001 /** 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017 package org.fusesource.hawtdb.api; 018 019 020 /** 021 * StringPrefixer is a {@link Prefixer} implementation that works on strings. 022 * 023 * @author <a href="http://hiramchirino.com">Hiram Chirino</a> 024 */ 025 public class StringPrefixer implements Prefixer<String> { 026 027 /** 028 * Example: If value1 is "Hello World" and value 2 is "Help Me" then the 029 * result will be: "Help" 030 * 031 * @see Prefixer#getSimplePrefix 032 */ 033 public String getSimplePrefix(String value1, String value2) { 034 char[] c1 = value1.toCharArray(); 035 char[] c2 = value2.toCharArray(); 036 int n = Math.min(c1.length, c2.length); 037 int i = 0; 038 while (i < n) { 039 if (c1[i] != c2[i]) { 040 return value2.substring(0, i + 1); 041 } 042 i++; 043 } 044 045 if (n == c2.length) { 046 return value2; 047 } 048 return value2.substring(0, n); 049 } 050 }