| /* FilterInputStream.java -- Base class for classes that filter input |
| Copyright (C) 1998, 1999, 2001, 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., 59 Temple Place, Suite 330, Boston, MA |
| 02111-1307 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>InputStream</code> |
| * and simply redirects calls made to it to the subordinate InputStream |
| * instead. Subclasses of this class perform additional filtering |
| * functions in addition to simply redirecting the call. |
| * <p> |
| * This class is not abstract. However, since it only redirects calls |
| * to a subordinate <code>InputStream</code> without adding any functionality |
| * on top of it, this class should not be used directly. Instead, various |
| * subclasses of this class should be used. This is enforced with a |
| * protected constructor. Do not try to hack around it. |
| * <p> |
| * When creating a subclass of <code>FilterInputStream</code>, override the |
| * appropriate methods to implement the desired filtering. However, note |
| * that the <code>read(byte[])</code> method does not need to be overridden |
| * as this class redirects calls to that method to |
| * <code>read(byte[], int, int)</code> instead of to the subordinate |
| * <code>InputStream read(byte[])</code> method. |
| * |
| * @author Aaron M. Renn (arenn@urbanophile.com) |
| * @author Warren Levy (warrenl@cygnus.com) |
| */ |
| public class FilterInputStream extends InputStream |
| { |
| /** |
| * This is the subordinate <code>InputStream</code> to which method calls |
| * are redirected |
| */ |
| protected InputStream in; |
| |
| /** |
| * Create a <code>FilterInputStream</code> with the specified subordinate |
| * <code>InputStream</code>. |
| * |
| * @param in The subordinate <code>InputStream</code> |
| */ |
| protected FilterInputStream(InputStream in) |
| { |
| this.in = in; |
| } |
| |
| /** |
| * Calls the <code>in.mark(int)</code> method. |
| * |
| * @param readlimit The parameter passed to <code>in.mark(int)</code> |
| */ |
| public void mark(int readlimit) |
| { |
| 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.available()</code> method. |
| * |
| * @return The value returned from <code>in.available()</code> |
| * |
| * @exception IOException If an error occurs |
| */ |
| public int available() throws IOException |
| { |
| return in.available(); |
| } |
| |
| /** |
| * Calls the <code>in.skip(long)</code> method |
| * |
| * @param numBytes The requested number of bytes to skip. |
| * |
| * @return The value returned from <code>in.skip(long)</code> |
| * |
| * @exception IOException If an error occurs |
| */ |
| public long skip(long numBytes) throws IOException |
| { |
| return in.skip(numBytes); |
| } |
| |
| /** |
| * 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>read(byte[], int, int)</code> overloaded method. |
| * Note that |
| * this method does not redirect its call directly to a corresponding |
| * method in <code>in</code>. This allows subclasses to override only the |
| * three argument version of <code>read</code>. |
| * |
| * @param buf The buffer to read bytes into |
| * |
| * @return The value retured from <code>in.read(byte[], int, int)</code> |
| * |
| * @exception IOException If an error occurs |
| */ |
| public int read(byte[] buf) throws IOException |
| { |
| return read(buf, 0, buf.length); |
| } |
| |
| /** |
| * Calls the <code>in.read(byte[], int, int)</code> method. |
| * |
| * @param buf The buffer to read bytes into |
| * @param offset The index into the buffer to start storing bytes |
| * @param len The maximum number of bytes to read. |
| * |
| * @return The value retured from <code>in.read(byte[], int, int)</code> |
| * |
| * @exception IOException If an error occurs |
| */ |
| public int read(byte[] buf, int offset, int len) throws IOException |
| { |
| return in.read(buf, offset, len); |
| } |
| |
| /** |
| * This method closes the input stream by closing the input stream that |
| * this object is filtering. Future attempts to access this stream may |
| * throw an exception. |
| * |
| * @exception IOException If an error occurs |
| */ |
| public void close() throws IOException |
| { |
| in.close(); |
| } |
| } |