Here you can find the source of getDecoder(Charset charset)
protected static synchronized CharsetDecoder getDecoder(Charset charset) throws IllegalArgumentException
//package com.java2s; /** //from ww w . j a v a 2 s. c o m * Copyright 2011 The Buzz Media, LLC * * Licensed 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. */ import java.nio.charset.Charset; import java.nio.charset.CharsetDecoder; import java.util.Map; public class Main { protected static Map<Charset, CharsetDecoder> decoderMap; protected static synchronized CharsetDecoder getDecoder(Charset charset) throws IllegalArgumentException { if (charset == null) throw new IllegalArgumentException( "charset cannot be null, consider using one of the pre-defined Charset constants from this class for convenience."); CharsetDecoder result = decoderMap.get(charset); if (result == null) { result = charset.newDecoder(); decoderMap.put(charset, result); } return result; } }