| /* gnu/regexp/REFilterInputStream.java |
| Copyright (C) 1998-2001, 2004 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., 51 Franklin Street, Fifth Floor, Boston, MA |
| 02110-1301 USA. |
| |
| Linking this library statically or dynamically with other modules is |
| making a combined work based on this library. Thus, the terms and |
| conditions of the GNU General Public License cover the whole |
| combination. |
| |
| As a special exception, the copyright holders of this library give you |
| permission to link this library with independent modules to produce an |
| executable, regardless of the license terms of these independent |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
| this exception to your version of the library, but you are not |
| obligated to do so. If you do not wish to do so, delete this |
| exception statement from your version. */ |
| |
| |
| package gnu.java.util.regex; |
| import java.io.FilterInputStream; |
| import java.io.InputStream; |
| |
| /** |
| * Replaces instances of a given RE found within an InputStream |
| * with replacement text. The replacements are interpolated into the |
| * stream when a match is found. |
| * |
| * @author <A HREF="mailto:wes@cacas.org">Wes Biggs</A> |
| * @deprecated This class cannot properly handle all character |
| * encodings. For proper handling, use the REFilterReader |
| * class instead. |
| */ |
| |
| public class REFilterInputStream extends FilterInputStream { |
| |
| private RE expr; |
| private String replace; |
| private String buffer; |
| private int bufpos; |
| private int offset; |
| private CharIndexedInputStream stream; |
| |
| /** |
| * Creates an REFilterInputStream. When reading from this stream, |
| * occurrences of patterns matching the supplied regular expression |
| * will be replaced with the supplied replacement text (the |
| * metacharacters $0 through $9 may be used to refer to the full |
| * match or subexpression matches). |
| * |
| * @param stream The InputStream to be filtered. |
| * @param expr The regular expression to search for. |
| * @param replace The text pattern to replace matches with. |
| */ |
| public REFilterInputStream(InputStream stream, RE expr, String replace) { |
| super(stream); |
| this.stream = new CharIndexedInputStream(stream,0); |
| this.expr = expr; |
| this.replace = replace; |
| } |
| |
| /** |
| * Reads the next byte from the stream per the general contract of |
| * InputStream.read(). Returns -1 on error or end of stream. |
| */ |
| public int read() { |
| // If we have buffered replace data, use it. |
| if ((buffer != null) && (bufpos < buffer.length())) { |
| return (int) buffer.charAt(bufpos++); |
| } |
| |
| // check if input is at a valid position |
| if (!stream.isValid()) return -1; |
| |
| REMatch mymatch = new REMatch(expr.getNumSubs(),offset,0); |
| if (expr.match(stream, mymatch)) { |
| mymatch.end[0] = mymatch.index; |
| mymatch.finish(stream); |
| stream.move(mymatch.toString().length()); |
| offset += mymatch.toString().length(); |
| buffer = mymatch.substituteInto(replace); |
| bufpos = 1; |
| |
| // This is prone to infinite loops if replace string turns out empty. |
| if (buffer.length() > 0) { |
| return buffer.charAt(0); |
| } |
| } |
| char ch = stream.charAt(0); |
| if (ch == CharIndexed.OUT_OF_BOUNDS) return -1; |
| stream.move(1); |
| offset++; |
| return ch; |
| } |
| |
| /** |
| * Returns false. REFilterInputStream does not support mark() and |
| * reset() methods. |
| */ |
| public boolean markSupported() { |
| return false; |
| } |
| |
| /** Reads from the stream into the provided array. */ |
| public int read(byte[] b, int off, int len) { |
| int i; |
| int ok = 0; |
| while (len-- > 0) { |
| i = read(); |
| if (i == -1) return (ok == 0) ? -1 : ok; |
| b[off++] = (byte) i; |
| ok++; |
| } |
| return ok; |
| } |
| |
| /** Reads from the stream into the provided array. */ |
| public int read(byte[] b) { |
| return read(b,0,b.length); |
| } |
| } |