Java example source code file (Test.java)

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Java - Java tags/keywords

arraylist, boolean, boxedarray, function, list, test, util

The Test.java Java example source code

/*
 * Copyright (c) 2009, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 *
 */

/**
 * @test
 * @bug 6851282
 * @summary JIT miscompilation results in null entry in array when using CompressedOops
 *
 * @run main/othervm/timeout=600 -Xmx256m -XX:+IgnoreUnrecognizedVMOptions -XX:+UseCompressedOops Test
 */

import java.util.ArrayList;
import java.util.List;

public class Test {
  void foo(A a, A[] as) {
    for (A a1 : as) {
      B[] filtered = a.c(a1);
      for (B b : filtered) {
        if (b == null) {
          System.out.println("bug: b == null");
          System.exit(97);
        }
      }
    }
  }

  public static void main(String[] args) {
    List<A> as = new ArrayList();
    for (int i = 0; i < 5000; i++) {
      List<B> bs = new ArrayList();
      for (int j = i; j < i + 1000; j++)
        bs.add(new B(j));
      as.add(new A(bs.toArray(new B[0])));
    }
    new Test().foo(as.get(0), as.subList(1, as.size()).toArray(new A[0]));
  }
}

class A {
  final B[] bs;

  public A(B[] bs) {
    this.bs = bs;
  }

  final B[] c(final A a) {
    return new BoxedArray<B>(bs).filter(new Function() {
      public Boolean apply(B arg) {
        for (B b : a.bs) {
          if (b.d == arg.d)
            return true;
        }
        return false;
      }
    });
  }
}

class BoxedArray<T> {

  private final T[] array;

  BoxedArray(T[] array) {
    this.array = array;
  }

  public T[] filter(Function<T, Boolean> function) {
    boolean[] include = new boolean[array.length];
    int len = 0;
    int i = 0;
    while (i < array.length) {
      if (function.apply(array[i])) {
        include[i] = true;
        len += 1;
      }
      i += 1;
    }
    T[] result = (T[]) java.lang.reflect.Array.newInstance(array.getClass().getComponentType(), len);
    len = 0;
    i = 0;
    while (len < result.length) {
      if (include[i]) {
        result[len] = array[i];
        len += 1;
      }
      i += 1;
    }
    return result;
  }
}

interface Function<T, R> {
  R apply(T arg);
}

class B {
  final int d;
  public B(int d) {
    this.d = d;
  }
}