Java tutorial
/* * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER. * * Copyright 1997-2007 Sun Microsystems, Inc. All rights reserved. * * The contents of this file are subject to the terms of either the GNU * General Public License Version 2 only ("GPL") or the Common Development * and Distribution License("CDDL") (collectively, the "License"). You * may not use this file except in compliance with the License. You can obtain * a copy of the License at https://glassfish.dev.java.net/public/CDDL+GPL.html * or glassfish/bootstrap/legal/LICENSE.txt. See the License for the specific * language governing permissions and limitations under the License. * * When distributing the software, include this License Header Notice in each * file and include the License file at glassfish/bootstrap/legal/LICENSE.txt. * Sun designates this particular file as subject to the "Classpath" exception * as provided by Sun in the GPL Version 2 section of the License file that * accompanied this code. If applicable, add the following below the License * Header, with the fields enclosed by brackets [] replaced by your own * identifying information: "Portions Copyrighted [year] * [name of copyright owner]" * * Contributor(s): * * If you wish your version of this file to be governed by only the CDDL or * only the GPL Version 2, indicate your decision by adding "[Contributor] * elects to include this software in this distribution under the [CDDL or GPL * Version 2] license." If you don't indicate a single choice of license, a * recipient has the option to distribute your version of this file under * either the CDDL, the GPL Version 2 or to extend the choice of license to * its licensees as provided above. However, if you add GPL Version 2 code * and therefore, elected the GPL Version 2 license, then the option applies * only if the new code is made subject to such option by the copyright * holder. */ /* * @(#)QPDecoderStream.java 1.11 07/05/04 */ import java.io.*; /** * This class implements a QP Decoder. It is implemented as * a FilterInputStream, so one can just wrap this class around * any input stream and read bytes from this filter. The decoding * is done as the bytes are read out. * * @author John Mani */ public class QPDecoderStream extends FilterInputStream { protected byte[] ba = new byte[2]; protected int spaces = 0; /** * Create a Quoted Printable decoder that decodes the specified * input stream. * @param in the input stream */ public QPDecoderStream(InputStream in) { super(new PushbackInputStream(in, 2)); // pushback of size=2 } /** * Read the next decoded byte from this input stream. The byte * is returned as an <code>int</code> in the range <code>0</code> * to <code>255</code>. If no byte is available because the end of * the stream has been reached, the value <code>-1</code> is returned. * This method blocks until input data is available, the end of the * stream is detected, or an exception is thrown. * * @return the next byte of data, or <code>-1</code> if the end of the * stream is reached. * @exception IOException if an I/O error occurs. */ public int read() throws IOException { if (spaces > 0) { // We have cached space characters, return one spaces--; return ' '; } int c = in.read(); if (c == ' ') { // Got space, keep reading till we get a non-space char while ((c = in.read()) == ' ') spaces++; if (c == '\r' || c == '\n' || c == -1) // If the non-space char is CR/LF/EOF, the spaces we got // so far is junk introduced during transport. Junk 'em. spaces = 0; else { // The non-space char is NOT CR/LF, the spaces are valid. ((PushbackInputStream) in).unread(c); c = ' '; } return c; // return either <SPACE> or <CR/LF> } else if (c == '=') { // QP Encoded atom. Decode the next two bytes int a = in.read(); if (a == '\n') { /* Hmm ... not really confirming QP encoding, but lets * allow this as a LF terminated encoded line .. and * consider this a soft linebreak and recurse to fetch * the next char. */ return read(); } else if (a == '\r') { // Expecting LF. This forms a soft linebreak to be ignored. int b = in.read(); if (b != '\n') /* Not really confirming QP encoding, but * lets allow this as well. */ ((PushbackInputStream) in).unread(b); return read(); } else if (a == -1) { // Not valid QP encoding, but we be nice and tolerant here ! return -1; } else { ba[0] = (byte) a; ba[1] = (byte) in.read(); try { return ASCIIUtility.parseInt(ba, 