/*

 * Copyright (c) 2001, 2017, 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 4417152 4481572 6248930 6725399 6884800

 * @summary Test Channels basic functionality

 */

import java.io.*;

import java.nio.*;

import java.nio.charset.*;

import java.nio.channels.*;

public class Basic {

    static String message;

    static String encoding;

    static File blah;

    static int ITERATIONS = 500;

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

        message = "ascii data for a test";

        encoding = "ISO-8859-1";

        test();

        message = "\ucafe\ubabe\ucafe\ubabe\ucafe\ubabe";

        encoding = "UTF-8";

        test();

    }

    static void failNpeExpected() {

        throw new RuntimeException("Did not get the expected NullPointerException.");

    }

    private static void test() throws Exception {

        //Test if methods of Channels throw NPE with null argument(s)

        try {

            Channels.newInputStream((ReadableByteChannel)null);

            failNpeExpected();

        } catch (NullPointerException npe) {}

        try {

            Channels.newOutputStream((WritableByteChannel)null);

            failNpeExpected();

        } catch (NullPointerException npe) {}

        try {

            ReadableByteChannel channel = Channels.newChannel((InputStream)null);

            failNpeExpected();

        } catch (NullPointerException ne) {}  // OK. As expected.

        try {

            WritableByteChannel channel = Channels.newChannel((OutputStream)null);

            failNpeExpected();

        } catch (NullPointerException ne) {}  // OK. As expected.

        WritableByteChannel wbc = new WritableByteChannel() {

            public int write(ByteBuffer src) { return 0; }

            public void close() throws IOException { }

            public boolean isOpen() { return true; }

        };

        ReadableByteChannel rbc = new ReadableByteChannel() {

            public int read(ByteBuffer dst) { return 0; }

            public void close() {}

            public boolean isOpen() { return true; }

        };

        try {

            Channels.newReader((ReadableByteChannel)null,

                               Charset.defaultCharset().newDecoder(),

                               -1);

            failNpeExpected();

        } catch (NullPointerException npe) {}

        try {

            Channels.newReader(rbc, (CharsetDecoder)null, -1);

            failNpeExpected();

        } catch (NullPointerException npe) {}

        try {

            Channels.newReader((ReadableByteChannel)null,

                               Charset.defaultCharset().name());

            failNpeExpected();

        } catch (NullPointerException npe) {}

        try {

            Channels.newReader(rbc, (String)null);

            failNpeExpected();

        } catch (NullPointerException npe) {}

        try {

            Channels.newReader(null, (String)null);

            failNpeExpected();

        } catch (NullPointerException npe) {}

        try {

            Channels.newReader(rbc, (Charset)null);

            failNpeExpected();

        } catch (NullPointerException npe) {}

        try {

            Channels.newReader(null, (Charset)null);

            failNpeExpected();

        } catch (NullPointerException npe) {}

        try {

            Channels.newWriter((WritableByteChannel)null,

                               Charset.defaultCharset().newEncoder(),

                               -1);

            failNpeExpected();

        } catch (NullPointerException npe) {}

        try {

            Channels.newWriter(null, null, -1);

            failNpeExpected();

        } catch (NullPointerException npe) {}

        try {

            Channels.newWriter(wbc, null, -1);

            failNpeExpected();

        } catch (NullPointerException npe) {}

        try {

            Channels.newWriter((WritableByteChannel)null,

                               Charset.defaultCharset().name());

            failNpeExpected();

        } catch (NullPointerException npe) {}

        try {

            Channels.newWriter(wbc, (String)null);

            failNpeExpected();

        } catch (NullPointerException npe) {}

        try {

            Channels.newWriter(null, (String)null);

            failNpeExpected();

        } catch (NullPointerException npe) {}

        try {

            Channels.newWriter(wbc, (Charset)null);

            failNpeExpected();

        } catch (NullPointerException npe) {}

        try {

            Channels.newWriter(null, (Charset)null);

            failNpeExpected();

