7088913: Add compatible static hashCode(primitive) to primitive wrapper classes
Summary: Adds static utility methods to each primitive wrapper class to allow calculation of a hashCode value from an unboxed primitive.
Reviewed-by: darcy, smarks, dholmes
/*
* Copyright 2009 Google, Inc. 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 4245470 7088913
* @summary Test the primitive wrappers hashCode()
*/
import java.util.Objects;
import java.util.Random;
public class HashCode {
final Random rnd = new Random();
void testOrdinals(String args[]) throws Exception {
long[] longs = {
Long.MIN_VALUE,
Integer.MIN_VALUE,
Short.MIN_VALUE,
Character.MIN_VALUE,
Byte.MIN_VALUE,
-1, 0, 1,
Byte.MAX_VALUE,
Character.MAX_VALUE,
Short.MAX_VALUE,
Integer.MAX_VALUE,
Long.MAX_VALUE,
rnd.nextInt(),
};
for (long x : longs) {
check( new Long(x).hashCode() == (int)((long)x ^ (long)x>>>32));
check(Long.valueOf(x).hashCode() == (int)((long)x ^ (long)x>>>32));
check( (new Long(x)).hashCode() == Long.hashCode(x));
check( new Integer((int)x).hashCode() == (int) x);
check(Integer.valueOf((int)x).hashCode() == (int) x);
check( (new Integer((int)x)).hashCode() == Integer.hashCode((int)x));
check( new Short((short)x).hashCode() == (short) x);
check(Short.valueOf((short)x).hashCode() == (short) x);
check( (new Short((short)x)).hashCode() == Short.hashCode((short)x));
check( new Character((char) x).hashCode() == (char) x);
check(Character.valueOf((char) x).hashCode() == (char) x);
check( (new Character((char)x)).hashCode() == Character.hashCode((char)x));
check( new Byte((byte) x).hashCode() == (byte) x);
check(Byte.valueOf((byte) x).hashCode() == (byte) x);
check( (new Byte((byte)x)).hashCode() == Byte.hashCode((byte)x));
}
}
void testBoolean() {
check( Boolean.FALSE.hashCode() == 1237);
check( Boolean.TRUE.hashCode() == 1231);
check( Boolean.valueOf(false).hashCode() == 1237);
check( Boolean.valueOf(true).hashCode() == 1231);
check( (new Boolean(false)).hashCode() == 1237);
check( (new Boolean(true)).hashCode() == 1231);
check( Boolean.hashCode(false) == 1237);
check( Boolean.hashCode(true) == 1231);
}
void testFloat() {
float[] floats = {
Float.NaN,
Float.NEGATIVE_INFINITY,
-1f,
0f,
1f,
Float.POSITIVE_INFINITY
};
for(float f : floats) {
check( Float.hashCode(f) == Float.floatToIntBits(f));
check( Float.valueOf(f).hashCode() == Float.floatToIntBits(f));
check( (new Float(f)).hashCode() == Float.floatToIntBits(f));
}
}
void testDouble() {
double[] doubles = {
Double.NaN,
Double.NEGATIVE_INFINITY,
-1f,
0f,
1f,
Double.POSITIVE_INFINITY
};
for(double d : doubles) {
long bits = Double.doubleToLongBits(d);
int bitsHash = (int)(bits^(bits>>>32));
check( Double.hashCode(d) == bitsHash);
check( Double.valueOf(d).hashCode() == bitsHash);
check( (new Double(d)).hashCode() == bitsHash);
}
}
//--------------------- Infrastructure ---------------------------
volatile int passed = 0, failed = 0;
void pass() {passed++;}
void fail() {failed++; Thread.dumpStack();}
void fail(String msg) {System.err.println(msg); fail();}
void unexpected(Throwable t) {failed++; t.printStackTrace();}
void check(boolean cond) {if (cond) pass(); else fail();}
void equal(Object x, Object y) {
if (Objects.equals(x,y)) pass();
else fail(x + " not equal to " + y);}
public static void main(String[] args) throws Throwable {
new HashCode().instanceMain(args);}
public void instanceMain(String[] args) throws Throwable {
try { testOrdinals(args);
testBoolean();
testFloat();
testDouble();
} 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");}
}