org.eclipse.mylyn.java.ui/src/org/eclipse/mylyn/java/ui/editor/MylarJavaCompletionProcessor.java

/*******************************************************************************
 * Copyright (c) 2004 - 2005 University Of British Columbia 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:
 *     University Of British Columbia - initial API and implementation
 *******************************************************************************/
/*
 * Created on Mar 14, 2005
  */
package org.eclipse.mylar.java.ui.editor;

import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.TreeMap;

import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.jdt.core.IMember;
import org.eclipse.jdt.internal.ui.text.java.JavaCompletionProcessor;
import org.eclipse.jdt.internal.ui.text.java.JavaCompletionProposal;
import org.eclipse.jdt.internal.ui.text.java.LazyJavaCompletionProposal;
import org.eclipse.jdt.internal.ui.text.java.MemberProposalInfo;
import org.eclipse.jdt.internal.ui.text.java.ProposalInfo;
import org.eclipse.jface.text.contentassist.ICompletionProposal;
import org.eclipse.jface.text.contentassist.TextContentAssistInvocationContext;
import org.eclipse.mylar.core.IMylarElement;
import org.eclipse.mylar.core.MylarPlugin;
import org.eclipse.mylar.core.internal.MylarContextManager;
import org.eclipse.mylar.dt.MylarWebRef;
import org.eclipse.ui.IEditorPart;

/**
 * @author Mik Kersten
 * 
 * HACK: uses reflection to get around accessibility restriction.
 */
public class MylarJavaCompletionProcessor extends JavaCompletionProcessor {

    public MylarJavaCompletionProcessor(IEditorPart editor, String partition) {
        super(editor, partition); 
    }

	@MylarWebRef(name="Reflection documentation", url="http://www.onjava.com/pub/a/onjava/2003/11/12/reflection.html?page=last")
    @Override
	protected List filterAndSortProposals(List proposals, IProgressMonitor monitor, TextContentAssistInvocationContext context) {
		super.filterAndSortProposals(proposals, monitor, context);
        try {
            Method method = MemberProposalInfo.class.getDeclaredMethod("resolveMember", new Class[] { } );
            method.setAccessible(true);
            TreeMap<Float, ICompletionProposal> interesting = new TreeMap<Float, ICompletionProposal>();
            List<ICompletionProposal> rest = new ArrayList<ICompletionProposal>();
            int unresolvedProposals = 0;
            for (Object proposalObject : proposals) {
            	ICompletionProposal proposal = (ICompletionProposal)proposalObject;
                ProposalInfo info = null;
                if (proposal instanceof JavaCompletionProposal) {
                    info = ((JavaCompletionProposal)proposal).getProposalInfo();
                } else if (proposal instanceof LazyJavaCompletionProposal) {
                    info = ((LazyJavaCompletionProposal)proposal).getProposalInfo();
                } 
                boolean added = false;
                try { // HACK
                    if (info != null) {
                        IMember member = null; 
                        if (info instanceof MemberProposalInfo) member = (IMember)method.invoke(info, new Object[] { });
                        if (member == null || MylarPlugin.getContextManager().getActiveContext() == null) {
                            // nothing for now
                        	rest.add(proposal);
                        } else {
                        	IMylarElement node = MylarPlugin.getContextManager().getElement(member.getHandleIdentifier()); 
                            if (node != null) {
                            	float interest = node.getDegreeOfInterest().getValue();
	                            if (interest > MylarContextManager.getScalingFactors().getInteresting()) {
	                                interesting.put(-interest, proposal);  // negative to invert sorting order
	                            } else {
	                            	rest.add(proposal);
	                            }
                            }
                        } 
                        added = true;
                    }
                } catch (Exception e) {
                	MylarPlugin.log(e, "proposals problem");
                } 
                if (!added) {
                	if (proposal instanceof JavaCompletionProposal) {
                		unresolvedProposals++;
                		interesting.put((float)unresolvedProposals - 100000, proposal); // HACK: should be parametrized
                	} else {
                		rest.add(proposal);
                	}
                }
            }
            if (interesting.keySet().size() == 0) {
                return proposals;
            } else {
                ICompletionProposal[] sorted = new ICompletionProposal[interesting.keySet().size() + rest.size() + 1];
                int i = 0;
                for (Float f : interesting.keySet()) {
                    sorted[i] = interesting.get(f);
                    i++; 
                }    
                if (interesting.keySet().size() > 0) {
                    int replacementOffset = -1;
                    if (sorted[i-1] instanceof JavaCompletionProposal) {
                        replacementOffset = ((JavaCompletionProposal)sorted[i-1]).getReplacementOffset();
                    } else if (sorted[i-1] instanceof LazyJavaCompletionProposal) {
                        replacementOffset = ((LazyJavaCompletionProposal)sorted[i-1]).getReplacementOffset();
                    } else {
                        MylarPlugin.log("Could not create proposal separator for class: " + sorted[i-1].getClass(), this);
                    }
                    sorted[i] = new JavaCompletionProposal("", replacementOffset, 0, null, "----------------", 0);
                    i++;
                } 
                for (ICompletionProposal proposal : rest) {
                    sorted[i] = proposal;
                    i++;
                }
                return Arrays.asList(sorted);
            }
        } catch (Exception e) {
        	MylarPlugin.log(e, "completion proposal failed");
        }
        return null;
    } 
}