        } catch (NullPointerException npe) {}

        try {

            blah = File.createTempFile("blah", null);

            testNewOutputStream(blah);

            readAndCheck(blah);

            blah.delete();

            writeOut(blah, ITERATIONS);

            testNewInputStream(blah);

            blah.delete();

            testNewChannelOut(blah);

            readAndCheck(blah);

            blah.delete();

            testNewChannelWriteAfterClose(blah);

            testNewChannelReadAfterClose(blah);

            blah.delete();

            writeOut(blah, ITERATIONS);

            testNewChannelIn(blah);

            test4481572(blah);

            blah.delete();

            testNewWriter(blah);

            readAndCheck(blah);

            blah.delete();

            writeOut(blah, ITERATIONS);

            testNewReader(blah);

        } finally {

            blah.delete();

        }

    }

    private static void readAndCheck(File blah) throws Exception {

        FileInputStream fis = new FileInputStream(blah);

        int messageSize = message.length() * ITERATIONS * 3 + 1;

        byte bb[] = new byte[messageSize];

        int bytesRead = 0;

        int totalRead = 0;

        while (bytesRead != -1) {

            totalRead += bytesRead;

            bytesRead = fis.read(bb, totalRead, messageSize - totalRead);

        }

        String result = new String(bb, 0, totalRead, encoding);

        int len = message.length();

        for (int i=0; i<ITERATIONS; i++) {

            String segment = result.substring(i++ * len, i * len);

            if (!segment.equals(message))

                throw new RuntimeException("Test failed");

        }

        fis.close();

    }

    private static void writeOut(File blah, int limit) throws Exception {

        FileOutputStream fos = new FileOutputStream(blah);

        for (int i=0; i<limit; i++)

            fos.write(message.getBytes(encoding));

        fos.close();

    }

    private static void testNewOutputStream(File blah) throws Exception {

        FileOutputStream fos = new FileOutputStream(blah);

        FileChannel fc = fos.getChannel();

        WritableByteChannel wbc = (WritableByteChannel)fc;

        OutputStream os = Channels.newOutputStream(wbc);

        for (int i=0; i<ITERATIONS; i++)

            os.write(message.getBytes(encoding));

        os.close();

        fos.close();

    }

    private static void testNewInputStream(File blah) throws Exception {

        FileInputStream fis = new FileInputStream(blah);

        FileChannel fc = fis.getChannel();

        InputStream is = Channels.newInputStream(fc);

        int messageSize = message.length() * ITERATIONS * 3 + 1;

        byte bb[] = new byte[messageSize];

        int bytesRead = 0;

        int totalRead = 0;

        while (bytesRead != -1) {

            totalRead += bytesRead;

            long rem = Math.min(fc.size() - totalRead, (long)Integer.MAX_VALUE);

            if (is.available() != (int)rem)

                throw new RuntimeException("available not useful or not maximally useful");

            bytesRead = is.read(bb, totalRead, messageSize - totalRead);

        }

        if (is.available() != 0)

           throw new RuntimeException("available() should return 0 at EOF");

        String result = new String(bb, 0, totalRead, encoding);

        int len = message.length();

        for (int i=0; i<ITERATIONS; i++) {

            String segment = result.substring(i++ * len, i * len);

            if (!segment.equals(message))

                throw new RuntimeException("Test failed");

        }

        is.close();

        fis.close();

    }

    private static void testNewChannelOut(File blah) throws Exception {

        ExtendedFileOutputStream fos = new ExtendedFileOutputStream(blah);

        WritableByteChannel wbc = Channels.newChannel(fos);

        for (int i=0; i<ITERATIONS; i++)

            wbc.write(ByteBuffer.wrap(message.getBytes(encoding)));

        wbc.close();

        fos.close();

    }

    private static void testNewChannelIn(File blah) throws Exception {

        ExtendedFileInputStream fis = new ExtendedFileInputStream(blah);

