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 
  24 package jdk.testlibrary;
  25 
  26 import static jdk.testlibrary.Asserts.assertTrue;
  27 
  28 import java.io.IOException;
  29 import java.net.InetAddress;
  30 import java.net.ServerSocket;
  31 import java.net.UnknownHostException;
  32 import java.util.ArrayList;
  33 import java.util.List;
  34 
  35 /**
  36  * Common library for various test helper functions.
  37  */
  38 public 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 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 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             System.out.println("Retrieving free port...");
 103             Thread.sleep(100);
 104 
 105             ServerSocket serverSocket = null;
 106             try {
 107                 serverSocket = new ServerSocket(0);
 108                 port = serverSocket.getLocalPort();
 109             } finally {
 110                 serverSocket.close();
 111             }
 112         }
 113 
 114         System.out.println("Free port: " + port);
 115         return port;
 116     }
 117     
 118     /**
 119      * Returns the name of the local host.
 120      * 
 121      * @return Host name
 122      * @throws UnknownHostException if IP address of a host could not be determined 
 123      */
 124     public static String getHostname() throws UnknownHostException {
 125         InetAddress inetAddress = InetAddress.getLocalHost();
 126         String hostName = inetAddress.getHostName();
 127         
 128         assertTrue((hostName != null && !hostName.isEmpty()), 
 129                 "Cannot get hostname");
 130 
 131         return hostName;
 132     }
 133 
 134 }