org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/text/java/JavaCompletionProcessor.java - jdt/eclipse.jdt.ui - Git at Google

 /*******************************************************************************
  * Copyright (c) 2000, 2003 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Common Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/cpl-v10.html
  *
  * Contributors:
  *     IBM Corporation - initial API and implementation
  *******************************************************************************/
 package org.eclipse.jdt.internal.ui.text.java;


 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Hashtable;
 import java.util.List;

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

 import org.eclipse.jface.dialogs.ErrorDialog;
 import org.eclipse.jface.dialogs.MessageDialog;
 import org.eclipse.jface.text.IDocument;
 import org.eclipse.jface.text.ITextViewer;
 import org.eclipse.jface.text.contentassist.ICompletionProposal;
 import org.eclipse.jface.text.contentassist.IContentAssistProcessor;
 import org.eclipse.jface.text.contentassist.IContextInformation;
 import org.eclipse.jface.text.contentassist.IContextInformationExtension;
 import org.eclipse.jface.text.contentassist.IContextInformationValidator;

 import org.eclipse.ui.IEditorPart;

 import org.eclipse.jdt.core.ICompilationUnit;
 import org.eclipse.jdt.core.JavaCore;
 import org.eclipse.jdt.core.JavaModelException;

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

 import org.eclipse.jdt.internal.corext.template.ContextType;
 import org.eclipse.jdt.internal.corext.template.ContextTypeRegistry;

 import org.eclipse.jdt.internal.ui.JavaPlugin;
 import org.eclipse.jdt.internal.ui.JavaUIMessages;
 import org.eclipse.jdt.internal.ui.text.JavaCodeReader;
 import org.eclipse.jdt.internal.ui.text.template.TemplateEngine;
 import org.eclipse.jdt.internal.ui.text.template.TemplateProposal;


 /**
  * Java completion processor.
  */
 public class JavaCompletionProcessor implements IContentAssistProcessor {

 	private static class ContextInformationWrapper implements IContextInformation, IContextInformationExtension {

 		private final IContextInformation fContextInformation;
 		private int fPosition;

 		public ContextInformationWrapper(IContextInformation contextInformation) {
 			fContextInformation= contextInformation;
 		}

 		/*
 		 * @see IContextInformation#getContextDisplayString()
 		 */
 		public String getContextDisplayString() {
 			return fContextInformation.getContextDisplayString();
 		}

 			/*
 		 * @see IContextInformation#getImage()
 		 */
 		public Image getImage() {
 			return fContextInformation.getImage();
 		}

 		/*
 		 * @see IContextInformation#getInformationDisplayString()
 		 */
 		public String getInformationDisplayString() {
 			return fContextInformation.getInformationDisplayString();
 		}

 		/*
 		 * @see IContextInformationExtension#getContextInformationPosition()
 		 */
 		public int getContextInformationPosition() {
 			return fPosition;
 		}

 		public void setContextInformationPosition(int position) {
 			fPosition= position;
 		}

 		/*
 		 * @see org.eclipse.jface.text.contentassist.IContextInformation#equals(java.lang.Object)
 		 */
 		public boolean equals(Object object) {
 			if (object instanceof ContextInformationWrapper)
 				return fContextInformation.equals(((ContextInformationWrapper) object).fContextInformation);
 			else
 				return fContextInformation.equals(object);
 		}
 	}


 	private final static String VISIBILITY= JavaCore.CODEASSIST_VISIBILITY_CHECK;
 	private final static String ENABLED= "enabled"; //$NON-NLS-1$
 	private final static String DISABLED= "disabled"; //$NON-NLS-1$


 	protected IWorkingCopyManager fManager;
 	private IEditorPart fEditor;
 	private ResultCollector fCollector;
 	private IContextInformationValidator fValidator;

 	private char[] fProposalAutoActivationSet;
 	private JavaCompletionProposalComparator fComparator;
 	private boolean fAllowAddImports;

 	private TemplateEngine fTemplateEngine;
 	private ExperimentalResultCollector fExperimentalCollector;

