/*

 * Copyright (c) 1998, 2018, 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 4091859 8189366

 * @summary Test Socket.available()

 * @run main CloseAvailable

 * @run main/othervm -Djava.net.preferIPv4Stack=true CloseAvailable

 */

import java.net.*;

import java.io.*;

public class CloseAvailable {

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

        testClose();

        testEOF(true);

        testEOF(false);

        testIOEOnClosed(true);

        testIOEOnClosed(false);

    }

    static void testClose() throws IOException {

        boolean error = true;

        InetAddress addr = InetAddress.getLocalHost();

        ServerSocket ss = new ServerSocket(0);

        int port = ss.getLocalPort();

        Thread t = new Thread(new Thread("Close-Available-1") {

            public void run() {

                try {

                    Socket s = new Socket(addr, port);

                    s.close();

                } catch (Exception e) {

                    e.printStackTrace();

                }

            }

        });

        t.start();

        Socket  soc = ss.accept();

        ss.close();

        DataInputStream is = new DataInputStream(soc.getInputStream());

        is.close();

        try {

            is.available();

        }

        catch (IOException ex) {

            error = false;

        }

        if (error)

            throw new RuntimeException("Available() can be called after stream closed.");

    }

    // Verifies consistency of `available` behaviour when EOF reached, both

    // explicitly and implicitly.

    static void testEOF(boolean readUntilEOF) throws IOException {

        System.out.println("testEOF, readUntilEOF: " + readUntilEOF);

        InetAddress addr = InetAddress.getLoopbackAddress();

        ServerSocket ss = new ServerSocket();

        ss.bind(new InetSocketAddress(addr, 0), 0);

        int port = ss.getLocalPort();

        try (Socket s = new Socket(addr, port)) {

            s.getOutputStream().write(0x42);

            s.shutdownOutput();

            try (Socket soc = ss.accept()) {

                ss.close();

                InputStream is = soc.getInputStream();

                int b = is.read();

                assert b == 0x42;

                assert !s.isClosed();

                if (readUntilEOF) {

                    b = is.read();

                    assert b == -1;

                }

                int a;

                for (int i = 0; i < 100; i++) {

                    a = is.available();

                    System.out.print(a + ", ");

                    if (a != 0)

                        throw new RuntimeException("Unexpected non-zero available: " + a);

                }

                assert !s.isClosed();

                assert is.read() == -1;

            }

        }

        System.out.println("\ncomplete");

    }

    // Verifies IOException thrown by `available`, on a closed input stream

    // that may, or may not, have reached EOF prior to closure.

    static void testIOEOnClosed(boolean readUntilEOF) throws IOException {

        System.out.println("testIOEOnClosed, readUntilEOF: " + readUntilEOF);

        InetAddress addr = InetAddress.getLoopbackAddress();

        ServerSocket ss = new ServerSocket();

        ss.bind(new InetSocketAddress(addr, 0), 0);

        int port = ss.getLocalPort();

        try (Socket s = new Socket(addr, port)) {

            s.getOutputStream().write(0x43);

            s.shutdownOutput();

            try (Socket soc = ss.accept()) {

                ss.close();

                InputStream is = soc.getInputStream();

                int b = is.read();

                assert b == 0x43;

                assert !s.isClosed();

                if (readUntilEOF) {

                    b = is.read();

                    assert b == -1;

                }

                is.close();

                try {

                    b = is.available();

                    throw new RuntimeException("UNEXPECTED successful read: " + b);

                } catch (IOException expected) {

                    System.out.println("caught expected IOException:" + expected);

                }

            }

        }

        System.out.println("\ncomplete");

    }

}