1 /* 2 * Copyright (c) 2011, 2013, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package com.oracle.ipack.util; 27 28 import java.io.FilterOutputStream; 29 import java.io.IOException; 30 import java.io.OutputStream; 31 import java.security.MessageDigest; 32 import java.security.NoSuchAlgorithmException; 33 34 public class HashingOutputStream extends FilterOutputStream { 35 private final MessageDigest messageDigest; 36 37 public HashingOutputStream(final OutputStream out) { 38 super(out); 39 try { 40 messageDigest = MessageDigest.getInstance("SHA1"); 41 } catch (final NoSuchAlgorithmException e) { 42 throw new IllegalStateException("Can't create message digest", e); 43 } 44 } 45 46 @Override 47 public void write(final int byteValue) throws IOException { 48 out.write(byteValue); 49 messageDigest.update((byte) byteValue); 50 } 51 52 @Override 53 public void write(final byte[] buffer, final int offset, final int length) 54 throws IOException { 55 out.write(buffer, offset, length); 56 messageDigest.update(buffer, offset, length); 57 } 58 59 public byte[] calculateHash() { 60 return messageDigest.digest(); 61 } 62 }