0, 2, 16); } catch (NumberFormatException nex) { /* System.err.println( "Illegal characters in QP encoded stream: " + ASCIIUtility.toString(ba, 0, 2) ); */ ((PushbackInputStream) in).unread(ba); return c; } } } return c; } /** * Reads up to <code>len</code> decoded bytes of data from this input stream * into an array of bytes. This method blocks until some input is * available. * <p> * * @param buf the buffer into which the data is read. * @param off the start offset of the data. * @param len the maximum number of bytes read. * @return the total number of bytes read into the buffer, or * <code>-1</code> if there is no more data because the end of * the stream has been reached. * @exception IOException if an I/O error occurs. */ public int read(byte[] buf, int off, int len) throws IOException { int i, c; for (i = 0; i < len; i++) { if ((c = read()) == -1) { if (i == 0) // At end of stream, so we should i = -1; // return -1 , NOT 0. break; } buf[off + i] = (byte) c; } return i; } /** * Tests if this input stream supports marks. Currently this class * does not support marks */ public boolean markSupported() { return false; } /** * Returns the number of bytes that can be read from this input * stream without blocking. The QP algorithm does not permit * a priori knowledge of the number of bytes after decoding, so * this method just invokes the <code>available</code> method * of the original input stream. */ public int available() throws IOException { // This is bogus ! We don't really know how much // bytes are available *after* decoding return in.available(); } /**** begin TEST program public static void main(String argv[]) throws Exception { FileInputStream infile = new FileInputStream(argv[0]); QPDecoderStream decoder = new QPDecoderStream(infile); int c; while ((c = decoder.read()) != -1) System.out.print((char)c); System.out.println(); } *** end TEST program ****/ } /* * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER. * * Copyright 1997-2007 Sun Microsystems, Inc. All rights reserved. * * The contents of this file are subject to the terms of either the GNU * General Public License Version 2 only ("GPL") or the Common Development * and Distribution License("CDDL") (collectively, the "License"). You * may not use this file except in compliance with the License. You can obtain * a copy of the License at https://glassfish.dev.java.net/public/CDDL+GPL.html * or glassfish/bootstrap/legal/LICENSE.txt. See the License for the specific * language governing permissions and limitations under the License. * * When distributing the software, include this License Header Notice in each * file and include the License file at glassfish/bootstrap/legal/LICENSE.txt. * Sun designates this particular file as subject to the "Classpath" exception * as provided by Sun in the GPL Version 2 section of the License file that * accompanied this code. If applicable, add the following below the License * Header, with the fields enclosed by brackets [] replaced by your own * identifying information: "Portions Copyrighted [year] * [name of copyright owner]" * * Contributor(s): * * If you wish your version of this file to be governed by only the CDDL or * only the GPL Version 2, indicate your decision by adding "[Contributor] * elects to include this software in this distribution under the [CDDL or GPL * Version 2] license." If you don't indicate a single choice of license, a * recipient has the option to distribute your version of this file under * either the CDDL, the GPL Version 2 or to extend the choice of license to * its licensees as provided above. However, if you add GPL Version 2 code * and therefore, elected the GPL Version 2 license, then the option applies * only if the new code is made subject to such option by the copyright * holder. */ /* * @(#)ASCIIUtility.java 1.11 07/05/04 */ class ASCIIUtility { // Private constructor so that this class is not instantiated private ASCIIUtility() { } /** * Convert the bytes within the specified range of the given byte * array into a signed integer in the given radix . The range extends * from <code>start</code> till, but not including <code>end</code>. <p> * * Based on java.lang.Integer.parseInt() */ public static int parseInt(byte[] b, int start, int end, int radix) throws NumberFormatException { if (b == null) throw new NumberFormatException("null"); int result = 0; boolean negative = false; int