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Diffstat (limited to 'libjava/classpath/java/io/FilterReader.java')
| -rw-r--r-- | libjava/classpath/java/io/FilterReader.java | 185 |
1 files changed, 185 insertions, 0 deletions
diff --git a/libjava/classpath/java/io/FilterReader.java b/libjava/classpath/java/io/FilterReader.java new file mode 100644 index 00000000000..2bd040a7f72 --- /dev/null +++ b/libjava/classpath/java/io/FilterReader.java @@ -0,0 +1,185 @@ +/* FilterReader.java -- Base class for char stream classes that filter input + Copyright (C) 1998, 1999, 2001, 2003, 2005 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 java.io; + +/* Written using "Java Class Libraries", 2nd edition, ISBN 0-201-31002-3 + * "The Java Language Specification", ISBN 0-201-63451-1 + * plus online API docs for JDK 1.2 beta from http://www.javasoft.com. + * Status: Believed complete and correct. + */ + +/** + * This is the common superclass of all standard classes that filter + * input. It acts as a layer on top of an underlying <code>Reader</code> + * and simply redirects calls made to it to the subordinate Reader + * instead. Subclasses of this class perform additional filtering + * functions in addition to simply redirecting the call. + * <p> + * When creating a subclass of <code>FilterReader</code>, override the + * appropriate methods to implement the desired filtering. However, note + * that the <code>read(char[])</code> method does not need to be overridden + * as this class redirects calls to that method to + * <code>read(yte[], int, int)</code> instead of to the subordinate + * <code>Reader} read(yte[])</code> method. + * + * @author Aaron M. Renn (arenn@urbanophile.com) + * @author Warren Levy (warrenl@cygnus.com) + */ +public abstract class FilterReader extends Reader +{ + /** + * This is the subordinate <code>Reader</code> to which method calls + * are redirected + */ + protected Reader in; + + /** + * Create a <code>FilterReader</code> with the specified subordinate + * <code>Reader</code>. + * The <code>lock</code> of the new <code>FilterReader</code> will be set + * to <code>in.lock</code>. + * + * @param in The subordinate <code>Reader</code> + */ + protected FilterReader(Reader in) + { + super(in.lock); + this.in = in; + } + + /** + * Calls the <code>in.mark(int)</code> method. + * + * @param readlimit The parameter passed to <code>in.mark(int)</code> + * + * @exception IOException If an error occurs + */ + public void mark(int readlimit) throws IOException + { + in.mark(readlimit); + } + + /** + * Calls the <code>in.markSupported()</code> method. + * + * @return <code>true</code> if mark/reset is supported, + * <code>false</code> otherwise + */ + public boolean markSupported() + { + return(in.markSupported()); + } + + /** + * Calls the <code>in.reset()</code> method. + * + * @exception IOException If an error occurs + */ + public void reset() throws IOException + { + in.reset(); + } + + /** + * Calls the <code>in.read()</code> method. + * + * @return The value returned from <code>in.available()</code> + * + * @exception IOException If an error occurs + */ + public boolean ready() throws IOException + { + return(in.ready()); + } + + /** + * Calls the <code>in.skip(long)</code> method + * + * @param numBytes The requested number of chars to skip. + * + * @return The value returned from <code>in.skip(long)</code> + * + * @exception IOException If an error occurs + */ + public long skip(long num_chars) throws IOException + { + return(in.skip(num_chars)); + } + + /** + * Calls the <code>in.read()</code> method + * + * @return The value returned from <code>in.read()</code> + * + * @exception IOException If an error occurs + */ + public int read() throws IOException + { + return(in.read()); + } + + /** + * Calls the <code>in.read(char[], int, int)</code> method. + * + * @param buf The buffer to read chars into + * @param offset The index into the buffer to start storing chars + * @param len The maximum number of chars to read. + * + * @return The value retured from <code>in.read(char[], int, int)</code> + * + * @exception IOException If an error occurs + */ + public int read(char[] buf, int offset, int len) throws IOException + { + return(in.read(buf, offset, len)); + } + + /** + * This method closes the stream by calling the <code>close()</code> method + * of the underlying stream. + * + * @exception IOException If an error occurs + */ + public void close() throws IOException + { + in.close(); + } + +} // class FilterReader + |