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. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 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). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 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