffset(TemplateBuffer buffer) {

	TemplateVariable[] variables= buffer.getVariables();
	for (int i= 0; i != variables.length; i++) {
	TemplateVariable variable= variables[i];
	if (variable.getType().equals(GlobalTemplateVariables.Cursor.NAME))
	return variable.getOffsets()[0];
	}

	return buffer.getString().length();
	}

	/*
	* @see ICompletionProposal#getSelection(IDocument)
	*/
	public Point getSelection(IDocument document) {
	return new Point(fSelectedRegion.getOffset(), fSelectedRegion.getLength());
	}

	/*
	* @see ICompletionProposal#getAdditionalProposalInfo()
	*/
	public String getAdditionalProposalInfo() {
	try {
	fContext.setReadOnly(true);
	TemplateBuffer templateBuffer;
	try {
	templateBuffer= fContext.evaluate(fTemplate);
	} catch (TemplateException e1) {
	return null;
	}

	return templateBuffer.getString();

	} catch (BadLocationException e) {
	handleException(JavaPlugin.getActiveWorkbenchShell(), new CoreException(new Status(IStatus.ERROR, JavaPlugin.getPluginId(), IStatus.OK, "", e))); //$NON-NLS-1$
	return null;
	}
	}

	/*
	* @see ICompletionProposal#getDisplayString()
	*/
	public String getDisplayString() {
	if (fDisplayString == null) {
	String[] arguments= new String[] { fTemplate.getName(), fTemplate.getDescription() };
	fDisplayString= Messages.format(TemplateContentAssistMessages.TemplateProposal_displayString, arguments);
	}
	return fDisplayString;
	}

	public void setDisplayString(String displayString) {
	fDisplayString= displayString;
	}

	/*
	* @see ICompletionProposal#getImage()
	*/
	public Image getImage() {
	return fImage;
	}

	/*
	* @see ICompletionProposal#getContextInformation()
	*/
	public IContextInformation getContextInformation() {
	return null;
	}

	private void openErrorDialog(Shell shell, Exception e) {
	MessageDialog.openError(shell, TemplateContentAssistMessages.TemplateEvaluator_error_title, e.getMessage());
	}

	private void handleException(Shell shell, CoreException e) {
	ExceptionHandler.handle(e, shell, TemplateContentAssistMessages.TemplateEvaluator_error_title, null);
	}

	/*
	* @see IJavaCompletionProposal#getRelevance()
	*/
	public int getRelevance() {
	return fRelevance;
	}

	public void setRelevance(int relevance) {
	fRelevance= relevance;
	}

	public Template getTemplate() {
	return fTemplate;
	}

	/*
	* @see org.eclipse.jface.text.contentassist.ICompletionProposalExtension3#getInformationControlCreator()
	*/
	public IInformationControlCreator getInformationControlCreator() {
	int orientation;
	IEditorPart editor= getJavaEditor();
	if (editor instanceof IWorkbenchPartOrientation)
	orientation= ((IWorkbenchPartOrientation)editor).getOrientation();
	else
	orientation= SWT.LEFT_TO_RIGHT;
	return new TemplateInformationControlCreator(orientation);
	}

	/*
	* @see org.eclipse.jface.text.contentassist.ICompletionProposalExtension2#selected(org.eclipse.jface.text.ITextViewer, boolean)
	*/
	public void selected(ITextViewer viewer, boolean smartToggle) {
	}

	/*
	* @see org.eclipse.jface.text.contentassist.ICompletionProposalExtension2#unselected(org.eclipse.jface.text.ITextViewer)
	*/
	public void unselected(ITextViewer viewer) {
	}

	/*
	* @see org.eclipse.jface.text.contentassist.ICompletionProposalExtension2#validate(org.eclipse.jface.text.IDocument, int, org.eclipse.jface.text.DocumentEvent)
	*/
	public boolean validate(IDocument document, int offset, DocumentEvent event) {
	try {
	int replaceOffset= getReplaceOffset();
	if (offset >= replaceOffset) {
	String content= document.get(replaceOffset, offset - replaceOffset);
	String templateName= fTemplate.getName().toLowerCase();
	boolean valid= templateName.startsWith(content.toLowerCase());
	if (!valid && fContext instanceof JavaDocContext && templateName.startsWith("<")) { //$NON-NLS-1$
	valid= templateName.startsWith(content.toLowerCase(), 1);
	}
	return valid;
	}
	} catch (BadLocationException e) {
	// concurrent modification - ignore
	}
	return false;
	}

	/*
	* @see org.eclipse.jface.text.contentassist.ICompletionProposalExtension3#getReplacementString()
	*/
	public CharSequence getPrefixCompletionText(IDocument document, int completionOffset) {
	// bug 114360 - don't make selection templates prefix-completable
	if (isSelectionTemplate())
	return ""; //$NON-NLS-1$
	return fTemplate.getName();
	}

	/*
	* @see org.eclipse.jface.text.contentassist.ICompletionProposalExtension3#getReplacementOffset()
	*/
	public int getPrefixCompletionStart(IDocument document, int completionOffset) {
	return getReplaceOffset();
	}

	/*
	* @see org.eclipse.jface.text.contentassist.ICompletionProposalExtension4#isAutoInsertable()
	*/
	public boolean isAutoInsertable() {
	if (isSelectionTemplate())
	return false;
	return fTemplate.isAutoInsertable();
	}

	/**
	* Returns <code>true</code> if the proposal has a selection, e.g. will wrap some code.
	*
	* @return <code>true</code> if the proposals completion length is non zero
	* @since 3.2
	*/
	private boolean isSelectionTemplate() {
	if (fContext instanceof DocumentTemplateContext) {
	DocumentTemplateContext ctx= (DocumentTemplateContext) fContext;
	if (ctx.getCompletionLength() > 0)
	return true;
	}
	return false;
	}
	}