 	private int fNumberOfComputedResults= 0;


 	public JavaCompletionProcessor(IEditorPart editor) {
 		fEditor= editor;
 		fCollector= new ResultCollector();
 		fManager= JavaPlugin.getDefault().getWorkingCopyManager();
 		ContextType contextType= ContextTypeRegistry.getInstance().getContextType("java"); //$NON-NLS-1$
 		if (contextType != null)
 			fTemplateEngine= new TemplateEngine(contextType);
 		fExperimentalCollector= new ExperimentalResultCollector();
 		fAllowAddImports= true;

 		fComparator= new JavaCompletionProposalComparator();
 	}

 	/**
 	 * Sets this processor's set of characters triggering the activation of the
 	 * completion proposal computation.
 	 *
 	 * @param activationSet the activation set
 	 */
 	public void setCompletionProposalAutoActivationCharacters(char[] activationSet) {
 		fProposalAutoActivationSet= activationSet;
 	}

 	/**
 	 * Tells this processor to restrict its proposal to those element
 	 * visible in the actual invocation context.
 	 *
 	 * @param restrict <code>true</code> if proposals should be restricted
 	 */
 	public void restrictProposalsToVisibility(boolean restrict) {
 		Hashtable options= JavaCore.getOptions();
 		Object value= options.get(VISIBILITY);
 		if (value instanceof String) {
 			String newValue= restrict ? ENABLED : DISABLED;
 			if ( !newValue.equals(value)) {
 				options.put(VISIBILITY, newValue);
 				JavaCore.setOptions(options);
 			}
 		}
 	}

 	/**
 	 * Tells this processor to order the proposals alphabetically.
 	 *
 	 * @param order <code>true</code> if proposals should be ordered.
 	 */
 	public void orderProposalsAlphabetically(boolean order) {
 		fComparator.setOrderAlphabetically(order);
 	}

 	/**
 	 * Tells this processor to restrict is proposals to those
 	 * starting with matching cases.
 	 *
 	 * @param restrict <code>true</code> if proposals should be restricted
 	 */
 	public void restrictProposalsToMatchingCases(boolean restrict) {
 		// not yet supported
 	}

 	/**
 	 * Tells this processor to add import statement for proposals that have
 	 * a fully qualified type name
 	 *
 	 * @param restrict <code>true</code> if import can be added
 	 */
 	public void allowAddingImports(boolean allowAddingImports) {
 		fAllowAddImports= allowAddingImports;
 	}

 	/**
 	 * @see IContentAssistProcessor#getErrorMessage()
 	 */
 	public String getErrorMessage() {

 		if (fNumberOfComputedResults == 0) {
 			String errorMsg= fCollector.getErrorMessage();
 			if (errorMsg == null || errorMsg.trim().length() == 0)
 				errorMsg= JavaUIMessages.getString("JavaEditor.codeassist.noCompletions"); //$NON-NLS-1$
 			return errorMsg;
 		}

 		if (PreferenceConstants.getPreferenceStore().getBoolean(PreferenceConstants.CODEASSIST_FILL_ARGUMENT_NAMES))
 			return fExperimentalCollector.getErrorMessage();

 		return fCollector.getErrorMessage();
 	}

 	/**
 	 * @see IContentAssistProcessor#getContextInformationValidator()
 	 */
 	public IContextInformationValidator getContextInformationValidator() {
 		if (fValidator == null)
 			fValidator= new JavaParameterListValidator();
 		return fValidator;
 	}

 	/**
 	 * @see IContentAssistProcessor#getContextInformationAutoActivationCharacters()
 	 */
 	public char[] getContextInformationAutoActivationCharacters() {
 		return null;
 	}

