test/java/io/BufferedReader/MarkedFillAtEOF.java

/*
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 * 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.
 *
 * 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.
 *
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 */

/* @test
   @bug 4069687
   @summary Test if fill() will behave correctly at EOF
            when mark is set.
*/

import java.io.*;

public class MarkedFillAtEOF {

    public static void main(String[] args) throws Exception {
        BufferedReader r = new BufferedReader(new StringReader("12"));
        int count = 0;

        r.read();
        r.mark(2);
        // trigger the call to fill()
        while (r.read() != -1);
        r.reset();

        // now should only read 1 character
        while (r.read() != -1) {
            count++;
        }
        if (count != 1) {
            throw new Exception("Expect 1 character, but got " + count);
        }
    }
}