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/*
* Copyright (c) 2003, 2007, 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 4809442 6366832 4974878 6372554 4890211 6483125
* @summary Basic test for Collections.reverseOrder
* @author Josh Bloch, Martin Buchholz
*/
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.LinkedList;
import java.util.List;
public class ReverseOrder2 {
static final int N = 100;
static void realMain(String[] args) throws Throwable {
check(Collections.reverseOrder()
== Collections.reverseOrder(null));
check(Collections.reverseOrder()
== reincarnate(Collections.reverseOrder()));
check(Collections.reverseOrder(Collections.reverseOrder(cmp))
== cmp);
equal(Collections.reverseOrder(cmp),
Collections.reverseOrder(cmp));
equal(Collections.reverseOrder(cmp).hashCode(),
Collections.reverseOrder(cmp).hashCode());
check(Collections.reverseOrder(cmp).hashCode() !=
cmp.hashCode());
test(new ArrayList<String>());
test(new LinkedList<String>());
test2(new ArrayList<Integer>());
test2(new LinkedList<Integer>());
}
static void test(List<String> list) {
for (int i = 0; i < N; i++)
list.add(String.valueOf(i));
Collections.shuffle(list);
Collections.sort(list, Collections.reverseOrder(cmp));
equal(list, golden);
}
private static Comparator<String> cmp = new Comparator<>() {
public int compare(String s1, String s2) {
int i1 = Integer.parseInt(s1);
int i2 = Integer.parseInt(s2);
return (i1 < i2 ? Integer.MIN_VALUE : (i1 == i2 ? 0 : 1));
}
};
private static final List<String> golden = new ArrayList<>(N);
static {
for (int i = N-1; i >= 0; i--)
golden.add(String.valueOf(i));
}
static void test2(List<Integer> list) {
for (int i = 0; i < N; i++)
list.add(i);
Collections.shuffle(list);
Collections.sort(list, Collections.reverseOrder(null));
equal(list, golden2);
}
private static final List<Integer> golden2 = new ArrayList<>(N);
static {
for (int i = N-1; i >= 0; i--)
golden2.add(i);
}
//--------------------- Infrastructure ---------------------------
static volatile int passed = 0, failed = 0;
static void pass() {passed++;}
static void fail() {failed++; Thread.dumpStack();}
static void fail(String msg) {System.out.println(msg); fail();}
static void unexpected(Throwable t) {failed++; t.printStackTrace();}
static void check(boolean cond) {if (cond) pass(); else fail();}
static void equal(Object x, Object y) {
if (x == null ? y == null : x.equals(y)) pass();
else fail(x + " not equal to " + y);}
public static void main(String[] args) throws Throwable {
try {realMain(args);} catch (Throwable t) {unexpected(t);}
System.out.printf("%nPassed = %d, failed = %d%n%n", passed, failed);
if (failed > 0) throw new AssertionError("Some tests failed");}
static byte[] serializedForm(Object obj) {
try {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
new ObjectOutputStream(baos).writeObject(obj);
return baos.toByteArray();
} catch (IOException e) {throw new RuntimeException(e);}}
static Object readObject(byte[] bytes)
throws IOException, ClassNotFoundException {
InputStream is = new ByteArrayInputStream(bytes);
return new ObjectInputStream(is).readObject();}
@SuppressWarnings("unchecked")
static <T> T reincarnate(T obj) {
try {return (T) readObject(serializedForm(obj));}
catch (Exception e) {throw new RuntimeException(e);}}
}
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