 	/**
 	 * @see IContentAssistProcessor#getCompletionProposalAutoActivationCharacters()
 	 */
 	public char[] getCompletionProposalAutoActivationCharacters() {
 		return fProposalAutoActivationSet;
 	}

 	private boolean looksLikeMethod(JavaCodeReader reader) throws IOException {
 		int curr= reader.read();
 		while (curr != JavaCodeReader.EOF && Character.isWhitespace((char) curr))
 			curr= reader.read();

 		if (curr == JavaCodeReader.EOF)
 			return false;

 		return Character.isJavaIdentifierPart((char) curr) || Character.isJavaIdentifierStart((char) curr);
 	}

 	private int guessContextInformationPosition(ITextViewer viewer, int offset) {
 		int contextPosition= offset;

 		IDocument document= viewer.getDocument();

 		try {

 			JavaCodeReader reader= new JavaCodeReader();
 			reader.configureBackwardReader(document, offset, true, true);

 			int nestingLevel= 0;

 			int curr= reader.read();
 			while (curr != JavaCodeReader.EOF) {

 				if (')' == (char) curr)
 					++ nestingLevel;

 				else if ('(' == (char) curr) {
 					-- nestingLevel;

 					if (nestingLevel < 0) {
 						int start= reader.getOffset();
 						if (looksLikeMethod(reader))
 							return start + 1;
 					}
 				}

 				curr= reader.read();
 			}
 		} catch (IOException e) {
 		}

 		return contextPosition;
 	}

 	private List addContextInformations(ITextViewer viewer, int offset) {
 		ICompletionProposal[] proposals= internalComputeCompletionProposals(viewer, offset, -1);

 		List result= new ArrayList();
 		for (int i= 0; i < proposals.length; i++) {
 			IContextInformation contextInformation= proposals[i].getContextInformation();
 			if (contextInformation != null) {
 				ContextInformationWrapper wrapper= new ContextInformationWrapper(contextInformation);
 				wrapper.setContextInformationPosition(offset);
 				result.add(wrapper);
 			}
 		}
 		return result;
 	}

 	/**
 	 * @see IContentAssistProcessor#computeContextInformation(ITextViewer, int)
 	 */
 	public IContextInformation[] computeContextInformation(ITextViewer viewer, int offset) {
 		int contextInformationPosition= guessContextInformationPosition(viewer, offset);
 		List result= addContextInformations(viewer, contextInformationPosition);
 		return (IContextInformation[]) result.toArray(new IContextInformation[result.size()]);
 	}

 	/**
 	 * Order the given proposals.
 	 */
 	private ICompletionProposal[] order(ICompletionProposal[] proposals) {
 		Arrays.sort(proposals, fComparator);
 		return proposals;
 	}

 	/**
 	 * @see IContentAssistProcessor#computeCompletionProposals(ITextViewer, int)
 	 */
 	public ICompletionProposal[] computeCompletionProposals(ITextViewer viewer, int offset) {
 		int contextInformationPosition= guessContextInformationPosition(viewer, offset);
 		return internalComputeCompletionProposals(viewer, offset, contextInformationPosition);
 	}

 	private ICompletionProposal[] internalComputeCompletionProposals(ITextViewer viewer, int offset, int contextOffset) {

 		ICompilationUnit unit= fManager.getWorkingCopy(fEditor.getEditorInput());
 		IJavaCompletionProposal[] results;

 		ResultCollector collector;
 		if (PreferenceConstants.getPreferenceStore().getBoolean(PreferenceConstants.CODEASSIST_FILL_ARGUMENT_NAMES)) {
 			collector= fExperimentalCollector;
 		} else {
 			collector= fCollector;
 		}

 		try {
 			if (unit != null) {

 				collector.setPreventEating(false);
 				collector.reset(offset, contextOffset, unit.getJavaProject(), fAllowAddImports ? unit : null);
 				collector.setViewer(viewer);

