/* This file is part of the db4o object database http://www.db4o.com

Copyright (C) 2004 - 2011  Versant Corporation http://www.versant.com

db4o is free software; you can redistribute it and/or modify it under
the terms of version 3 of the GNU General Public License as published
by the Free Software Foundation.

db4o is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
for more details.

You should have received a copy of the GNU General Public License along
with this program.  If not, see http://www.gnu.org/licenses/. */
package EDU.purdue.cs.bloat.tree;

import EDU.purdue.cs.bloat.cfg.*;
import EDU.purdue.cs.bloat.editor.*;

/**
 * CatchExpr represents an expression that catches an exception. A CatchExpr is
 * used when evaluating a method's try-catch blocks when a control flow graph is
 * constructed.
 * 
 * @see TryCatch
 * @see FlowGraph#FlowGraph(MethodEditor)
 * @see MethodEditor
 */
public class CatchExpr extends Expr {
	Type catchType;

	/**
	 * Constructor.
	 * 
	 * @param catchType
	 *            The type of the exception that is being caught.
	 * @param type
	 *            The type of this expression.
	 */
	public CatchExpr(final Type catchType, final Type type) {
		super(type);
		this.catchType = catchType;
	}

	public void visitForceChildren(final TreeVisitor visitor) {
	}

	public void visit(final TreeVisitor visitor) {
		visitor.visitCatchExpr(this);
	}

	public Type catchType() {
		return catchType;
	}

	public int exprHashCode() {
		return 8 + type.simple().hashCode() ^ catchType.hashCode();
	}

	public boolean equalsExpr(final Expr other) {
		if (other instanceof CatchExpr) {
			final CatchExpr c = (CatchExpr) other;

			if (catchType != null) {
				return catchType.equals(c.catchType);
			} else {
				return c.catchType == null;
			}
		}

		return false;
	}

	public Object clone() {
		return copyInto(new CatchExpr(catchType, type));
	}
}