| /* |
| * Copyright (C) 2010 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package libcore.java.util; |
| |
| import java.util.Arrays; |
| import java.util.Random; |
| |
| public class RandomTest extends junit.framework.TestCase { |
| public void test_subclassing() throws Exception { |
| // http://b/2502231 |
| // Ensure that Random's constructors call setSeed by emulating the active ingredient |
| // from the bug: the subclass' setSeed had a side-effect necessary for the correct |
| // functioning of next. |
| class MyRandom extends Random { |
| public String state; |
| public MyRandom() { super(); } |
| public MyRandom(long l) { super(l); } |
| @Override protected synchronized int next(int bits) { return state.length(); } |
| @Override public synchronized void setSeed(long seed) { state = Long.toString(seed); } |
| } |
| // Test the 0-argument constructor... |
| MyRandom r1 = new MyRandom(); |
| r1.nextInt(); |
| assertNotNull(r1.state); |
| // Test the 1-argument constructor... |
| MyRandom r2 = new MyRandom(123L); |
| r2.nextInt(); |
| assertNotNull(r2.state); |
| } |
| |
| public void test_ints$() { |
| final int limit = 128; // We can't test for every element in an infinite stream. |
| |
| Random rand = new Random(0); |
| int[] rands = new int[limit]; |
| for(int i = 0; i < limit; ++i) { |
| rands[i] = rand.nextInt(); |
| } |
| |
| int[] streamRands = new Random(0).ints().limit(limit).toArray(); |
| assertTrue(Arrays.equals(rands, streamRands)); |
| } |
| |
| public void test_ints$L() { |
| final int size = 32; |
| |
| Random rand = new Random(0); |
| int[] rands = new int[size]; |
| for(int i = 0; i < size; ++i) { |
| rands[i] = rand.nextInt(); |
| } |
| |
| int[] streamRands = new Random(0).ints(size).toArray(); |
| assertTrue(Arrays.equals(rands, streamRands)); |
| assertEquals(size, new Random(0).ints(size).count()); |
| |
| try { |
| new Random(0).ints(-1); |
| fail(); |
| } catch (IllegalArgumentException expected) {} |
| } |
| |
| public void test_ints$II() { |
| final int limit = 128; // We can't test for every element in an infinite stream. |
| final int origin = 128, bound = 256; |
| |
| Random rand = new Random(0); |
| int[] rands = new int[limit]; |
| for(int i = 0; i < limit; ++i) { |
| rands[i] = rand.nextInt(bound - origin) + origin; |
| } |
| |
| int[] streamRands = new Random(0).ints(origin, bound).limit(limit).toArray(); |
| assertTrue(Arrays.equals(rands, streamRands)); |
| |
| try { |
| new Random(0).ints(100, 0); |
| fail(); |
| } catch (IllegalArgumentException expected) {} |
| } |
| |
| public void test_ints$LII() { |
| final int size = 32; |
| final int origin = 128, bound = 256; |
| |
| Random rand = new Random(0); |
| int[] rands = new int[size]; |
| for(int i = 0; i < size; ++i) { |
| rands[i] = rand.nextInt(bound - origin) + origin; |
| } |
| |
| int[] streamRands = new Random(0).ints(size, origin, bound).toArray(); |
| assertTrue(Arrays.equals(rands, streamRands)); |
| assertEquals(size, new Random(0).ints(size, origin, bound).count()); |
| |
| try { |
| new Random(0).ints(-1, 10, 20); |
| fail(); |
| } catch (IllegalArgumentException expected) {} |
| try { |
| new Random(0).ints(10, 100, 0); |
| fail(); |
| } catch (IllegalArgumentException expected) {} |
| } |
| |
| public void test_longs$() { |
| final int limit = 128; // We can't test for every element in an infinite stream. |
| |
| Random rand = new Random(0); |
| long[] rands = new long[limit]; |
| for(int i = 0; i < limit; ++i) { |
| rands[i] = rand.nextLong(); |
| } |
| |
| long[] streamRands = new Random(0).longs().limit(limit).toArray(); |
| assertTrue(Arrays.equals(rands, streamRands)); |
| } |
| |
| public void test_longs$L() { |
| final int size = 32; |
| |
| Random rand = new Random(0); |
| long[] rands = new long[size]; |
| for(int i = 0; i < size; ++i) { |
| rands[i] = rand.nextLong(); |
| } |
| |
| long[] streamRands = new Random(0).longs(size).toArray(); |
