/*
 * Copyright (c) 2001-2004 Ant-Contrib project.  All rights reserved.
 *
 * Licensed 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 net.sf.antcontrib.logic;

import org.apache.tools.ant.BuildException;
import org.apache.tools.ant.taskdefs.Exit;
import org.apache.tools.ant.types.Reference;

/**
 * Extension of <code>&lt;fail&gt;</code> that can throw an exception
 * that is a reference in the project.
 *
 * <p>This may be useful inside the <code>&lt;catch&gt;</code> block
 * of a <code>&lt;trycatch&gt;</code> task if you want to rethrow the
 * exception just caught.</p>
 */
public class Throw extends Exit {

    private Reference ref;

    /**
     * The reference that points to a BuildException.
     */
    public void setRefid(Reference ref) {
        this.ref = ref;
    }

    public void execute() throws BuildException {
        Object reffed = ref != null 
            ? ref.getReferencedObject(getProject())
            : null;
        if (reffed != null && reffed instanceof BuildException) {
            throw (BuildException) reffed;
        }
        super.execute();
    }
}