1   /*
2    * Copyright (c) 2011, 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   * @bug 6430675
27   * @summary Check for correct implementation of {Math, StrictMath}.round
28   */
29  public class RoundTests {
30      public static void main(String... args) {
31          int failures = 0;
32  
33          failures += testNearFloatHalfCases();
34          failures += testNearDoubleHalfCases();
35  
36          if (failures > 0) {
37              System.err.println("Testing {Math, StrictMath}.round incurred "
38                                 + failures + " failures.");
39              throw new RuntimeException();
40          }
41      }
42  
43      private static int testNearDoubleHalfCases() {
44          int failures = 0;
45          double [][] testCases = {
46              {+0x1.fffffffffffffp-2,  0.0},
47              {+0x1.0p-1,              1.0}, // +0.5
48              {+0x1.0000000000001p-1,  1.0},
49  
50              {-0x1.fffffffffffffp-2,  0.0},
51              {-0x1.0p-1,              0.0}, // -0.5
52              {-0x1.0000000000001p-1, -1.0},
53          };
54  
55          for(double[] testCase : testCases) {
56              failures += testNearHalfCases(testCase[0], (long)testCase[1]);
57          }
58  
59          return failures;
60      }
61  
62      private static int testNearHalfCases(double input, double expected) {
63          int failures = 0;
64  
65          failures += Tests.test("Math.round",        input, Math.round(input),       expected);
66          failures += Tests.test("StrictMath.round",  input, StrictMath.round(input), expected);
67  
68          return failures;
69      }
70  
71      private static int testNearFloatHalfCases() {
72          int failures = 0;
73          float [][] testCases = {
74              {+0x1.fffffep-2f,  0.0f},
75              {+0x1.0p-1f,       1.0f}, // +0.5
76              {+0x1.000002p-1f,  1.0f},
77  
78              {-0x1.fffffep-2f,  0.0f},
79              {-0x1.0p-1f,       0.0f}, // -0.5
80              {-0x1.000002p-1f, -1.0f},
81          };
82  
83          for(float[] testCase : testCases) {
84              failures += testNearHalfCases(testCase[0], (int)testCase[1]);
85          }
86  
87          return failures;
88      }
89  
90      private static int testNearHalfCases(float input, float expected) {
91          int failures = 0;
92  
93          failures += Tests.test("Math.round",        input, Math.round(input),       expected);
94          failures += Tests.test("StrictMath.round",  input, StrictMath.round(input), expected);
95  
96          return failures;
97      }
98  }