2362N/A * Copyright (c) 1996, 1999, Oracle and/or its affiliates. All rights reserved. 0N/A * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 0N/A * This code is free software; you can redistribute it and/or modify it 0N/A * under the terms of the GNU General Public License version 2 only, as 2362N/A * published by the Free Software Foundation. Oracle designates this 0N/A * particular file as subject to the "Classpath" exception as provided 2362N/A * by Oracle in the LICENSE file that accompanied this code. 0N/A * This code is distributed in the hope that it will be useful, but WITHOUT 0N/A * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 0N/A * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 0N/A * version 2 for more details (a copy is included in the LICENSE file that 0N/A * accompanied this code). 0N/A * You should have received a copy of the GNU General Public License version 0N/A * 2 along with this work; if not, write to the Free Software Foundation, 0N/A * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 2362N/A * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 2362N/A * or visit www.oracle.com if you need additional information or have any 0N/A * A transparent stream that updates the associated message digest using 0N/A * the bits going through the stream. 0N/A * <p>To complete the message digest computation, call one of the 0N/A * <code>digest</code> methods on the associated message 0N/A * digest after your calls to one of this digest input stream's 0N/A * {@link #read() read} methods. 0N/A * <p>It is possible to turn this stream on or off (see 0N/A * {@link #on(boolean) on}). When it is on, a call to one of the 0N/A * <code>read</code> methods 0N/A * results in an update on the message digest. But when it is off, 0N/A * the message digest is not updated. The default is for the stream 0N/A * <p>Note that digest objects can compute only one digest (see 0N/A * {@link MessageDigest}), 0N/A * so that in order to compute intermediate digests, a caller should 0N/A * retain a handle onto the digest object, and clone it for each 0N/A * digest to be computed, leaving the orginal digest untouched. 0N/A * @see MessageDigest 0N/A * @see DigestOutputStream 0N/A * @author Benjamin Renaud 0N/A /* NOTE: This should be made a generic UpdaterInputStream */ 0N/A /* Are we on or off? */ 0N/A private boolean on =
true;
0N/A * The message digest associated with this stream. 0N/A * Creates a digest input stream, using the specified input stream 0N/A * and message digest. 0N/A * @param stream the input stream. 0N/A * @param digest the message digest to associate with this stream. 0N/A * Returns the message digest associated with this stream. 0N/A * @return the message digest associated with this stream. 0N/A * @see #setMessageDigest(java.security.MessageDigest) 0N/A * Associates the specified message digest with this stream. 0N/A * @param digest the message digest to be associated with this stream. 0N/A * @see #getMessageDigest() 0N/A * Reads a byte, and updates the message digest (if the digest 0N/A * function is on). That is, this method reads a byte from the 0N/A * input stream, blocking until the byte is actually read. If the 0N/A * digest function is on (see {@link #on(boolean) on}), this method 0N/A * will then call <code>update</code> on the message digest associated 0N/A * with this stream, passing it the byte read. 0N/A * @return the byte read. 0N/A * @exception IOException if an I/O error occurs. 0N/A * @see MessageDigest#update(byte) 0N/A * Reads into a byte array, and updates the message digest (if the 0N/A * digest function is on). That is, this method reads up to 0N/A * <code>len</code> bytes from the input stream into the array 0N/A * <code>b</code>, starting at offset <code>off</code>. This method 0N/A * blocks until the data is actually 0N/A * read. If the digest function is on (see 0N/A * {@link #on(boolean) on}), this method will then call <code>update</code> 0N/A * on the message digest associated with this stream, passing it 0N/A * @param b the array into which the data is read. 0N/A * @param off the starting offset into <code>b</code> of where the 0N/A * data should be placed. 0N/A * @param len the maximum number of bytes to be read from the input 0N/A * stream into b, starting at offset <code>off</code>. 0N/A * @return the actual number of bytes read. This is less than 0N/A * <code>len</code> if the end of the stream is reached prior to 0N/A * reading <code>len</code> bytes. -1 is returned if no bytes were 0N/A * read because the end of the stream had already been reached when 0N/A * the call was made. 0N/A * @exception IOException if an I/O error occurs. 0N/A * @see MessageDigest#update(byte[], int, int) 0N/A * Turns the digest function on or off. The default is on. When 0N/A * it is on, a call to one of the <code>read</code> methods results in an 0N/A * update on the message digest. But when it is off, the message 0N/A * digest is not updated. 0N/A * @param on true to turn the digest function on, false to turn 0N/A * Prints a string representation of this digest input stream and 0N/A * its associated message digest object.