 				Point selection= viewer.getSelectedRange();
 				if (selection.y > 0)
 				collector.setReplacementLength(selection.y);

 				unit.codeComplete(offset, collector);
 			}
 		} catch (JavaModelException x) {
 			Shell shell= viewer.getTextWidget().getShell();
 			if (x.isDoesNotExist() && unit != null && !unit.getJavaProject().isOnClasspath(unit))
 				MessageDialog.openInformation(shell, JavaTextMessages.getString("CompletionProcessor.error.notOnBuildPath.title"), JavaTextMessages.getString("CompletionProcessor.error.notOnBuildPath.message"));  //$NON-NLS-1$//$NON-NLS-2$
 			else
 				ErrorDialog.openError(shell, JavaTextMessages.getString("CompletionProcessor.error.accessing.title"), JavaTextMessages.getString("CompletionProcessor.error.accessing.message"), x.getStatus()); //$NON-NLS-2$ //$NON-NLS-1$
 		}

 		results= collector.getResults();

 		if (fTemplateEngine != null) {
 			try {
 				fTemplateEngine.reset();
 				fTemplateEngine.complete(viewer, offset, unit);
 			} catch (JavaModelException x) {
 				Shell shell= viewer.getTextWidget().getShell();
 				ErrorDialog.openError(shell, JavaTextMessages.getString("CompletionProcessor.error.accessing.title"), JavaTextMessages.getString("CompletionProcessor.error.accessing.message"), x.getStatus()); //$NON-NLS-2$ //$NON-NLS-1$
 			}

 			TemplateProposal[] templateResults= fTemplateEngine.getResults();

 			// update relavance of template proposals that match with a keyword
 			JavaCompletionProposal[] keyWordResults= collector.getKeywordCompletions();
 			for (int i= 0; i < keyWordResults.length; i++) {
 				String keyword= keyWordResults[i].getReplacementString();
 				for (int k= 0; k < templateResults.length; k++) {
 					TemplateProposal curr= templateResults[k];
 					if (keyword.equals(curr.getTemplate().getName())) {
 						curr.setRelevance(keyWordResults[i].getRelevance());
 					}
 				}
 			}

 			// concatenate arrays
 			IJavaCompletionProposal[] total= new IJavaCompletionProposal[results.length + templateResults.length];
 			System.arraycopy(templateResults, 0, total, 0, templateResults.length);
 			System.arraycopy(results, 0, total, templateResults.length, results.length);
 			results= total;
 		}

 		fNumberOfComputedResults= (results == null ? 0 : results.length);

 		/*
 		 * Order here and not in result collector to make sure that the order
 		 * applies to all proposals and not just those of the compilation unit.
 		 */
 		return order(results);
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2000, 2003 IBM Corporation and others.
	* All rights reserved. This program and the accompanying materials
	* are made available under the terms of the Common Public License v1.0
	* which accompanies this distribution, and is available at
	* http://www.eclipse.org/legal/cpl-v10.html
	*
	* Contributors:
	* IBM Corporation - initial API and implementation
	*******************************************************************************/
	package org.eclipse.jdt.internal.ui.text.java;



	import java.io.IOException;
	import java.util.ArrayList;
	import java.util.Arrays;
	import java.util.Hashtable;
	import java.util.List;

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

	import org.eclipse.jface.dialogs.ErrorDialog;
	import org.eclipse.jface.dialogs.MessageDialog;
	import org.eclipse.jface.text.IDocument;
	import org.eclipse.jface.text.ITextViewer;
	import org.eclipse.jface.text.contentassist.ICompletionProposal;
	import org.eclipse.jface.text.contentassist.IContentAssistProcessor;
	import org.eclipse.jface.text.contentassist.IContextInformation;
	import org.eclipse.jface.text.contentassist.IContextInformationExtension;
	import org.eclipse.jface.text.contentassist.IContextInformationValidator;

	import org.eclipse.ui.IEditorPart;

	import org.eclipse.jdt.core.ICompilationUnit;
	import org.eclipse.jdt.core.JavaCore;
	import org.eclipse.jdt.core.JavaModelException;

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

	import org.eclipse.jdt.internal.corext.template.ContextType;
	import org.eclipse.jdt.internal.corext.template.ContextTypeRegistry;

	import org.eclipse.jdt.internal.ui.JavaPlugin;
	import org.eclipse.jdt.internal.ui.JavaUIMessages;
	import org.eclipse.jdt.internal.ui.text.JavaCodeReader;
	import org.eclipse.jdt.internal.ui.text.template.TemplateEngine;
	import org.eclipse.jdt.internal.ui.text.template.TemplateProposal;


