Java tutorial
//package com.java2s; /* * 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. */ public class Main { /** * <p>Finds the first index in the {@code CharSequence} that matches the * specified character.</p> * * @param cs the {@code CharSequence} to be processed, not null * @param searchChar the char to be searched for * @param start the start index, negative starts at the string start * @return the index where the search char was found, -1 if not found */ static int indexOf(final CharSequence cs, final int searchChar, int start) { if (cs instanceof String) { return ((String) cs).indexOf(searchChar, start); } else { final int sz = cs.length(); if (start < 0) { start = 0; } for (int i = start; i < sz; i++) { if (cs.charAt(i) == searchChar) { return i; } } return -1; } } /** * Used by the indexOf(CharSequence methods) as a green implementation of indexOf. * * @param cs the {@code CharSequence} to be processed * @param searchChar the {@code CharSequence} to be searched for * @param start the start index * @return the index where the search sequence was found */ static int indexOf(final CharSequence cs, final CharSequence searchChar, final int start) { return cs.toString().indexOf(searchChar.toString(), start); // if (cs instanceof String && searchChar instanceof String) { // // TODO: Do we assume searchChar is usually relatively small; // // If so then calling toString() on it is better than reverting to // // the green implementation in the else block // return ((String) cs).indexOf((String) searchChar, start); // } else { // // TODO: Implement rather than convert to String // return cs.toString().indexOf(searchChar.toString(), start); // } } }