MessageUtil.java

package mit.edu.concurrencyrefactorings.util;

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

import org.eclipse.jdt.core.dom.ASTNode;
import org.eclipse.jdt.core.dom.CompilationUnit;
import org.eclipse.jdt.core.dom.Message;

public class MessageUtil {
	
	public static final int NODE_ONLY=				0;
	public static final int INCLUDE_FIRST_PARENT= 	1;
	public static final int INCLUDE_ALL_PARENTS= 	2;

	private static final Message[] EMPTY_MESSAGES= new Message[0];

	public static Message[] getMessages(ASTNode node, int flags) {
		ASTNode root= node.getRoot();
		if (!(root instanceof CompilationUnit))
			return EMPTY_MESSAGES;
		Message[] messages= ((CompilationUnit)root).getMessages();
		if (root == node)
			return messages;
		final int iterations= computeIterations(flags);
		List<Message> result= new ArrayList<Message>(5);
		for (int i= 0; i < messages.length; i++) {
			Message message= messages[i];
			ASTNode temp= node;
			int count= iterations;
			do {
				int nodeOffset= temp.getStartPosition();
				int messageOffset= message.getStartPosition();
				if (nodeOffset <= messageOffset && messageOffset < nodeOffset + temp.getLength()) {
					result.add(message);
					count= 0;
				} else {
					count--;
				}
			} while ((temp= temp.getParent()) != null && count > 0);
		}
		return result.toArray(new Message[result.size()]);
	}

	private static int computeIterations(int flags) {
		switch (flags) {
			case NODE_ONLY:
				return 1;
			case INCLUDE_ALL_PARENTS:
				return Integer.MAX_VALUE;
			case INCLUDE_FIRST_PARENT:
				return 2;
			default:
				return 1;
		}
	}
}