| /* |
| * Copyright (c) 1998, 2008, 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. |
| * |
| * 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. |
| */ |
| |
| /* |
| */ |
| |
| import java.io.*; |
| |
| class CompressOutputStream extends FilterOutputStream |
| implements CompressConstants |
| { |
| |
| public CompressOutputStream(OutputStream out) { |
| super(out); |
| } |
| |
| // buffer of 6-bit codes to pack into next 32-bit word |
| int buf[] = new int[5]; |
| |
| // number of valid codes pending in buffer |
| int bufPos = 0; |
| |
| public void write(int b) throws IOException { |
| b &= 0xFF; // force argument to a byte |
| |
| int pos = codeTable.indexOf((char)b); |
| if (pos != -1) |
| writeCode(BASE + pos); |
| else { |
| writeCode(RAW); |
| writeCode(b >> 4); |
| writeCode(b & 0xF); |
| } |
| } |
| |
| public void write(byte b[], int off, int len) throws IOException { |
| /* |
| * This is quite an inefficient implementation, because it has to |
| * call the other write method for every byte in the array. It |
| * could be optimized for performance by doing all the processing |
| * in this method. |
| */ |
| for (int i = 0; i < len; i++) |
| write(b[off + i]); |
| } |
| |
| public void flush() throws IOException { |
| while (bufPos > 0) |
| writeCode(NOP); |
| } |
| |
| private void writeCode(int c) throws IOException { |
| buf[bufPos++] = c; |
| if (bufPos == 5) { // write next word when we have 5 codes |
| int pack = (buf[0] << 24) | (buf[1] << 18) | (buf[2] << 12) | |
| (buf[3] << 6) | buf[4]; |
| out.write((pack >>> 24) & 0xFF); |
| out.write((pack >>> 16) & 0xFF); |
| out.write((pack >>> 8) & 0xFF); |
| out.write((pack >>> 0) & 0xFF); |
| bufPos = 0; |
| } |
| } |
| } |