org.apache.click.eclipse/src/org/apache/click/eclipse/ui/fieldassist/TypeNameContentProposalProvider.java

/*
 * 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.click.eclipse.ui.fieldassist;

import java.util.ArrayList;
import java.util.List;

import org.apache.click.eclipse.ClickUtils;
import org.eclipse.jdt.core.ICompilationUnit;
import org.eclipse.jdt.core.IJavaProject;
import org.eclipse.jdt.internal.core.DefaultWorkingCopyOwner;
import org.eclipse.jdt.internal.ui.text.java.JavaCompletionProposal;
import org.eclipse.jdt.internal.ui.text.java.LazyJavaTypeCompletionProposal;
import org.eclipse.jdt.ui.text.java.CompletionProposalCollector;
import org.eclipse.jdt.ui.text.java.IJavaCompletionProposal;
import org.eclipse.jface.fieldassist.IContentProposal;
import org.eclipse.jface.fieldassist.IContentProposalProvider;

/**
 * Provides type name completion in the Java project.
 * 
 * @author Naoki Takezoe
 */
public class TypeNameContentProposalProvider implements IContentProposalProvider {
	
	private IJavaProject project;
	private String packageName;
	
	/**
	 * Constructor.
	 * 
	 * @param project the Java project
	 */
	public TypeNameContentProposalProvider(IJavaProject project){
		this(project, null);
	}
	
	/**
	 * Constructor.
	 * 
	 * @param project the Java project
	 * @param packageName prefix of the package name
	 */
	public TypeNameContentProposalProvider(IJavaProject project, String packageName){
		this.project = project;
		this.packageName = packageName;
	}
	
	public IContentProposal[] getProposals(String contents, int position) {
		try {
			String rawContents = contents;
			
			CompletionProposalCollector collector = new CompletionProposalCollector(project);
			ICompilationUnit unit = FieldAssistUtils.getTemporaryCompilationUnit(project);
			
			contents = contents.substring(0, position);
			if(ClickUtils.isNotEmpty(packageName)){
				contents = packageName + "." + contents;
			}
			
			String source = "public class _xxx { public static void hoge(){ " + contents + "}}";
			
			FieldAssistUtils.setContentsToCU(unit, source);
			unit.codeComplete(source.length() - 2, collector, DefaultWorkingCopyOwner.PRIMARY);
			IJavaCompletionProposal[] proposals = collector.getJavaCompletionProposals();
			List<IContentProposal> result = new ArrayList<IContentProposal>();
			
			for(int j = 0; j < proposals.length; j++){
				if(proposals[j].getImage()!=null){
					String replaceString = null;
					if(proposals[j] instanceof LazyJavaTypeCompletionProposal){
						LazyJavaTypeCompletionProposal p = (LazyJavaTypeCompletionProposal)proposals[j];
						replaceString = p.getReplacementString();
					} else if(proposals[j] instanceof JavaCompletionProposal){
						JavaCompletionProposal p = (JavaCompletionProposal)proposals[j];
						replaceString = p.getReplacementString();
					}
					
					if(ClickUtils.isNotEmpty(replaceString)){
						if(replaceString.equals("_xxx")){
							continue;
						}
						if(ClickUtils.isNotEmpty(packageName) && replaceString.startsWith(packageName)){
							replaceString = replaceString.substring(packageName.length() + 1);
						}
						if(ClickUtils.isNotEmpty(replaceString) && replaceString.startsWith(rawContents)){
							result.add(new FieldAssistUtils.ContentProposalImpl(replaceString, position));
						}
					}
				}
			}
			
			return result.toArray(new IContentProposal[result.size()]);
			
		} catch(Exception ex){
			ex.printStackTrace();
		}
		
		return null;
	}

}