1/*
2 * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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5 * This code is free software; you can redistribute it and/or modify it
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7 * published by the Free Software Foundation.
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10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
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22 */
23
24/* @test
25 * @bug 4639943
26 * @summary  Checks that Windows behavior matches Solaris for
27 *           various read/select combinations.
28 * @author kladko
29 */
30
31import java.nio.ByteBuffer;
32import java.nio.channels.Selector;
33import java.nio.channels.SelectionKey;
34import java.nio.channels.SocketChannel;
35
36public class SelectAfterRead {
37
38    private static final int TIMEOUT = 1000;
39
40    public static void main(String[] argv) throws Exception {
41
42        // server: accept connection and write one byte
43        try (ByteServer server = new ByteServer();
44             SocketChannel sc = SocketChannel.open(server.address())) {
45
46            server.acceptConnection();
47            server.write(1);
48
49            try (Selector sel = Selector.open()) {
50                sc.read(ByteBuffer.allocate(1));
51                sc.configureBlocking(false);
52                sc.register(sel, SelectionKey.OP_READ);
53                // previously on Windows select would select channel here, although there was
54                // nothing to read
55                if (sel.selectNow() != 0)
56                    throw new Exception("Select returned nonzero value");
57            }
58        }
59
60        // Now we will test a two reads combination
61        // server: accept connection and write two bytes
62        try (ByteServer server = new ByteServer();
63             SocketChannel sc = SocketChannel.open(server.address())) {
64
65            server.acceptConnection();
66            server.write(2);
67
68            try (Selector sel = Selector.open()) {
69                sc.configureBlocking(false);
70                sc.register(sel, SelectionKey.OP_READ);
71                if (sel.select(TIMEOUT) != 1)
72                    throw new Exception("One selected key expected");
73                sel.selectedKeys().clear();
74                // previously on Windows a channel would get selected only once
75                if (sel.selectNow() != 1)
76                    throw new Exception("One selected key expected");
77                // Previously on Windows two consequent reads would cause select()
78                // to select a channel, although there was nothing remaining to
79                // read in the channel
80                if (sc.read(ByteBuffer.allocate(1)) != 1)
81                    throw new Exception("One byte expected");
82                if (sc.read(ByteBuffer.allocate(1)) != 1)
83                    throw new Exception("One byte expected");
84                if (sel.selectNow() != 0)
85                    throw new Exception("Select returned nonzero value");
86            }
87        }
88    }
89}
90