	/**
	* Java completion processor.
	*/
	public class JavaCompletionProcessor implements IContentAssistProcessor {

	private static class ContextInformationWrapper implements IContextInformation, IContextInformationExtension {

	private final IContextInformation fContextInformation;
	private int fPosition;

	public ContextInformationWrapper(IContextInformation contextInformation) {
	fContextInformation= contextInformation;
	}

	/*
	* @see IContextInformation#getContextDisplayString()
	*/
	public String getContextDisplayString() {
	return fContextInformation.getContextDisplayString();
	}

	/*
	* @see IContextInformation#getImage()
	*/
	public Image getImage() {
	return fContextInformation.getImage();
	}

	/*
	* @see IContextInformation#getInformationDisplayString()
	*/
	public String getInformationDisplayString() {
	return fContextInformation.getInformationDisplayString();
	}

	/*
	* @see IContextInformationExtension#getContextInformationPosition()
	*/
	public int getContextInformationPosition() {
	return fPosition;
	}

	public void setContextInformationPosition(int position) {
	fPosition= position;
	}

	/*
	* @see org.eclipse.jface.text.contentassist.IContextInformation#equals(java.lang.Object)
	*/
	public boolean equals(Object object) {
	if (object instanceof ContextInformationWrapper)
	return fContextInformation.equals(((ContextInformationWrapper) object).fContextInformation);
	else
	return fContextInformation.equals(object);
	}
	}


	private final static String VISIBILITY= JavaCore.CODEASSIST_VISIBILITY_CHECK;
	private final static String ENABLED= "enabled"; //$NON-NLS-1$
	private final static String DISABLED= "disabled"; //$NON-NLS-1$


	protected IWorkingCopyManager fManager;
	private IEditorPart fEditor;
	private ResultCollector fCollector;
	private IContextInformationValidator fValidator;

	private char[] fProposalAutoActivationSet;
	private JavaCompletionProposalComparator fComparator;
	private boolean fAllowAddImports;

	private TemplateEngine fTemplateEngine;
	private ExperimentalResultCollector fExperimentalCollector;

	private int fNumberOfComputedResults= 0;


	public JavaCompletionProcessor(IEditorPart editor) {
	fEditor= editor;
	fCollector= new ResultCollector();
	fManager= JavaPlugin.getDefault().getWorkingCopyManager();
	ContextType contextType= ContextTypeRegistry.getInstance().getContextType("java"); //$NON-NLS-1$
	if (contextType != null)
	fTemplateEngine= new TemplateEngine(contextType);
	fExperimentalCollector= new ExperimentalResultCollector();
	fAllowAddImports= true;

	fComparator= new JavaCompletionProposalComparator();
	}

	/**
	* Sets this processor's set of characters triggering the activation of the
	* completion proposal computation.
	*
	* @param activationSet the activation set
	*/
	public void setCompletionProposalAutoActivationCharacters(char[] activationSet) {
	fProposalAutoActivationSet= activationSet;
	}

	/**
	* Tells this processor to restrict its proposal to those element
	* visible in the actual invocation context.
	*
	* @param restrict <code>true</code> if proposals should be restricted
	*/
	public void restrictProposalsToVisibility(boolean restrict) {
	Hashtable options= JavaCore.getOptions();
	Object value= options.get(VISIBILITY);
	if (value instanceof String) {
	String newValue= restrict ? ENABLED : DISABLED;
	if ( !newValue.equals(value)) {
	options.put(VISIBILITY, newValue);
	JavaCore.setOptions(options);
	}
	}
	}

	/**
	* Tells this processor to order the proposals alphabetically.
	*
	* @param order <code>true</code> if proposals should be ordered.
	*/
	public void orderProposalsAlphabetically(boolean order) {
	fComparator.setOrderAlphabetically(order);
	}

