/* Copyright (c) 2001-2019, The HSQL Development Group
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 *
 * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 *
 * Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *
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 * contributors may be used to endorse or promote products derived from this
 * software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
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 */


package org.hsqldb.lib;

import java.io.IOException;
import java.io.InputStream;
import java.io.Reader;

This class is an part implementation of DataInput. It wraps a Reader object.
Author:
Fred Toussi (fredt@users dot sourceforge.net)
Version:
1.9.0
Since:
1.9.0/**
 * This class is an part implementation of DataInput. It wraps a Reader object.
 *
 * @author Fred Toussi (fredt@users dot sourceforge.net)
 * @version 1.9.0
 * @since 1.9.0
 */
public class ReaderInputStream extends InputStream {

    protected Reader reader;
    protected long    pos;
    int              lastChar = -1;

    public ReaderInputStream(Reader reader) {
        this.reader = reader;
        this.pos    = 0;
    }

    public int read() throws IOException {

        if (lastChar >= 0) {
            int val = lastChar & 0xff;

            lastChar = -1;

            pos++;
            return val;
        }

        lastChar = reader.read();

        if (lastChar < 0) {
            return lastChar;
        }

        pos++;
        return lastChar >> 8;
    }
}