| /* |
| * Copyright (c) 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 6410729 6586631 |
| * @summary Test previousClearBit, previousSetBit |
| * @key randomness |
| */ |
| |
| import java.util.*; |
| |
| public class PreviousBits { |
| |
| void testHashCode(final BitSet s) { |
| long h = 1234; |
| long[] words = s.toLongArray(); |
| for (int i = words.length; --i >= 0; ) |
| h ^= words[i] * (i + 1); |
| equal((int)((h >> 32) ^ h), s.hashCode()); |
| } |
| |
| void testOutOfBounds(final BitSet s) { |
| THROWS(IndexOutOfBoundsException.class, |
| new F(){void f(){ s.previousSetBit(-2);}}, |
| new F(){void f(){ s.previousClearBit(-2);}}, |
| new F(){void f(){ s.previousSetBit(Integer.MIN_VALUE);}}, |
| new F(){void f(){ s.previousClearBit(Integer.MIN_VALUE);}}, |
| new F(){void f(){ s.nextSetBit(-1);}}, |
| new F(){void f(){ s.nextClearBit(-1);}}, |
| new F(){void f(){ s.nextSetBit(Integer.MIN_VALUE);}}, |
| new F(){void f(){ s.nextClearBit(Integer.MIN_VALUE);}}); |
| } |
| |
| void test(String[] args) throws Throwable { |
| final BitSet s = new BitSet(); |
| |
| // Test empty bitset |
| testOutOfBounds(s); |
| testHashCode(s); |
| |
| for (int i = -1; i < 93;) { |
| equal(-1, s.previousSetBit(i)); |
| equal( i, s.previousClearBit(i)); |
| i++; |
| equal(-1, s.nextSetBit(i)); |
| equal( i, s.nextClearBit(i)); |
| } |
| |
| // Test "singleton" bitsets |
| for (int j = 0; j < 161; j++) { |
| s.clear(); |
| s.set(j); |
| testOutOfBounds(s); |
| testHashCode(s); |
| |
| for (int i = -1; i < j; i++) { |
| equal(-1, s.previousSetBit(i)); |
| equal( i, s.previousClearBit(i)); |
| if (i >= 0) { |
| equal(j, s.nextSetBit(i)); |
| equal(i, s.nextClearBit(i)); |
| } |
| } |
| |
| equal(j, s.previousSetBit(j)); |
| equal(j-1, s.previousClearBit(j)); |
| equal(j, s.nextSetBit(j)); |
| equal(j+1, s.nextClearBit(j)); |
| |
| for (int i = j+1; i < j+100; i++) { |
| equal(j, s.previousSetBit(i)); |
| equal(i, s.previousClearBit(i)); |
| equal(-1, s.nextSetBit(i)); |
| equal(i, s.nextClearBit(i)); |
| } |
| } |
| |
| // set even bits |
| s.clear(); |
| for (int i = 0; i <= 128; i+=2) |
| s.set(i); |
| testHashCode(s); |
| for (int i = 1; i <= 128; i++) { |
| equal(s.previousSetBit(i), |
| ((i & 1) == 0) ? i : i - 1); |
| equal(s.previousClearBit(i), |
| ((i & 1) == 0) ? i - 1 : i); |
| } |
| |
| // set odd bits as well |
| for (int i = 1; i <= 128; i+=2) |
| s.set(i); |
| testHashCode(s); |
| for (int i = 1; i <= 128; i++) { |
| equal(s.previousSetBit(i), i); |
| equal(s.previousClearBit(i), -1); |
| } |
| |
| // Test loops documented in javadoc |
| Random rnd = new Random(); |
| s.clear(); |
| for (int i = 0; i < 10; i++) |
| s.set(rnd.nextInt(1066)); |
| List<Integer> down = new ArrayList<Integer>(); |
| for (int i = s.length(); (i = s.previousSetBit(i-1)) >= 0; ) |
| down.add(i); |
| List<Integer> up = new ArrayList<Integer>(); |
| for (int i = s.nextSetBit(0); i >= 0; i = s.nextSetBit(i+1)) |
| up.add(i); |
| Collections.reverse(up); |
| equal(up, down); |
| } |
| |
| //--------------------- 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 (x == null ? y == null : x.equals(y)) pass(); |
| else fail(x + " not equal to " + y);} |
| public static void main(String[] args) throws Throwable { |
| new PreviousBits().instanceMain(args);} |
| void instanceMain(String[] args) throws Throwable { |
| try {test(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");} |
| abstract class F {abstract void f() throws Throwable;} |
| void THROWS(Class<? extends Throwable> k, F... fs) { |
| for (F f : fs) |
| try {f.f(); fail("Expected " + k.getName() + " not thrown");} |
| catch (Throwable t) { |
| if (k.isAssignableFrom(t.getClass())) pass(); |
| else unexpected(t);}} |
| } |