01: /*
02: * $Id: ClassUtils.java 471754 2006-11-06 14:55:09Z husted $
03: *
04: * Licensed to the Apache Software Foundation (ASF) under one
05: * or more contributor license agreements. See the NOTICE file
06: * distributed with this work for additional information
07: * regarding copyright ownership. The ASF licenses this file
08: * to you under the Apache License, Version 2.0 (the
09: * "License"); you may not use this file except in compliance
10: * with the License. You may obtain a copy of the License at
11: *
12: * http://www.apache.org/licenses/LICENSE-2.0
13: *
14: * Unless required by applicable law or agreed to in writing,
15: * software distributed under the License is distributed on an
16: * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17: * KIND, either express or implied. See the License for the
18: * specific language governing permissions and limitations
19: * under the License.
20: */
21: package org.apache.struts.chain.commands.util;
22:
23: /**
24: * <p>Utility methods to load application classes and create instances.</p>
25: *
26: * @version $Rev: 471754 $ $Date: 2005-11-12 13:01:44 -0500 (Sat, 12 Nov 2005)
27: * $
28: */
29: public final class ClassUtils {
30: // ---------------------------------------------------------- Static Methods
31:
32: /**
33: * <p>Return the <code>Class</code> object for the specified fully
34: * qualified class name, from this web application's class loader.
35: *
36: * @param className Fully qualified class name
37: * @throws ClassNotFoundException if the specified class cannot be loaded
38: */
39: public static Class getApplicationClass(String className)
40: throws ClassNotFoundException {
41: if (className == null) {
42: throw new NullPointerException(
43: "getApplicationClass called with null className");
44: }
45:
46: ClassLoader classLoader = Thread.currentThread()
47: .getContextClassLoader();
48:
49: if (classLoader == null) {
50: classLoader = ClassUtils.class.getClassLoader();
51: }
52:
53: return (classLoader.loadClass(className));
54: }
55:
56: /**
57: * <p>Return a new instance of the specified fully qualified class name,
58: * after loading the class (if necessary) from this web application's
59: * class loader.</p>
60: *
61: * @param className Fully qualified class name
62: * @throws ClassNotFoundException if the specified class cannot be loaded
63: * @throws IllegalAccessException if this class is not concrete
64: * @throws InstantiationException if this class has no zero-arguments
65: * constructor
66: */
67: public static Object getApplicationInstance(String className)
68: throws ClassNotFoundException, IllegalAccessException,
69: InstantiationException {
70: return (getApplicationClass(className).newInstance());
71: }
72: }
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