	/**
	* Tells this processor to restrict is proposals to those
	* starting with matching cases.
	*
	* @param restrict <code>true</code> if proposals should be restricted
	*/
	public void restrictProposalsToMatchingCases(boolean restrict) {
	// not yet supported
	}

	/**
	* Tells this processor to add import statement for proposals that have
	* a fully qualified type name
	*
	* @param restrict <code>true</code> if import can be added
	*/
	public void allowAddingImports(boolean allowAddingImports) {
	fAllowAddImports= allowAddingImports;
	}

	/**
	* @see IContentAssistProcessor#getErrorMessage()
	*/
	public String getErrorMessage() {

	if (fNumberOfComputedResults == 0) {
	String errorMsg= fCollector.getErrorMessage();
	if (errorMsg == null \|\| errorMsg.trim().length() == 0)
	errorMsg= JavaUIMessages.getString("JavaEditor.codeassist.noCompletions"); //$NON-NLS-1$
	return errorMsg;
	}

	if (PreferenceConstants.getPreferenceStore().getBoolean(PreferenceConstants.CODEASSIST_FILL_ARGUMENT_NAMES))
	return fExperimentalCollector.getErrorMessage();

	return fCollector.getErrorMessage();
	}

	/**
	* @see IContentAssistProcessor#getContextInformationValidator()
	*/
	public IContextInformationValidator getContextInformationValidator() {
	if (fValidator == null)
	fValidator= new JavaParameterListValidator();
	return fValidator;
	}

	/**
	* @see IContentAssistProcessor#getContextInformationAutoActivationCharacters()
	*/
	public char[] getContextInformationAutoActivationCharacters() {
	return null;
	}

	/**
	* @see IContentAssistProcessor#getCompletionProposalAutoActivationCharacters()
	*/
	public char[] getCompletionProposalAutoActivationCharacters() {
	return fProposalAutoActivationSet;
	}

	private boolean looksLikeMethod(JavaCodeReader reader) throws IOException {
	int curr= reader.read();
	while (curr != JavaCodeReader.EOF && Character.isWhitespace((char) curr))
	curr= reader.read();

	if (curr == JavaCodeReader.EOF)
	return false;

	return Character.isJavaIdentifierPart((char) curr) \|\| Character.isJavaIdentifierStart((char) curr);
	}

	private int guessContextInformationPosition(ITextViewer viewer, int offset) {
	int contextPosition= offset;

	IDocument document= viewer.getDocument();

	try {

	JavaCodeReader reader= new JavaCodeReader();
	reader.configureBackwardReader(document, offset, true, true);

	int nestingLevel= 0;

	int curr= reader.read();
	while (curr != JavaCodeReader.EOF) {

	if (')' == (char) curr)
	++ nestingLevel;

	else if ('(' == (char) curr) {
	-- nestingLevel;

	if (nestingLevel < 0) {
	int start= reader.getOffset();
	if (looksLikeMethod(reader))
	return start + 1;
	}
	}

	curr= reader.read();
	}
	} catch (IOException e) {
	}

	return contextPosition;
	}

	private List addContextInformations(ITextViewer viewer, int offset) {
	ICompletionProposal[] proposals= internalComputeCompletionProposals(viewer, offset, -1);

	List result= new ArrayList();
	for (int i= 0; i < proposals.length; i++) {
	IContextInformation contextInformation= proposals[i].getContextInformation();
	if (contextInformation != null) {
	ContextInformationWrapper wrapper= new ContextInformationWrapper(contextInformation);
	wrapper.setContextInformationPosition(offset);
	result.add(wrapper);
	}
	}
	return result;
	}

	/**
	* @see IContentAssistProcessor#computeContextInformation(ITextViewer, int)
	*/
	public IContextInformation[] computeContextInformation(ITextViewer viewer, int offset) {
	int contextInformationPosition= guessContextInformationPosition(viewer, offset);
	List result= addContextInformations(viewer, contextInformationPosition);
	return (IContextInformation[]) result.toArray(new IContextInformation[result.size()]);
	}

