1 /*
2 * ====================================================================
3 * Licensed to the Apache Software Foundation (ASF) under one
4 * or more contributor license agreements. See the NOTICE file
5 * distributed with this work for additional information
6 * regarding copyright ownership. The ASF licenses this file
7 * to you under the Apache License, Version 2.0 (the
8 * "License"); you may not use this file except in compliance
9 * with the License. You may obtain a copy of the License at
10 *
11 * http://www.apache.org/licenses/LICENSE-2.0
12 *
13 * Unless required by applicable law or agreed to in writing,
14 * software distributed under the License is distributed on an
15 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
16 * KIND, either express or implied. See the License for the
17 * specific language governing permissions and limitations
18 * under the License.
19 * ====================================================================
20 *
21 * This software consists of voluntary contributions made by many
22 * individuals on behalf of the Apache Software Foundation. For more
23 * information on the Apache Software Foundation, please see
24 * <http://www.apache.org/>.
25 *
26 */
27
28 package org.apache.hc.core5.http.examples;
29
30 import org.apache.hc.core5.util.VersionInfo;
31
32 /**
33 * Prints version information for debugging purposes.
34 * This can be used to verify that the correct versions of the
35 * HttpComponent JARs are picked up from the classpath.
36 *
37 *
38 */
39 public class PrintVersionInfo {
40
41 /** A default list of module packages. */
42 private final static String[] MODULE_LIST = {
43 "org.apache.http", // HttpCore
44 "org.apache.http.client", // HttpClient
45 };
46
47
48 /**
49 * Prints version information.
50 *
51 * @param args command line arguments. Leave empty to print version
52 * information for the default packages. Otherwise, pass
53 * a list of packages for which to get version info.
54 */
55 public static void main(final String args[]) {
56 final String[] pckgs = (args.length > 0) ? args : MODULE_LIST;
57 VersionInfo[] via = VersionInfo.loadVersionInfo(pckgs, null);
58 System.out.println("version info for thread context classloader:");
59 for (int i=0; i<via.length; i++)
60 System.out.println(via[i]);
61
62 System.out.println();
63
64 // if the version information for the classloader of this class
65 // is different from that for the thread context classloader,
66 // there may be a problem with multiple versions in the classpath
67
68 via = VersionInfo.loadVersionInfo
69 (pckgs, PrintVersionInfo.class.getClassLoader());
70 System.out.println("version info for static classloader:");
71 for (int i=0; i<via.length; i++)
72 System.out.println(via[i]);
73 }
74 }
75