| /* InflaterInputStream.java - Input stream filter for decompressing |
| Copyright (C) 1999, 2000 Free Software Foundation, Inc. |
| |
| This file is part of GNU Classpath. |
| |
| GNU Classpath is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2, or (at your option) |
| any later version. |
| |
| GNU Classpath 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 for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU Classpath; see the file COPYING. If not, write to the |
| Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 02111-1307 USA. |
| |
| As a special exception, if you link this library with other files to |
| produce an executable, this library does not by itself cause the |
| resulting executable to be covered by the GNU General Public License. |
| This exception does not however invalidate any other reasons why the |
| executable file might be covered by the GNU General Public License. */ |
| |
| package java.util.zip; |
| |
| import java.io.FilterInputStream; |
| import java.io.InputStream; |
| import java.io.IOException; |
| |
| /** |
| * @author Tom Tromey |
| * @date May 17, 1999 |
| */ |
| |
| /* Written using on-line Java Platform 1.2 API Specification |
| * and JCL book. |
| * Believed complete and correct. |
| */ |
| |
| public class InflaterInputStream extends FilterInputStream |
| { |
| protected void fill () throws IOException |
| { |
| len = in.read(buf, 0, buf.length); |
| if (len != -1) |
| inf.setInput(buf, 0, len); |
| } |
| |
| public InflaterInputStream (InputStream in) |
| { |
| this (in, new Inflater (), 512); |
| } |
| |
| public InflaterInputStream (InputStream in, Inflater infl) |
| { |
| this (in, infl, 512); |
| } |
| |
| public InflaterInputStream (InputStream in, Inflater infl, int bufsize) |
| { |
| super (in); |
| this.inf = infl; |
| this.buf = new byte[bufsize]; |
| } |
| |
| public int read () throws IOException |
| { |
| byte[] buf = new byte[1]; |
| int r = read (buf, 0, 1); |
| if (r != -1) |
| r = buf[0] & 0xff; |
| return r; |
| } |
| |
| public int read (byte[] buf, int off, int len) throws IOException |
| { |
| if (inf == null) |
| throw new IOException ("stream closed"); |
| if (inf.finished()) |
| return -1; |
| if (inf.needsInput()) |
| fill (); |
| int count; |
| try |
| { |
| count = inf.inflate(buf, off, len); |
| if (count == 0) |
| { |
| if (this.len == -1) |
| return -1; // Couldn't get any more data to feed to the Inflater |
| if (inf.needsDictionary()) |
| throw new ZipException ("Inflater needs Dictionary"); |
| } |
| } |
| catch (DataFormatException dfe) |
| { |
| throw new ZipException (dfe.getMessage()); |
| } |
| return count; |
| } |
| |
| public void close () throws IOException |
| { |
| inf = null; |
| super.close (); |
| } |
| |
| public int available () throws IOException |
| { |
| // According to the JDK 1.2 docs, this should only ever return 0 |
| // or 1 and should not be relied upon by Java programs. |
| if (inf == null) |
| throw new IOException ("stream closed"); |
| return inf.finished () ? 0 : 1; |
| } |
| |
| public long skip (long n) throws IOException |
| { |
| if (inf == null) |
| throw new IOException ("stream closed"); |
| |
| if (n == 0) |
| return 0; |
| |
| int min = (int) Math.min(n, 1024); |
| byte[] buf = new byte[min]; |
| |
| long s = 0; |
| while (n > 0) |
| { |
| int r = read (buf, 0, min); |
| if (r == -1) |
| break; |
| n -= r; |
| s += r; |
| min = (int) Math.min(n, 1024); |
| } |
| |
| return s; |
| } |
| |
| // Buffer for delivering uncompressed data to inflater. |
| protected byte[] buf; |
| |
| // Inflater used to decompress data. |
| protected Inflater inf; |
| |
| // Number of read bytes in buf. |
| protected int len; |
| } |