Java tutorial
/* * 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. */ /* $Id: ASCIIHexOutputStream.java 426584 2006-07-28 16:01:47Z jeremias $ */ import java.io.OutputStream; import java.io.FilterOutputStream; import java.io.IOException; /** * This class applies a ASCII Hex encoding to the stream. * * @version $Id: ASCIIHexOutputStream.java 426584 2006-07-28 16:01:47Z jeremias $ */ public class ASCIIHexOutputStream extends FilterOutputStream { private static final int EOL = 0x0A; //"\n" private static final int EOD = 0x3E; //">" private static final int ZERO = 0x30; //"0" private static final int NINE = 0x39; //"9" private static final int A = 0x41; //"A" private static final int ADIFF = A - NINE - 1; private int posinline = 0; /** @see java.io.FilterOutputStream **/ public ASCIIHexOutputStream(OutputStream out) { super(out); } /** @see java.io.FilterOutputStream **/ public void write(int b) throws IOException { b &= 0xFF; int digit1 = ((b & 0xF0) >> 4) + ZERO; if (digit1 > NINE) { digit1 += ADIFF; } out.write(digit1); int digit2 = (b & 0x0F) + ZERO; if (digit2 > NINE) { digit2 += ADIFF; } out.write(digit2); posinline++; checkLineWrap(); } private void checkLineWrap() throws IOException { //Maximum line length is 80 characters if (posinline >= 40) { out.write(EOL); posinline = 0; } } /** @see Finalizable **/ public void finalizeStream() throws IOException { checkLineWrap(); //Write closing character ">" super.write(EOD); flush(); } /** @see java.io.FilterOutputStream **/ public void close() throws IOException { finalizeStream(); super.close(); } }