Mercurial > hg > release > icedtea-1.9
view overlays/nio2/openjdk/jdk/test/java/nio/channels/AsynchronousFileChannel/Lock.java @ 1719:ab30fa9f3e55
Move NIO2 tests to right directory.
2009-03-06 Andrew John Hughes <ahughes@redhat.com>
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/io/Inputs/Basic.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/channels/AsynchronousChannelGroup/AsExecutor.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/channels/AsynchronousChannelGroup/Attack.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/channels/AsynchronousChannelGroup/Basic.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/channels/AsynchronousChannelGroup/GroupOfOne.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/channels/AsynchronousChannelGroup/Identity.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/channels/AsynchronousChannelGroup/PrivilegedThreadFactory.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/channels/AsynchronousChannelGroup/Restart.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/channels/AsynchronousChannelGroup/Unbounded.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/channels/AsynchronousChannelGroup/run_any_task.sh,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/channels/AsynchronousDatagramChannel/Basic.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/channels/AsynchronousFileChannel/Basic.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/channels/AsynchronousFileChannel/CustomThreadPool.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/channels/AsynchronousFileChannel/Lock.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/channels/AsynchronousFileChannel/MyThreadFactory.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/channels/AsynchronousServerSocketChannel/Basic.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/channels/AsynchronousServerSocketChannel/WithSecurityManager.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/channels/AsynchronousServerSocketChannel/java.policy.allow,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/channels/AsynchronousServerSocketChannel/java.policy.deny,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/channels/AsynchronousSocketChannel/Basic.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/channels/AsynchronousSocketChannel/Leaky.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/channels/Channels/Basic2.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/channels/spi/AsynchronousChannelProvider/CheckProvider.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/channels/spi/AsynchronousChannelProvider/META-INF/services/java.nio.channels.spi.AsynchronousChannelProvider,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/channels/spi/AsynchronousChannelProvider/Provider1.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/channels/spi/AsynchronousChannelProvider/Provider2.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/channels/spi/AsynchronousChannelProvider/custom_provider.sh,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/DirectoryStream/Basic.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/DirectoryStream/Filters.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/DirectoryStream/SecureDS.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/FileStore/Basic.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/FileSystem/Basic.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/Files/ContentType.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/Files/CreateFileTree.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/Files/ForceLoad.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/Files/META-INF/services/java.nio.file.spi.FileTypeDetector,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/Files/Misc.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/Files/PrintFileTree.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/Files/SimpleFileTypeDetector.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/Files/SkipSiblings.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/Files/TerminateWalk.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/Files/content_type.sh,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/Files/walk_file_tree.sh,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/Path/CopyAndMove.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/Path/DeleteOnClose.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/Path/InterruptCopy.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/Path/Links.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/Path/Misc.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/Path/PathOps.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/Path/SBC.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/Path/TemporaryFiles.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/Path/UriImportExport.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/Path/delete_on_close.sh,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/Path/temporary_files.sh,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/PathMatcher/Basic.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/TestUtil.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/WatchService/Basic.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/WatchService/FileTreeModifier.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/WatchService/WithSecurityManager.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/WatchService/denyAll.policy,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/WatchService/grantDirAndOneLevel.policy,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/WatchService/grantDirAndTree.policy,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/WatchService/grantDirOnly.policy,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/attribute/AclFileAttributeView/Basic.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/attribute/Attributes/Basic.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/attribute/BasicFileAttributeView/Basic.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/attribute/DosFileAttributeView/Basic.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/attribute/FileStoreAttributeView/Basic.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/attribute/NamedAttributeView/Basic.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/attribute/PosixFileAttributeView/Basic.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/spi/SetDefaultProvider.java,
* overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/file/spi/TestProvider.java: Moved to...
