test/jdk/java/io/Reader/ReadIntoZeroLengthArray.java

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * 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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import java.io.CharArrayReader;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.io.LineNumberReader;
import java.io.PushbackReader;
import java.io.Reader;
import java.io.StringReader;
import org.testng.Assert;
import org.testng.annotations.AfterTest;
import org.testng.annotations.BeforeTest;
import org.testng.annotations.DataProvider;
import org.testng.annotations.Test;

/*
 * @test
 * @bug 8248383
 * @summary Ensure that zero is returned for read into zero length array
 * @run testng ReadIntoZeroLengthArray
 */
public class ReadIntoZeroLengthArray {
    private File file;

    private char[] cbuf0;
    private char[] cbuf1;

    @BeforeTest
    public void setup() throws IOException {
        file = File.createTempFile("foo", "bar", new File("."));
        cbuf0 = new char[0];
        cbuf1 = new char[1];
    }

    @AfterTest
    public void teardown() throws IOException {
        file.delete();
    }

    @DataProvider(name = "readers")
    public Object[][] getReaders() throws IOException {
        Reader fileReader = new FileReader(file);
        return new Object[][] {
            {new LineNumberReader(fileReader)},
            {new CharArrayReader(new char[] {27})},
            {new PushbackReader(fileReader)},
            {fileReader},
            {new StringReader(new String(new byte[] {(byte)42}))}
        };
    }

    @Test(dataProvider = "readers")
    void test0(Reader r) throws IOException {
        Assert.assertEquals(r.read(cbuf0), 0);
    }

    @Test(dataProvider = "readers")
    void test1(Reader r) throws IOException {
        Assert.assertEquals(r.read(cbuf1, 0, 0), 0);
    }
}