| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You 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 org.apache.solr.common.util; |
| |
| import org.apache.solr.SolrTestCase; |
| |
| import java.util.Random; |
| |
| /** Tests for lookup3ycs hash functions |
| */ |
| public class TestHash extends SolrTestCase { |
| |
| // Test that the java version produces the same output as the C version |
| public void testEqualsLOOKUP3() { |
| int[] hashes = new int[] {0xc4c20dd5,0x3ab04cc3,0xebe874a3,0x0e770ef3,0xec321498,0x73845e86,0x8a2db728,0x03c313bb,0xfe5b9199,0x95965125,0xcbc4e7c2}; |
| /*** the hash values were generated by adding the following to lookup3.c |
| * |
| * char* s = "hello world"; |
| * int len = strlen(s); |
| * uint32_t a[len]; |
| * for (int i=0; i<len; i++) { |
| * a[i]=s[i]; |
| * uint32_t result = hashword(a, i+1, i*12345); |
| * printf("0x%.8x\n", result); |
| * } |
| * |
| */ |
| |
| String s = "hello world"; |
| int[] a = new int[s.length()]; |
| for (int i=0; i<s.length(); i++) { |
| a[i] = s.charAt(i); |
| int len = i+1; |
| int hash = Hash.lookup3(a, 0, len, i*12345); |
| assertEquals(hashes[i], hash); |
| int hash2 = Hash.lookup3ycs(a, 0, len, i*12345+(len<<2)); |
| assertEquals(hashes[i], hash2); |
| int hash3 = Hash.lookup3ycs(s, 0, len, i*12345+(len<<2)); |
| assertEquals(hashes[i], hash3); |
| } |
| } |
| |
| |
| // test that the hash of the UTF-16 encoded Java String is equal to the hash of the unicode code points |
| void tstEquiv(int[] utf32, int len) { |
| int seed=100; |
| StringBuilder sb = new StringBuilder(); |
| for (int i=0; i<len; i++) sb.appendCodePoint(utf32[i]); |
| int hash = Hash.lookup3(utf32, 0, len, seed -(len<<2)); |
| int hash2 = Hash.lookup3ycs(utf32, 0, len, seed); |
| assertEquals(hash, hash2); |
| int hash3 = Hash.lookup3ycs(sb, 0, sb.length(), seed); |
| assertEquals(hash, hash3); |
| long hash4 = Hash.lookup3ycs64(sb, 0, sb.length(), seed); |
| assertEquals((int)hash4, hash); |
| } |
| |
| |
| public void testHash() { |
| Random r = random(); |
| int[] utf32 = new int[20]; |
| tstEquiv(utf32,0); |
| |
| utf32[0]=0x10000; |
| tstEquiv(utf32,1); |
| utf32[0]=0x8000; |
| tstEquiv(utf32,1); |
| utf32[0]=Character.MAX_CODE_POINT; |
| tstEquiv(utf32,1); |
| |
| for (int iter=0; iter<10000; iter++) { |
| int len = r.nextInt(utf32.length+1); |
| for (int i=0; i<len; i++) { |
| int codePoint; |
| do { |
| codePoint = r.nextInt(Character.MAX_CODE_POINT+1); |
| } while((codePoint & 0xF800) == 0xD800); // avoid surrogate code points |
| utf32[i] = codePoint; |
| } |
| // System.out.println("len="+len + ","+utf32[0]+","+utf32[1]); |
| tstEquiv(utf32, len); |
| } |
| } |
| |
| |
| } |