1 /*
2 * Copyright (c) 2014, 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 /*
25 * @test
26 * @summary Verify correctnes of the random generator from Utility.java
27 * @library /testlibrary
28 * @build com.oracle.java.testlibrary.*
29 * @run driver RandomGeneratorTest SAME_SEED
30 * @run driver RandomGeneratorTest NO_SEED
31 * @run driver RandomGeneratorTest DIFFERENT_SEED
32 */
33
34 import com.oracle.java.testlibrary.ProcessTools;
35 import com.oracle.java.testlibrary.Utils;
36 import java.util.ArrayList;
37 import java.util.List;
38 import java.util.Random;
39
40 /**
41 * The test verifies correctness of work {@link com.oracle.java.testlibrary.Utils#getRandomInstance()}.
42 * Test works in three modes: same seed provided, no seed provided and
43 * different seed provided. In the first case the test expects that all random numbers
44 * will be repeated in all next iterations. For other two modes test expects that
45 * randomly generated numbers differ from original.
46 */
47 public class RandomGeneratorTest {
48 private static final String SEED_VM_OPTION = "-D" + Utils.SEED_PROPERTY_NAME + "=";
49
50 public static void main( String[] args) throws Throwable {
51 if (args.length == 0) {
52 throw new Error("TESTBUG: No test mode provided.");
53 }
54 SeedOption seedOpt = SeedOption.valueOf(args[0]);
55 List<String> jvmArgs = new ArrayList<String>();
56 String optStr = seedOpt.getSeedOption();
57 if (optStr != null) {
58 jvmArgs.add(optStr);
59 }
60 jvmArgs.add(RandomRunner.class.getName());
61 String[] cmdLineArgs = jvmArgs.toArray(new String[jvmArgs.size()]);
62 String etalon = ProcessTools.executeTestJvm(cmdLineArgs).getOutput().trim();
63 seedOpt.verify(etalon, cmdLineArgs);
64 }
65
66 /**
67 * The utility enum helps to generate an appropriate string that should be passed
68 * to the command line depends on the testing mode. It is also responsible for the result
69 * validation.
70 */
71 private enum SeedOption {
72 SAME_SEED {
73 @Override
74 public String getSeedOption() {
75 return SEED_VM_OPTION + Utils.SEED;
76 }
77
78 @Override
79 protected boolean isOutputExpected(String orig, String output) {
80 return output.equals(orig);
81 }
82 },
83 DIFFERENT_SEED {
84 @Override
85 public String getSeedOption() {
86 return SEED_VM_OPTION + Utils.getRandomInstance().nextLong();
87 }
88
89 @Override
90 public void verify(String orig, String[] cmdLine) {
91 cmdLine[0] = getSeedOption();
92 super.verify(orig, cmdLine);
93 }
94 },
95 NO_SEED {
96 @Override
97 public String getSeedOption() {
98 return null;
99 }
100 };
101
102 /**
103 * Generates a string to be added as a command line argument.
104 * It contains "-D" prefix, system property name, '=' sign
105 * and seed value.
106 * @return command line argument
107 */
108 public abstract String getSeedOption();
109
110 protected boolean isOutputExpected(String orig, String output) {
111 return !output.equals(orig);
112 }
113
114 /**
115 * Verifies that the original output meets expectations
116 * depending on the test mode. It compares the output of second execution
117 * to original one.
118 * @param orig original output
119 * @param cmdLine command line arguments
120 * @throws Throwable - Throws an exception in case test failure.
121 */
122 public void verify(String orig, String[] cmdLine) {
123 String lastLineOrig = getLastLine(orig);
124 String lastLine;
125 try {
126 lastLine = getLastLine(ProcessTools.executeTestJvm(cmdLine).getOutput().trim());
127 } catch (Throwable t) {
128 throw new Error("TESTBUG: Unexpedted exception during jvm execution.", t);
129 }
130 if (!isOutputExpected(lastLineOrig, lastLine)) {
131 throw new AssertionError("Unexpected random number sequence for mode: " + this.name());
132 }
133 }
134
135 private static String getLastLine(String output) {
136 return output.substring(output.lastIndexOf(Utils.NEW_LINE)).trim();
137 }
138 }
139
140 /**
141 * The helper class generates several random numbers
142 * and prints them out.
143 */
144 public static class RandomRunner {
145 private static final int COUNT = 10;
146 public static void main(String[] args) {
147 StringBuilder sb = new StringBuilder();
148 Random rng = Utils.getRandomInstance();
149 for (int i = 0; i < COUNT; i++) {
150 sb.append(rng.nextLong()).append(' ');
151 }
152 System.out.println(sb.toString());
153 }
154 }
155 }