Java example source code file (OpsAfterClose.java)

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Java - Java tags/keywords

bufferedreader, chararrayreader, exception, filereader, inputstreamreader, ioexception, linenumberreader, opsafterclose, pipedreader, pipedwriter, pushbackreader, read_buf, ready, stringreader

The OpsAfterClose.java Java example source code

/*
 * Copyright (c) 2005, Oracle and/or its affiliates. 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.
 *
 * 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

/**
 *  @test
 *  @bug 5085148 4143651
 *  @summary Test if Reader methods will check if the stream
 *          has been closed.
 */

import java.io.*;

public enum OpsAfterClose {

        READ { boolean check(Reader r) {
                    try {
                        r.read();
                    } catch (IOException io) {
                        return true;
                    }
                    return false;
             } },

        READ_BUF { boolean check(Reader r) {
                    try {
                        char buf[] = new char[2];
                        int len = 1;
                        r.read(buf, 0, len);
                    } catch (IOException io) {
                        return true;
                    }
                    return false;
             } },
        READY { boolean check(Reader r) {
                    try {
                         r.ready();
                    } catch (IOException io) {
                        return true;
                    }
                    return false;
             } },
        MARK { boolean check(Reader r) {
                   try {
                         r.mark(1);
                    } catch (IOException io) {
                        return true;
                    }
                    return false;
             } },
        SKIP { boolean check(Reader r) {
                   try {
                         r.skip(1);
                    } catch (IOException io) {
                        return true;
                    }
                    return false;
             } },
        RESET { boolean check(Reader r) {
                   try {
                         r.reset();
                    } catch (IOException io) {
                        return true;
                    }
                    return false;
             } },
        CLOSE { boolean check(Reader r) {
                   try {
                         r.close();
                    } catch (IOException io) {
                        return false;
                    }
                    return true;
             } };

    abstract boolean check(Reader r);

    public static void main(String args[]) throws Exception {

        boolean failed = false;

        BufferedReader br = new BufferedReader(
                            new StringReader("abc def ghi"));
        if (testReader(br)) {
            failed = true;
        }

        CharArrayReader car = new CharArrayReader(new char[2]);
        if (testReader(car)) {
            failed = true;
        }

        PushbackReader pbr = new PushbackReader(
                                new CharArrayReader(new char[2]));
        if (testReader(pbr)) {
            failed = true;
        }
        if (testPushbackReader(pbr)) {
            failed = true;
        }

        StringReader sr = new StringReader("abc def ghi");
        if (testReader(sr)) {
            failed = true;
        }

        InputStreamReader isr = new InputStreamReader(
                                new ByteArrayInputStream("abc".getBytes()));
        if (testReader(isr)) {
            failed = true;
        }

        LineNumberReader lnr = new LineNumberReader(
                            new StringReader("abc def ghi"));
        if (testReader(lnr)) {
            failed = true;
        }

        File f = new File(System.getProperty("test.dir", "."),
                          "NewFile");
        f.createNewFile();
        f.deleteOnExit();

        FileReader fr = new FileReader(f);
        if (testReader(fr)) {
            failed = true;
        }

        PipedWriter pw = new PipedWriter();
        PipedReader pr = new PipedReader(pw);
        if (testReader(pr)) {
            failed = true;
        }
        if (failed) {
            throw new Exception("Test failed for some of the operation{s}" +
                " on some of the reader{s}, check the messages");
        }
    }

    private static boolean testReader(Reader r) throws Exception {
        r.close();
        boolean failed = false;
        boolean result;
        System.out.println("Testing reader:" + r);
        for (OpsAfterClose op : OpsAfterClose.values()) {
            result = op.check(r);
            if (!result) {
                failed = true;
            }
           System.out.println(op + ":" + result);
        }
        if (failed) {
            System.out.println("Test failed for the failed operation{s}" +
                        " above for the Reader:" + r);
        }
        return failed;
    }

    private static boolean testPushbackReader(PushbackReader pr)
                throws Exception {
        boolean failed = false;
        try {
            pr.unread(1);
            System.out.println("Test failed for unread(int):" + pr);
            failed = true;
        } catch (IOException io) {
           System.out.println("UNREAD(int):true");
        }

        char buf[] = new char[2];
        try {
            pr.unread(buf, 0, 2);
            System.out.println("Test failed for unread(buf, offset, len):" +
                                pr);
            failed = true;
        } catch (IOException io) {
           System.out.println("UNREAD(buf, offset, len):true");
        }
        try {
            pr.unread(buf);
            System.out.println("Test failed for unread(char[] buf):" + pr);
            failed = true;
        } catch (IOException io) {
           System.out.println("UNREAD(buf):true");
        }
        return failed;
    }
}