proposal/mutant/src/main/org/apache/ant/core/execution/TaskDefinition.java

/*
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 2001 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution, if
 *    any, must include the following acknowlegement:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowlegement may appear in the software itself,
 *    if and wherever such third-party acknowlegements normally appear.
 *
 * 4. The names "The Jakarta Project", "Ant", and "Apache Software
 *    Foundation" must not be used to endorse or promote products derived
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 * 5. Products derived from this software may not be called "Apache"
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 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 */

package org.apache.ant.core.execution;

import java.util.*;
import java.net.URL;

/**
 * A Task definition provides the information necessary to execute
 * a task implementation.
 *
 * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
 */ 
public class TaskDefinition {
    /** The URL of the library which defines this task */
    private URL taskLibraryURL;
     
    /** The task's name */
    private String taskName;
    
    /** The task's class */
    private String taskClassName;
    
    /** The task's class loaded from the loader on demand. */
    private Class taskClass = null;
    
    /** The task's class loader. */
    private ClassLoader taskClassLoader;
    
    public TaskDefinition(URL taskLibraryURL, String taskName, String taskClassName, 
                          ClassLoader taskClassLoader) {
        this.taskLibraryURL = taskLibraryURL;
        this.taskName = taskName;
        this.taskClassName = taskClassName;
        this.taskClassLoader = taskClassLoader;
    }
    
    /**
     * Get the name of the task that is being defined.
     */
    public String getName() {
        return taskName;
    }
    
    /**
     * Get the classname of the task that is being defined.
     */
    public String getTaskClassName() {
        return taskClassName;
    }
    
    /**
     * Get the URL where this task was defined.
     *
     * @returns a URL of the lib defintion file
     */
    public URL getLibraryURL() {
        return taskLibraryURL;
    }
    
    /**
     * Get the task class for this task
     *
     * @return a class object for this task
     */
    public synchronized Class getExecutionTaskClass() throws ClassNotFoundException {
        if (taskClass == null) {
            taskClass = Class.forName(taskClassName, true, taskClassLoader);
        }
        return taskClass;
    }
}