midletjadtextfilemidletchange.java

eclipseme的最新版本的source,欢迎j2me程序员使用

/**
 * Copyright (c) 2003-2005 Craig Setera
 * All Rights Reserved.
 * Licensed under the Eclipse Public License - v 1.0
 * For more information see http://www.eclipse.org/legal/epl-v10.html
 */
package eclipseme.core.internal.refactoring;

import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.eclipse.core.resources.IFile;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.ltk.core.refactoring.TextFileChange;
import org.eclipse.text.edits.DeleteEdit;
import org.eclipse.text.edits.ReplaceEdit;
import org.eclipse.text.edits.TextEdit;

/**
 * A TextFileChange for updating JAD files.
 * <p />
 * Copyright (c) 2003-2005 Craig Setera<br>
 * All Rights Reserved.<br>
 * Licensed under the Eclipse Public License - v 1.0<p/>
 * <br>
 * $Revision: 1.1 $
 * <br>
 * $Date: 2005/12/18 19:36:58 $
 * <br>
 * @author Craig Setera
 */
public class MidletJadTextFileMidletChange extends TextFileChange {
	private static final String REGEX = "MIDlet-\\d+:.*?,.*?,(";

	private Matcher matcher;
	private Pattern matchPattern;
	
	private int mode;
	private String oldName;
	private String newName;
	
	/**
	 * Create a new change instance.
	 * 
	 * @param mode
	 * @param name
	 * @param file
	 * @param matchPattern
	 * @param newName
	 */
	public MidletJadTextFileMidletChange(
		int mode,
		String name, 
		IFile file, 
		String oldName,
		String newName) 
	{
		super(name, file);
		this.mode = mode;
		this.oldName = oldName;
		this.newName = newName;
	}
	
	/**
	 * Return the matcher for handling the text file change.
	 * 
	 * @param pm
	 * @return
	 * @throws CoreException
	 */
	Matcher getMatcher(IProgressMonitor pm)
		throws CoreException
	{
		if (matcher == null) {
			pm.setTaskName("Initializing Regular Expression Matcher");
			String content = getCurrentContent(pm);
			matcher = getMatchPattern().matcher(content);
			pm.worked(1);
		}
		
		return matcher;
	}
	
	/**
	 * Initialize the text edit if it has not already been initialized.
	 * 
	 * @param pm
	 * @throws CoreException
	 */
	void initializeTextEdit(IProgressMonitor pm) 
		throws CoreException 
	{
		pm.setTaskName("Initializing Text Edit");
		
		TextEdit edit = null;
		Matcher matcher = getMatcher(pm);
		if (mode == MidletJadFileChangesCollector.MODE_RENAME) {
			int start = matcher.start(1);
			int end = matcher.end(1);
			edit = new ReplaceEdit(start, end - start, newName);
		} else {
			int start = matcher.start();
			int end = matcher.end();
			edit = new DeleteEdit(start, end - start);
		}
		
		setEdit(edit);
		pm.worked(1);
	}
	
	/**
	 * Get the match pattern for matching against a JAD file in search
	 * of the midlet name to be replaced.
	 * 
	 * @return
	 */
	private Pattern getMatchPattern() {
		if (matchPattern == null) {
			StringBuffer sb = new StringBuffer(REGEX).append(oldName).append(")");
			matchPattern = Pattern.compile(sb.toString());
		}
		
		return matchPattern;
	}
}