i = start; int limit; int multmin; int digit; if (end > start) { if (b[i] == '-') { negative = true; limit = Integer.MIN_VALUE; i++; } else { limit = -Integer.MAX_VALUE; } multmin = limit / radix; if (i < end) { digit = Character.digit((char) b[i++], radix); if (digit < 0) { throw new NumberFormatException("illegal number: " + toString(b, start, end)); } else { result = -digit; } } while (i < end) { // Accumulating negatively avoids surprises near MAX_VALUE digit = Character.digit((char) b[i++], radix); if (digit < 0) { throw new NumberFormatException("illegal number"); } if (result < multmin) { throw new NumberFormatException("illegal number"); } result *= radix; if (result < limit + digit) { throw new NumberFormatException("illegal number"); } result -= digit; } } else { throw new NumberFormatException("illegal number"); } if (negative) { if (i > start + 1) { return result; } else { /* Only got "-" */ throw new NumberFormatException("illegal number"); } } else { return -result; } } /** * Convert the bytes within the specified range of the given byte * array into a signed integer . The range extends from * <code>start</code> till, but not including <code>end</code>. <p> */ public static int parseInt(byte[] b, int start, int end) throws NumberFormatException { return parseInt(b, start, end, 10); } /** * Convert the bytes within the specified range of the given byte * array into a signed long in the given radix . The range extends * from <code>start</code> till, but not including <code>end</code>. <p> * * Based on java.lang.Long.parseLong() */ public static long parseLong(byte[] b, int start, int end, int radix) throws NumberFormatException { if (b == null) throw new NumberFormatException("null"); long result = 0; boolean negative = false; int i = start; long limit; long multmin; int digit; if (end > start) { if (b[i] == '-') { negative = true; limit = Long.MIN_VALUE; i++; } else { limit = -Long.MAX_VALUE; } multmin = limit / radix; if (i < end) { digit = Character.digit((char) b[i++], radix); if (digit < 0) { throw new NumberFormatException("illegal number: " + toString(b, start, end)); } else { result = -digit; } } while (i < end) { // Accumulating negatively avoids surprises near MAX_VALUE digit = Character.digit((char) b[i++], radix); if (digit < 0) { throw new NumberFormatException("illegal number"); } if (result < multmin) { throw new NumberFormatException("illegal number"); } result *= radix; if (result < limit + digit) { throw new NumberFormatException("illegal number"); } result -= digit; } } else { throw new NumberFormatException("illegal number"); } if (negative) { if (i > start + 1) { return result; } else { /* Only got "-" */ throw new NumberFormatException("illegal number"); } } else { return -result; } } /** * Convert the bytes within the specified range of the given byte * array into a signed long . The range extends from * <code>start</code> till, but not including <code>end</code>. <p> */ public static long parseLong(byte[] b, int start, int end) throws NumberFormatException { return parseLong(b, start, end, 10); } /** * Convert the bytes within the specified range of the given byte * array into a String. The range extends from <code>start</code> * till, but not including <code>end</code>. <p> */ public static String toString(byte[] b, int start, int end) { int size = end - start; char[] theChars = new char[size]; for (int i = 0, j = start; i < size;) theChars[i++] = (char) (b[j++] & 0xff); return new String(theChars); } public static String toString(ByteArrayInputStream is) { int size = is.available(); char[] theChars = new char[size]; byte[] bytes = new byte[size]; is.read(bytes, 0, size); for (int i = 0; i < size;) theChars[i] = (char) (bytes[i++] & 0xff); return new String(theChars); } public static byte[] getBytes(String s) { char[] chars = s.toCharArray(); int size = chars.length; byte[] bytes = new byte[size]; for (int i = 0; i < size;) bytes[i] = (byte) chars[i++]; return bytes; } public static byte[] getBytes(InputStream is) throws IOException { int len; int size = 1024; byte[] buf; if (is instanceof ByteArrayInputStream) { size = is.available(); buf = new byte[size]; len = is.read(buf, 0, size); } else { ByteArrayOutputStream bos = new ByteArrayOutputStream(); buf = new byte[size]; while ((len = is.read(buf, 0, size)) != -1) bos.write(buf, 0, len); buf = bos.toByteArray(); } return buf; } }