1 /* 2 * Copyright (C) 2012 The Guava Authors 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except 5 * in compliance with the License. You may obtain a copy of the License at 6 * 7 * http://www.apache.org/licenses/LICENSE-2.0 8 * 9 * Unless required by applicable law or agreed to in writing, software distributed under the License 10 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express 11 * or implied. See the License for the specific language governing permissions and limitations under 12 * the License. 13 */ 14 15 package com.google.common.hash; 16 17 import static com.google.common.hash.Hashing.ChecksumType.ADLER_32; 18 import static com.google.common.hash.Hashing.ChecksumType.CRC_32; 19 20 import java.util.zip.Checksum; 21 import junit.framework.TestCase; 22 23 /** 24 * Tests for ChecksumHashFunction. 25 * 26 * @author Colin Decker 27 */ 28 public class ChecksumHashFunctionTest extends TestCase { 29 testCrc32_equalsChecksumValue()30 public void testCrc32_equalsChecksumValue() throws Exception { 31 assertChecksum(CRC_32, ""); 32 assertChecksum(CRC_32, "Z"); 33 assertChecksum(CRC_32, "foobar"); 34 } 35 testAdler32_equalsChecksumValue()36 public void testAdler32_equalsChecksumValue() throws Exception { 37 assertChecksum(ADLER_32, ""); 38 assertChecksum(ADLER_32, "Z"); 39 assertChecksum(ADLER_32, "foobar"); 40 } 41 testCrc32_knownValues()42 public void testCrc32_knownValues() throws Exception { 43 assertHash32(0x1C8600E3, CRC_32, "hell"); 44 assertHash32(0x3610A686, CRC_32, "hello"); 45 assertHash32(0xED81F9F6, CRC_32, "hello "); 46 assertHash32(0x4850DDC2, CRC_32, "hello w"); 47 assertHash32(0x7A2D6005, CRC_32, "hello wo"); 48 assertHash32(0x1C192672, CRC_32, "hello wor"); 49 assertHash32(0x414FA339, CRC_32, "The quick brown fox jumps over the lazy dog"); 50 assertHash32(0x4400B5BC, CRC_32, "The quick brown fox jumps over the lazy cog"); 51 } 52 testAdler32_knownValues()53 public void testAdler32_knownValues() throws Exception { 54 assertHash32(0x041701A6, ADLER_32, "hell"); 55 assertHash32(0x062C0215, ADLER_32, "hello"); 56 assertHash32(0x08610235, ADLER_32, "hello "); 57 assertHash32(0x0B0D02AC, ADLER_32, "hello w"); 58 assertHash32(0x0E28031B, ADLER_32, "hello wo"); 59 assertHash32(0x11B5038D, ADLER_32, "hello wor"); 60 assertHash32(0x5BDC0FDA, ADLER_32, "The quick brown fox jumps over the lazy dog"); 61 assertHash32(0x5BD90FD9, ADLER_32, "The quick brown fox jumps over the lazy cog"); 62 } 63 assertChecksum(ImmutableSupplier<Checksum> supplier, String input)64 private static void assertChecksum(ImmutableSupplier<Checksum> supplier, String input) { 65 byte[] bytes = HashTestUtils.ascii(input); 66 67 Checksum checksum = supplier.get(); 68 checksum.update(bytes, 0, bytes.length); 69 long value = checksum.getValue(); 70 71 String toString = "name"; 72 HashFunction func = new ChecksumHashFunction(supplier, 32, toString); 73 assertEquals(toString, func.toString()); 74 assertEquals(value, func.hashBytes(bytes).padToLong()); 75 } 76 assertHash32( int expected, ImmutableSupplier<Checksum> supplier, String input)77 private static void assertHash32( 78 int expected, ImmutableSupplier<Checksum> supplier, String input) { 79 byte[] bytes = HashTestUtils.ascii(input); 80 String toString = "name"; 81 HashFunction func = new ChecksumHashFunction(supplier, 32, toString); 82 assertEquals(expected, func.hashBytes(bytes).asInt()); 83 assertEquals(toString, func.toString()); 84 } 85 } 86