Utils.java revision 8697:b04b124418d8 
1/*
2 * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23
24package jdk.testlibrary;
25
26import static jdk.testlibrary.Asserts.assertTrue;
27
28import java.io.IOException;
29import java.net.InetAddress;
30import java.net.ServerSocket;
31import java.net.UnknownHostException;
32import java.util.ArrayList;
33import java.util.List;
34
35/**
36 * Common library for various test helper functions.
37 */
38public final class Utils {
39
40    /**
41     * Returns the sequence used by operating system to separate lines.
42     */
43    public static final String NEW_LINE = System.getProperty("line.separator");
44
45    /**
46     * Returns the value of 'test.vm.opts'system property.
47     */
48    public static final String VM_OPTIONS = System.getProperty("test.vm.opts", "");
49
50
51    private Utils() {
52        // Private constructor to prevent class instantiation
53    }
54
55    /**
56     * Returns the list of VM options.
57     *
58     * @return List of VM options
59     */
60    public static List<String> getVmOptions() {
61        return getVmOptions(false);
62    }
63
64    /**
65     * Returns the list of VM options with -J prefix.
66     *
67     * @return The list of VM options with -J prefix
68     */
69    public static List<String> getForwardVmOptions() {
70        return getVmOptions(true);
71    }
72
73    private static List<String> getVmOptions(boolean forward) {
74        List<String> optionsList = new ArrayList<>();
75        String options = VM_OPTIONS.trim();
76        if (!options.isEmpty()) {
77            options = options.replaceAll("\\s+", " ");
78            for (String option : options.split(" ")) {
79                if (forward) {
80                    optionsList.add("-J" + option);
81                } else {
82                    optionsList.add(option);
83                }
84            }
85        }
86
87        return optionsList;
88    }
89
90    /**
91     * Returns the free port on the local host.
92     * The function will spin until a valid port number is found.
93     *
94     * @return The port number
95     * @throws InterruptedException if any thread has interrupted the current thread
96     * @throws IOException if an I/O error occurs when opening the socket
97     */
98    public static int getFreePort() throws InterruptedException, IOException {
99        int port = -1;
100
101        while (port <= 0) {
102            Thread.sleep(100);
103
104            ServerSocket serverSocket = null;
105            try {
106                serverSocket = new ServerSocket(0);
107                port = serverSocket.getLocalPort();
108            } finally {
109                serverSocket.close();
110            }
111        }
112
113        return port;
114    }
115
116    /**
117     * Returns the name of the local host.
118     *
119     * @return The host name
120     * @throws UnknownHostException if IP address of a host could not be determined
121     */
122    public static String getHostname() throws UnknownHostException {
123        InetAddress inetAddress = InetAddress.getLocalHost();
124        String hostName = inetAddress.getHostName();
125
126        assertTrue((hostName != null && !hostName.isEmpty()),
127                "Cannot get hostname");
128
129        return hostName;
130    }
131
132}
133