	/**
	* Order the given proposals.
	*/
	private ICompletionProposal[] order(ICompletionProposal[] proposals) {
	Arrays.sort(proposals, fComparator);
	return proposals;
	}

	/**
	* @see IContentAssistProcessor#computeCompletionProposals(ITextViewer, int)
	*/
	public ICompletionProposal[] computeCompletionProposals(ITextViewer viewer, int offset) {
	int contextInformationPosition= guessContextInformationPosition(viewer, offset);
	return internalComputeCompletionProposals(viewer, offset, contextInformationPosition);
	}

	private ICompletionProposal[] internalComputeCompletionProposals(ITextViewer viewer, int offset, int contextOffset) {

	ICompilationUnit unit= fManager.getWorkingCopy(fEditor.getEditorInput());
	IJavaCompletionProposal[] results;

	ResultCollector collector;
	if (PreferenceConstants.getPreferenceStore().getBoolean(PreferenceConstants.CODEASSIST_FILL_ARGUMENT_NAMES)) {
	collector= fExperimentalCollector;
	} else {
	collector= fCollector;
	}

	try {
	if (unit != null) {

	collector.setPreventEating(false);
	collector.reset(offset, contextOffset, unit.getJavaProject(), fAllowAddImports ? unit : null);
	collector.setViewer(viewer);

	Point selection= viewer.getSelectedRange();
	if (selection.y > 0)
	collector.setReplacementLength(selection.y);

	unit.codeComplete(offset, collector);
	}
	} catch (JavaModelException x) {
	Shell shell= viewer.getTextWidget().getShell();
	if (x.isDoesNotExist() && unit != null && !unit.getJavaProject().isOnClasspath(unit))
	MessageDialog.openInformation(shell, JavaTextMessages.getString("CompletionProcessor.error.notOnBuildPath.title"), JavaTextMessages.getString("CompletionProcessor.error.notOnBuildPath.message")); //$NON-NLS-1$//$NON-NLS-2$
	else
	ErrorDialog.openError(shell, JavaTextMessages.getString("CompletionProcessor.error.accessing.title"), JavaTextMessages.getString("CompletionProcessor.error.accessing.message"), x.getStatus()); //$NON-NLS-2$ //$NON-NLS-1$
	}

	results= collector.getResults();

	if (fTemplateEngine != null) {
	try {
	fTemplateEngine.reset();
	fTemplateEngine.complete(viewer, offset, unit);
	} catch (JavaModelException x) {
	Shell shell= viewer.getTextWidget().getShell();
	ErrorDialog.openError(shell, JavaTextMessages.getString("CompletionProcessor.error.accessing.title"), JavaTextMessages.getString("CompletionProcessor.error.accessing.message"), x.getStatus()); //$NON-NLS-2$ //$NON-NLS-1$
	}

	TemplateProposal[] templateResults= fTemplateEngine.getResults();

	// update relavance of template proposals that match with a keyword
	JavaCompletionProposal[] keyWordResults= collector.getKeywordCompletions();
	for (int i= 0; i < keyWordResults.length; i++) {
	String keyword= keyWordResults[i].getReplacementString();
	for (int k= 0; k < templateResults.length; k++) {
	TemplateProposal curr= templateResults[k];
	if (keyword.equals(curr.getTemplate().getName())) {
	curr.setRelevance(keyWordResults[i].getRelevance());
	}
	}
	}

	// concatenate arrays
	IJavaCompletionProposal[] total= new IJavaCompletionProposal[results.length + templateResults.length];
	System.arraycopy(templateResults, 0, total, 0, templateResults.length);
	System.arraycopy(results, 0, total, templateResults.length, results.length);
	results= total;
	}

	fNumberOfComputedResults= (results == null ? 0 : results.length);

	/*
	* Order here and not in result collector to make sure that the order
	* applies to all proposals and not just those of the compilation unit.
	*/
	return order(results);
	}
	}