| /* |
| * Copyright (C) 2008 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 android.core; |
| |
| import junit.framework.TestCase; |
| |
| import java.util.zip.Adler32; |
| import java.util.zip.CRC32; |
| import android.test.suitebuilder.annotation.SmallTest; |
| |
| /** |
| * tests for CRC32 and Adler32 checksum algorithms. |
| */ |
| public class ChecksumTest extends TestCase { |
| |
| @SmallTest |
| public void testChecksum() throws Exception { |
| /* |
| * Values computed experimentally, using C interfaces. |
| */ |
| adler32Test(mTestString, 0x9de210dbL); |
| cRC32Test(mTestString, 0x939f04afL); |
| |
| // Test for issue 1016037 |
| wrongChecksumWithAdler32Test(); |
| } |
| |
| private void adler32Test(byte[] values, long expected) { |
| Adler32 adler = new Adler32(); |
| |
| // try it all at once |
| adler.update(values); |
| assertEquals(adler.getValue(), expected); |
| |
| // try resetting and computing one byte at a time |
| adler.reset(); |
| for (int i = 0; i < values.length; i++) { |
| adler.update(values[i]); |
| } |
| assertEquals(adler.getValue(), expected); |
| } |
| |
| private void cRC32Test(byte[] values, long expected) { |
| CRC32 crc = new CRC32(); |
| |
| // try it all at once |
| crc.update(values); |
| assertEquals(crc.getValue(), expected); |
| |
| // try resetting and computing one byte at a time |
| crc.reset(); |
| for (int i = 0; i < values.length; i++) { |
| crc.update(values[i]); |
| } |
| assertEquals(crc.getValue(), expected); |
| } |
| |
| // "The quick brown fox jumped over the lazy dogs\n" |
| private static byte[] mTestString = { |
| 0x54, 0x68, 0x65, 0x20, 0x71, 0x75, 0x69, 0x63, |
| 0x6b, 0x20, 0x62, 0x72, 0x6f, 0x77, 0x6e, 0x20, |
| 0x66, 0x6f, 0x78, 0x20, 0x6a, 0x75, 0x6d, 0x70, |
| 0x65, 0x64, 0x20, 0x6f, 0x76, 0x65, 0x72, 0x20, |
| 0x74, 0x68, 0x65, 0x20, 0x6c, 0x61, 0x7a, 0x79, |
| 0x20, 0x64, 0x6f, 0x67, 0x73, 0x2e, 0x0a |
| }; |
| |
| |
| // Test for issue 1016037 |
| private void wrongChecksumWithAdler32Test() { |
| byte[] bytes = {1, 0, 5, 0, 15, 0, 1, 11, 0, 1}; |
| Adler32 adler = new Adler32(); |
| adler.update(bytes); |
| long arrayChecksum = adler.getValue(); |
| adler.reset(); |
| for (int i = 0; i < bytes.length; i++) { |
| adler.update(bytes[i]); |
| } |
| assertEquals("Checksums not equal: expected: " + arrayChecksum + |
| " actual: " + adler.getValue(), arrayChecksum, adler.getValue()); |
| } |
| } |
| |