KickJava   Java API By Example, From Geeks To Geeks.

Java > Open Source Codes > org > apache > commons > logging > Wrapper


1 /*
2  * Copyright 2001-2004 The Apache Software Foundation.
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  * http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16
17 package org.apache.commons.logging;
18
19
20 import java.io.File JavaDoc;
21 import java.lang.reflect.Method JavaDoc;
22 import java.net.URL JavaDoc;
23 import java.net.URLClassLoader JavaDoc;
24 import java.util.ArrayList JavaDoc;
25 import java.util.List JavaDoc;
26
27
28 /**
29  * <p>Wrapper around test cases that need to have a custom class loader
30  * hierarchy assembled. The wrapper is configured by the following
31  * system properties:</p>
32  * <ul>
33  * <li><strong>wrapper.hierarchy</strong> - Descriptive code describing how
34  * the class loader hierarchy should be assembled:
35  * <ul>
36  * <li><strong>API</strong> - Parent class loader contains
37  * <code>commons-logging-api.jar</code> and child class loader
38  * contains <code>commons-logging.jar</code>. This is like the
39  * default configuration for Tomcat 4.1.</li>
40  * <li><strong>FULL</strong> - Parent class loader contains
41  * <code>commons-logging.jar</code>. This is what would happen
42  * if you replaced <code>commons-logging-api.jar</code> with
43  * <code>commons-logging.jar</code> so that you did not need to
44  * include the latter with your application.</li>
45  * </ul>
46  * The child class loader also unconditionally includes
47  * <code>commons-logging-tests.jar</code>.</li>
48  * <li><strong>wrapper.junit</strong> - Fully qualified pathname of the
49  * JUnit JAR file.</li>
50  * <li><strong>wrapper.log4j</strong> - Fully qualified pathname of the
51  * Log4J JAR file, which will be placed in whichever class loader
52  * <code>commons-logging.jar</code> is placed in, if specified.</li>
53  * <li><strong>wrapper.target</strong> - Fully qualified pathname of the
54  * "target" directory created by the build process. This directory
55  * must contain the <code>commons-logging.jar</code>,
56  * <code>commons-logging-api.jar</code>, and
57  * <code>commons-logging-tests.jar</code> files resulting from the
58  * execution of the <code>compile.tests</code> target.</li>
59  * <li><strong>wrapper.testcase</strong> - Fully qualified Java class name
60  * of a TestCase that will ultimately be executed. This class must
61  * exist in the <code>commons-logging-tests.jar</code> file.</li>
62  * </ul>
63  *
64  * <p>When executed, the system classpath for the wrapper should include
65  * only the wrapper class itself.</p>
66  *
67  * @author Craig R. McClanahan
68  * @version $Revision: 1.5 $ $Date: 2004/02/28 21:46:45 $
69  */
70
71 public class Wrapper {
72
73
74     public static void main(String JavaDoc args[]) {
75
76         try {
77
78             // Create variables we will need
79 List JavaDoc parentList = new ArrayList JavaDoc();
80             List JavaDoc childList = new ArrayList JavaDoc();
81             URL JavaDoc urls[] = null;
82
83             // Construct URLs for the various JAR files
84 File JavaDoc target = new File JavaDoc(System.getProperty("wrapper.target"));
85             URL JavaDoc commonsLogging =
86                 (new File JavaDoc(target, "commons-logging.jar")).toURL();
87             URL JavaDoc commonsLoggingApi =
88                 (new File JavaDoc(target, "commons-logging-api.jar")).toURL();
89             URL JavaDoc commonsLoggingTests =
90                 (new File JavaDoc(target, "commons-logging-tests.jar")).toURL();
91             URL JavaDoc junit =
92                 (new File JavaDoc(System.getProperty("wrapper.junit"))).toURL();
93             URL JavaDoc appender = null;
94             URL JavaDoc log4j = null;
95             if (System.getProperty("wrapper.log4j") != null) {
96                 log4j =
97                     (new File JavaDoc(System.getProperty("wrapper.log4j"))).toURL();
98                 appender =
99                     (new File JavaDoc(target, "commons-logging-appender.jar")).toURL();
100             }
101
102             // Construct class loader repository lists for supported scenarios
103 if ("API".equals(System.getProperty("wrapper.hierarchy"))) {
104                 parentList.add(commonsLoggingApi);
105                 childList.add(commonsLogging);
106                 if (log4j != null) {
107                     childList.add(log4j);
108                     childList.add(appender);
109                 }
110             } else { // Assumes "FULL"
111 parentList.add(commonsLogging);
112                 if (log4j != null) {
113                     parentList.add(log4j);
114                     childList.add(appender);
115                 }
116             }
117             childList.add(commonsLoggingTests);
118             childList.add(junit);
119
120             // Construt the parent and child class loaders
121 urls = (URL JavaDoc[]) parentList.toArray(new URL JavaDoc[parentList.size()]);
122             ClassLoader JavaDoc parent =
123                 new URLClassLoader JavaDoc(urls,
124                                    ClassLoader.getSystemClassLoader());
125             urls = (URL JavaDoc[]) childList.toArray(new URL JavaDoc[childList.size()]);
126             ClassLoader JavaDoc child = new URLClassLoader JavaDoc(urls, parent);
127
128             // Execute the test runner for this TestCase
129 ClassLoader JavaDoc old = Thread.currentThread().getContextClassLoader();
130             Thread.currentThread().setContextClassLoader(child);
131             Class JavaDoc clazz = child.loadClass("junit.textui.TestRunner");
132             String JavaDoc params[] = new String JavaDoc[1];
133             params[0] = System.getProperty("wrapper.testcase");
134             Method JavaDoc method = clazz.getMethod("main",
135                                             new Class JavaDoc[] { params.getClass() });
136             method.invoke(null, new Object JavaDoc[] { params });
137             Thread.currentThread().setContextClassLoader(old);
138
139         } catch (Exception JavaDoc e) {
140
141             System.out.println("Wrapper Exception Occurred: " + e);
142             e.printStackTrace(System.out);
143             System.exit(1);
144
145         }
146
147     }
148
149
150
151 }
152
Popular Tags