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 { private static final String[] CHAR_STRING_ARRAY = new String[128]; /** * <p>Converts the character to a String that contains the one character.</p> * * <p>For ASCII 7 bit characters, this uses a cache that will return the * same String object each time.</p> * * <pre> * CharUtils.toString(' ') = " " * CharUtils.toString('A') = "A" * </pre> * * @param ch the character to convert * @return a String containing the one specified character */ public static String toString(final char ch) { if (ch < 128) { return CHAR_STRING_ARRAY[ch]; } return new String(new char[] { ch }); } /** * <p>Converts the character to a String that contains the one character.</p> * * <p>For ASCII 7 bit characters, this uses a cache that will return the * same String object each time.</p> * * <p>If {@code null} is passed in, {@code null} will be returned.</p> * * <pre> * CharUtils.toString(null) = null * CharUtils.toString(' ') = " " * CharUtils.toString('A') = "A" * </pre> * * @param ch the character to convert * @return a String containing the one specified character */ public static String toString(final Character ch) { if (ch == null) { return null; } return toString(ch.charValue()); } }