| assertTrue(Arrays.equals(rands, streamRands)); |
| assertEquals(size, new Random(0).longs(size).count()); |
| |
| try { |
| new Random(0).longs(-1); |
| fail(); |
| } catch (IllegalArgumentException expected) {} |
| } |
| |
| public void test_longs$II() { |
| final int limit = 128; // We can't test for every element in an infinite stream. |
| final int origin = 128, bound = 256; |
| |
| Random rand = new Random(0); |
| long[] rands = new long[limit]; |
| for(int i = 0; i < limit; ++i) { |
| rands[i] = (rand.nextLong() & 127) + origin; |
| } |
| |
| long[] streamRands = new Random(0).longs(origin, bound).limit(limit).toArray(); |
| assertTrue(Arrays.equals(rands, streamRands)); |
| |
| try { |
| new Random(0).longs(100, 0); |
| fail(); |
| } catch (IllegalArgumentException expected) {} |
| } |
| |
| public void test_longs$LII() { |
| final int size = 32; |
| final int origin = 128, bound = 256; |
| |
| Random rand = new Random(0); |
| long[] rands = new long[size]; |
| for(int i = 0; i < size; ++i) { |
| rands[i] = (rand.nextLong() & 127) + origin; |
| } |
| |
| long[] streamRands = new Random(0).longs(size, origin, bound).toArray(); |
| assertTrue(Arrays.equals(rands, streamRands)); |
| assertEquals(size, new Random(0).longs(size, origin, bound).count()); |
| |
| try { |
| new Random(0).longs(-1, 10, 20); |
| fail(); |
| } catch (IllegalArgumentException expected) {} |
| try { |
| new Random(0).longs(10, 100, 0); |
| fail(); |
| } catch (IllegalArgumentException expected) {} |
| } |
| |
| public void test_doubles$() { |
| final int limit = 128; // We can't test for every element in an infinite stream. |
| |
| Random rand = new Random(0); |
| double[] rands = new double[limit]; |
| for(int i = 0; i < limit; ++i) { |
| rands[i] = rand.nextDouble(); |
| } |
| |
| double[] streamRands = new Random(0).doubles().limit(limit).toArray(); |
| assertTrue(Arrays.equals(rands, streamRands)); |
| } |
| |
| public void test_doubles$L() { |
| final int size = 32; |
| |
| Random rand = new Random(0); |
| double[] rands = new double[size]; |
| for(int i = 0; i < size; ++i) { |
| rands[i] = rand.nextDouble(); |
| } |
| |
| double[] streamRands = new Random(0).doubles(size).toArray(); |
| assertTrue(Arrays.equals(rands, streamRands)); |
| assertEquals(size, new Random(0).doubles(size).count()); |
| |
| try { |
| new Random(0).ints(-1); |
| fail(); |
| } catch (IllegalArgumentException expected) {} |
| } |
| |
| public void test_doubles$II() { |
| final int limit = 128; // We can't test for every element in an infinite stream. |
| final int origin = 128, bound = 256; |
| |
| Random rand = new Random(0); |
| double[] rands = new double[limit]; |
| for(int i = 0; i < limit; ++i) { |
| double r = rand.nextDouble() * (bound - origin) + origin; |
| if (r >= bound) { |
| r = Math.nextDown(r); |
| } |
| rands[i] = r; |
| } |
| |
| double[] streamRands = new Random(0).doubles(origin, bound).limit(limit).toArray(); |
| assertTrue(Arrays.equals(rands, streamRands)); |
| |
| try { |
| new Random(0).doubles(100, 0); |
| fail(); |
| } catch (IllegalArgumentException expected) {} |
| } |
| |
| public void test_doubles$LII() { |
| final int size = 32; |
| final int origin = 128, bound = 256; |
| |
| Random rand = new Random(0); |
| double[] rands = new double[size]; |
| for(int i = 0; i < size; ++i) { |
| double r = rand.nextDouble() * (bound - origin) + origin; |
| if (r >= bound) { |
| r = Math.nextDown(r); |
| } |
| rands[i] = r; |
| } |
| |
| double[] streamRands = new Random(0).doubles(size, origin, bound).toArray(); |
| assertTrue(Arrays.equals(rands, streamRands)); |
| assertEquals(size, new Random(0).doubles(size, origin, bound).count()); |
| |
| try { |
| new Random(0).doubles(-1, 10, 20); |
| fail(); |
| } catch (IllegalArgumentException expected) {} |
| try { |
| new Random(0).doubles(10, 100, 0); |
| fail(); |
| } catch (IllegalArgumentException expected) {} |
| } |
| } |