/*

 * Copyright 2005 Sun Microsystems, Inc.  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.  Sun designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Sun in the LICENSE file that accompanied this code.

 *

 * 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 */

/*

 * The contents of this file are subject to the Sun Public License

 * Version 1.0 (the "License"); you may not use this file except in

 * compliance with the License. A copy of the License is available at

 * http://www.sun.com/, and in the file LICENSE.html in the

 * doc directory.

 *

 * The Original Code is HAT. The Initial Developer of the

 * Original Code is Bill Foote, with contributions from others

 * at JavaSoft/Sun. Portions created by Bill Foote and others

 * at Javasoft/Sun are Copyright (C) 1997-2004. All Rights Reserved.

 *

 * In addition to the formal license, I ask that you don't

 * change the history or donations files without permission.

 *

 */

package com.sun.tools.hat.internal.parser;

import java.io.FilterInputStream;

import java.io.IOException;

import java.io.InputStream;

/**

 * InputStream that keeps track of total bytes read (in effect

 * 'position' in stream) from the input stream.

 *

 */

public class PositionInputStream extends FilterInputStream {

    private long position = 0L;

    public PositionInputStream(InputStream in) {

        super(in);

    }

    public int read() throws IOException {

        int res = super.read();

        if (res != -1) position++;

        return res;

    }

    public int read(byte[] b, int off, int len) throws IOException {

        int res = super.read(b, off, len);

        if (res != -1) position += res;

        return res;

    }

    public long skip(long n) throws IOException {

        long res = super.skip(n);

        position += res;

        return res;

    }

    public boolean markSupported() {

        return false;

    }

    public void mark(int readLimit) {

        throw new UnsupportedOperationException("mark");

    }

    public void reset() {

        throw new UnsupportedOperationException("reset");

    }

    public long position() {

        return position;

    }

}