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 import java.io.BufferedInputStream;

    26 import java.io.ByteArrayOutputStream;

    27 import java.io.IOException;

    28 import java.util.concurrent.Callable;

    29 import java.util.Random;

    30 

    31 import com.oracle.java.testlibrary.Asserts;

    32 import com.oracle.java.testlibrary.ByteCodeLoader;

    33 import com.oracle.java.testlibrary.InfiniteLoop;

    34 import com.oracle.java.testlibrary.Utils;

    35 import sun.hotspot.WhiteBox;

    36 

    37 public final class Helper {

    38     public static final WhiteBox WHITE_BOX = WhiteBox.getWhiteBox();

    39     public static final Random RNG = Utils.getRandomInstance();

    40 

    41     private static final long THRESHOLD = WHITE_BOX.getIntxVMFlag("CompileThreshold");

    42     private static final String TEST_CASE_IMPL_CLASS_NAME = "Helper$TestCaseImpl";

    43     private static byte[] CLASS_DATA;

    44     static {

    45         try {

    46             CLASS_DATA = loadClassData(TEST_CASE_IMPL_CLASS_NAME);

    47         } catch (IOException e) {

    48             throw new Error("TESTBUG: cannot load class byte code", e);

    49         }

    50     }

    51 

    52     private Helper() {

    53     }

    54 

    55     public static void startInfiniteLoopThread(Runnable action) {

    56         startInfiniteLoopThread(action, 0L);

    57     }

    58 

    59     public static void startInfiniteLoopThread(Runnable action, long millis) {

    60         Thread t = new Thread(new InfiniteLoop(action, millis));

    61         t.setDaemon(true);

    62         t.start();

    63     }

    64 

    65     public static int callMethod(Callable<Integer> callable, int expected) {

    66         int result = 0;

    67         for (int i = 0; i < THRESHOLD; ++i) {

    68             try {

    69                 result = callable.call();

    70             } catch (Exception e) {

    71                 throw new AssertionError(

    72                         "Exception occurred during test method execution", e);

    73             }

    74             Asserts.assertEQ(result, expected, "Method returns unexpected value");

    75         }

    76         return result;

    77     }

    78 

    79     private static byte[] loadClassData(String name) throws IOException {

    80         try (BufferedInputStream in = new BufferedInputStream(

    81                 ClassLoader.getSystemResourceAsStream(name.replace(".", "/")

    82                         + ".class"))) {

    83             ByteArrayOutputStream result = new ByteArrayOutputStream();

    84             byte[] buffer = new byte[1024];

    85             int read;

    86             while ((read = in.read(buffer)) != -1) {

    87                 result.write(buffer, 0, read);

    88             }

    89             return result.toByteArray();

    90         }

    91     }

    92 

    93     public interface TestCase {

    94 

    95         public static TestCase get() {

    96             try {

    97                 Class clazz = ByteCodeLoader.load(

    98                         TEST_CASE_IMPL_CLASS_NAME, CLASS_DATA);

    99                 return (TestCase) clazz.newInstance();

   100             } catch (ReflectiveOperationException e) {

   101                 throw new Error(String.format(

   102                         "TESTBUG: error while creating %s instance from reloaded class",

   103                         TEST_CASE_IMPL_CLASS_NAME), e);

   104             }

   105         }

   106 

   107         Callable<Integer> getCallable();

   108         int method();

   109         int expectedValue();

   110     }

   111 

   112     public static class TestCaseImpl implements TestCase {

   113         private static final int RETURN_VALUE = 42;

   114         private static final int RECURSION_DEPTH = 10;

   115         private volatile int i;

   116 

   117         @Override

   118         public Callable<Integer> getCallable() {

   119             return () -> {

   120                 i = 0;

   121                 return method();

   122             };

   123         }

   124 

   125         @Override

   126         public int method() {

   127             ++i;

   128             int result = RETURN_VALUE;

   129             if (i < RECURSION_DEPTH) {

   130                 return result + method();

   131             }

   132             return result;

   133         }

   134 

   135         @Override

   136         public int expectedValue() {

   137             return RETURN_VALUE * RECURSION_DEPTH;

   138         }

   139     }

   140 

   141 }