1 package org.codehaus.mojo.jaxb2.shared.environment.classloading;
2
3 /*
4 * Licensed to the Apache Software Foundation (ASF) under one
5 * or more contributor license agreements. See the NOTICE file
6 * distributed with this work for additional information
7 * regarding copyright ownership. The ASF licenses this file
8 * to you under the Apache License, Version 2.0 (the
9 * "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
22 /**
23 * <p>Specification for how to restore the original ThreadContext ClassLoader to a Thread.
24 * When we support JDK 1.7, this should really be an extension of AutoCloseable instead,
25 * to support the try-with-resources pattern. Typical use:</p>
26 * <pre>
27 * <code>
28 * // Create and set the ThreadContext ClassLoader
29 * ThreadContextClassLoaderHolder holder = null;
30 *
31 * try {
32 *
33 * holder = ThreadContextClassLoaderBuilder.createFor(getClass())
34 * .addPath("some/path")
35 * .addURL(someURL)
36 * .addPaths(aPathList)
37 * .buildAndSet();
38 *
39 * // ... perform operations using the newly set ThreadContext ClassLoader...
40 *
41 * } finally {
42 * // Restore the original ClassLoader
43 * holder.restoreClassLoaderAndReleaseThread();
44 * }
45 * </code>
46 * </pre>
47 *
48 * @author <a href="mailto:lj@jguru.se">Lennart Jörelid</a>, jGuru Europe AB
49 * @since 2.0
50 */
51 public interface ThreadContextClassLoaderHolder {
52
53 /**
54 * Restores the original ThreadContext ClassLoader, and nullifies
55 * any references to the Thread which had its ThreadContext
56 * ClassLoader altered.
57 */
58 void restoreClassLoaderAndReleaseThread();
59
60 /**
61 * Retrieves the ClassPath held by this ThreadContextClassLoaderHolder as a
62 * {@code File.pathSeparatorChar}-separated string. This is directly usable as a String argument by
63 * any external process.
64 *
65 * @return the ClassPath as an argument to external processes such as XJC.
66 */
67 String getClassPathAsArgument();
68 }