| /* |
| * Copyright (c) 1996, 2013, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package java.security; |
| |
| import java.io.IOException; |
| import java.io.EOFException; |
| import java.io.OutputStream; |
| import java.io.FilterOutputStream; |
| import java.io.PrintStream; |
| import java.io.ByteArrayOutputStream; |
| |
| /** |
| * A transparent stream that updates the associated message digest using |
| * the bits going through the stream. |
| * |
| * <p>To complete the message digest computation, call one of the |
| * {@code digest} methods on the associated message |
| * digest after your calls to one of this digest output stream's |
| * {@link #write(int) write} methods. |
| * |
| * <p>It is possible to turn this stream on or off (see |
| * {@link #on(boolean) on}). When it is on, a call to one of the |
| * {@code write} methods results in |
| * an update on the message digest. But when it is off, the message |
| * digest is not updated. The default is for the stream to be on. |
| * |
| * @see MessageDigest |
| * @see DigestInputStream |
| * |
| * @author Benjamin Renaud |
| * @since 1.2 |
| */ |
| public class DigestOutputStream extends FilterOutputStream { |
| |
| private boolean on = true; |
| |
| /** |
| * The message digest associated with this stream. |
| */ |
| protected MessageDigest digest; |
| |
| /** |
| * Creates a digest output stream, using the specified output stream |
| * and message digest. |
| * |
| * @param stream the output stream. |
| * |
| * @param digest the message digest to associate with this stream. |
| */ |
| public DigestOutputStream(OutputStream stream, MessageDigest digest) { |
| super(stream); |
| setMessageDigest(digest); |
| } |
| |
| /** |
| * Returns the message digest associated with this stream. |
| * |
| * @return the message digest associated with this stream. |
| * @see #setMessageDigest(java.security.MessageDigest) |
| */ |
| public MessageDigest getMessageDigest() { |
| return digest; |
| } |
| |
| /** |
| * Associates the specified message digest with this stream. |
| * |
| * @param digest the message digest to be associated with this stream. |
| * @see #getMessageDigest() |
| */ |
| public void setMessageDigest(MessageDigest digest) { |
| this.digest = digest; |
| } |
| |
| /** |
| * Updates the message digest (if the digest function is on) using |
| * the specified byte, and in any case writes the byte |
| * to the output stream. That is, if the digest function is on |
| * (see {@link #on(boolean) on}), this method calls |
| * {@code update} on the message digest associated with this |
| * stream, passing it the byte {@code b}. This method then |
| * writes the byte to the output stream, blocking until the byte |
| * is actually written. |
| * |
| * @param b the byte to be used for updating and writing to the |
| * output stream. |
| * |
| * @exception IOException if an I/O error occurs. |
| * |
| * @see MessageDigest#update(byte) |
| */ |
| public void write(int b) throws IOException { |
| out.write(b); |
| if (on) { |
| digest.update((byte)b); |
| } |
| } |
| |
| /** |
| * Updates the message digest (if the digest function is on) using |
| * the specified subarray, and in any case writes the subarray to |
| * the output stream. That is, if the digest function is on (see |
| * {@link #on(boolean) on}), this method calls {@code update} |
| * on the message digest associated with this stream, passing it |
| * the subarray specifications. This method then writes the subarray |
| * bytes to the output stream, blocking until the bytes are actually |
| * written. |
| * |
| * @param b the array containing the subarray to be used for updating |
| * and writing to the output stream. |
| * |
| * @param off the offset into {@code b} of the first byte to |
| * be updated and written. |
| * |
| * @param len the number of bytes of data to be updated and written |
| * from {@code b}, starting at offset {@code off}. |
| * |
| * @exception IOException if an I/O error occurs. |
| * |
| * @see MessageDigest#update(byte[], int, int) |
| */ |
| public void write(byte[] b, int off, int len) throws IOException { |
| out.write(b, off, len); |
| if (on) { |
| digest.update(b, off, len); |
| } |
| } |
| |
| /** |
| * Turns the digest function on or off. The default is on. When |
| * it is on, a call to one of the {@code write} methods results in an |
| * update on the message digest. But when it is off, the message |
| * digest is not updated. |
| * |
| * @param on true to turn the digest function on, false to turn it |
| * off. |
| */ |
| public void on(boolean on) { |
| this.on = on; |
| } |
| |
| /** |
| * Prints a string representation of this digest output stream and |
| * its associated message digest object. |
| */ |
| public String toString() { |
| return "[Digest Output Stream] " + digest.toString(); |
| } |
| } |