        ReadableByteChannel rbc = Channels.newChannel(fis);

        int messageSize = message.length() * ITERATIONS * 3;

        byte data[] = new byte[messageSize+1];

        ByteBuffer bb = ByteBuffer.wrap(data);

        int bytesRead = 0;

        int totalRead = 0;

        while (bytesRead != -1) {

            totalRead += bytesRead;

            bytesRead = rbc.read(bb);

        }

        String result = new String(data, 0, totalRead, encoding);

        int len = message.length();

        for (int i=0; i<ITERATIONS; i++) {

            String segment = result.substring(i++ * len, i * len);

            if (!segment.equals(message))

                throw new RuntimeException("Test failed");

        }

        rbc.close();

        fis.close();

    }

    private static void testNewChannelWriteAfterClose(File blah)

        throws Exception {

        try (ExtendedFileOutputStream fos =

            new ExtendedFileOutputStream(blah)) {

            WritableByteChannel wbc = Channels.newChannel(fos);

            wbc.close();

            try {

                wbc.write(ByteBuffer.allocate(0));

                throw new RuntimeException

                    ("No ClosedChannelException on WritableByteChannel::write");

            } catch (ClosedChannelException expected) {

            }

        }

    }

    private static void testNewChannelReadAfterClose(File blah)

        throws Exception {

        try (ExtendedFileInputStream fis = new ExtendedFileInputStream(blah)) {

            ReadableByteChannel rbc = Channels.newChannel(fis);

            rbc.close();

            try {

                rbc.read(ByteBuffer.allocate(0));

                throw new RuntimeException

                    ("No ClosedChannelException on ReadableByteChannel::read");

            } catch (ClosedChannelException expected) {

            }

        }

    }

    // Causes BufferOverflowException if bug 4481572 is present.

    private static void test4481572(File blah) throws Exception {

        ExtendedFileInputStream fis = new ExtendedFileInputStream(blah);

        ReadableByteChannel rbc = Channels.newChannel(fis);

        byte data[] = new byte[9000];

        ByteBuffer bb = ByteBuffer.wrap(data);

        int bytesRead = 1;

        int totalRead = 0;

        while (bytesRead > 0) {

            totalRead += bytesRead;

            bytesRead = rbc.read(bb);

        }

        rbc.close();

        fis.close();

    }

    private static void testNewWriter(File blah) throws Exception {

        FileOutputStream fos = new FileOutputStream(blah);

        WritableByteChannel wbc = (WritableByteChannel)fos.getChannel();

        Writer w = Channels.newWriter(wbc, encoding);

        char data[] = new char[40];

        message.getChars(0, message.length(), data, 0);

        for (int i=0; i<ITERATIONS; i++)

            w.write(data, 0, message.length());

        w.flush();

        w.close();

        fos.close();

    }

    private static void testNewReader(File blah) throws Exception {

        FileInputStream fis = new FileInputStream(blah);

        ReadableByteChannel rbc = (ReadableByteChannel)fis.getChannel();

        Reader r = Channels.newReader(rbc, encoding);

        int messageSize = message.length() * ITERATIONS;

        char data[] = new char[messageSize];

        int totalRead = 0;

        int charsRead = 0;

        while (totalRead < messageSize) {

            totalRead += charsRead;

            charsRead = r.read(data, totalRead, messageSize - totalRead);

        }

        String result = new String(data, 0, totalRead);

        int len = message.length();

        for (int i=0; i<ITERATIONS; i++) {

            String segment = result.substring(i++ * len, i * len);

            if (!segment.equals(message))

                throw new RuntimeException("Test failed");

        }

        r.close();

        fis.close();

    }

}

class ExtendedFileInputStream extends java.io.FileInputStream {

    ExtendedFileInputStream(File file) throws FileNotFoundException {

        super(file);

    }

}

class ExtendedFileOutputStream extends java.io.FileOutputStream {

    ExtendedFileOutputStream(File file) throws FileNotFoundException {

        super(file);

    }

}