* overlays/nio2/openjdk/jdk/test/java/io/Inputs/Basic.java,
* overlays/nio2/openjdk/jdk/test/java/nio/channels/AsynchronousChannelGroup/AsExecutor.java,
* overlays/nio2/openjdk/jdk/test/java/nio/channels/AsynchronousChannelGroup/Attack.java,
* overlays/nio2/openjdk/jdk/test/java/nio/channels/AsynchronousChannelGroup/Basic.java,
* overlays/nio2/openjdk/jdk/test/java/nio/channels/AsynchronousChannelGroup/GroupOfOne.java,
* overlays/nio2/openjdk/jdk/test/java/nio/channels/AsynchronousChannelGroup/Identity.java,
* overlays/nio2/openjdk/jdk/test/java/nio/channels/AsynchronousChannelGroup/PrivilegedThreadFactory.java,
* overlays/nio2/openjdk/jdk/test/java/nio/channels/AsynchronousChannelGroup/Restart.java,
* overlays/nio2/openjdk/jdk/test/java/nio/channels/AsynchronousChannelGroup/Unbounded.java,
* overlays/nio2/openjdk/jdk/test/java/nio/channels/AsynchronousChannelGroup/run_any_task.sh,
* overlays/nio2/openjdk/jdk/test/java/nio/channels/AsynchronousDatagramChannel/Basic.java,
* overlays/nio2/openjdk/jdk/test/java/nio/channels/AsynchronousFileChannel/Basic.java,
* overlays/nio2/openjdk/jdk/test/java/nio/channels/AsynchronousFileChannel/CustomThreadPool.java,
* overlays/nio2/openjdk/jdk/test/java/nio/channels/AsynchronousFileChannel/Lock.java,
* overlays/nio2/openjdk/jdk/test/java/nio/channels/AsynchronousFileChannel/MyThreadFactory.java,
* overlays/nio2/openjdk/jdk/test/java/nio/channels/AsynchronousServerSocketChannel/Basic.java,
* overlays/nio2/openjdk/jdk/test/java/nio/channels/AsynchronousServerSocketChannel/WithSecurityManager.java,
* overlays/nio2/openjdk/jdk/test/java/nio/channels/AsynchronousServerSocketChannel/java.policy.allow,
* overlays/nio2/openjdk/jdk/test/java/nio/channels/AsynchronousServerSocketChannel/java.policy.deny,
* overlays/nio2/openjdk/jdk/test/java/nio/channels/AsynchronousSocketChannel/Basic.java,
* overlays/nio2/openjdk/jdk/test/java/nio/channels/AsynchronousSocketChannel/Leaky.java,
* overlays/nio2/openjdk/jdk/test/java/nio/channels/Channels/Basic2.java,
* overlays/nio2/openjdk/jdk/test/java/nio/channels/spi/AsynchronousChannelProvider/CheckProvider.java,
* overlays/nio2/openjdk/jdk/test/java/nio/channels/spi/AsynchronousChannelProvider/META-INF/services/java.nio.channels.spi.AsynchronousChannelProvider,
* overlays/nio2/openjdk/jdk/test/java/nio/channels/spi/AsynchronousChannelProvider/Provider1.java,
* overlays/nio2/openjdk/jdk/test/java/nio/channels/spi/AsynchronousChannelProvider/Provider2.java,
* overlays/nio2/openjdk/jdk/test/java/nio/channels/spi/AsynchronousChannelProvider/custom_provider.sh,
* overlays/nio2/openjdk/jdk/test/java/nio/file/DirectoryStream/Basic.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/DirectoryStream/Filters.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/DirectoryStream/SecureDS.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/FileStore/Basic.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/FileSystem/Basic.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/Files/ContentType.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/Files/CreateFileTree.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/Files/ForceLoad.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/Files/META-INF/services/java.nio.file.spi.FileTypeDetector,
* overlays/nio2/openjdk/jdk/test/java/nio/file/Files/Misc.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/Files/PrintFileTree.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/Files/SimpleFileTypeDetector.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/Files/SkipSiblings.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/Files/TerminateWalk.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/Files/content_type.sh,
* overlays/nio2/openjdk/jdk/test/java/nio/file/Files/walk_file_tree.sh,
* overlays/nio2/openjdk/jdk/test/java/nio/file/Path/CopyAndMove.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/Path/DeleteOnClose.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/Path/InterruptCopy.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/Path/Links.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/Path/Misc.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/Path/PathOps.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/Path/SBC.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/Path/TemporaryFiles.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/Path/UriImportExport.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/Path/delete_on_close.sh,
* overlays/nio2/openjdk/jdk/test/java/nio/file/Path/temporary_files.sh,
* overlays/nio2/openjdk/jdk/test/java/nio/file/PathMatcher/Basic.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/TestUtil.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/WatchService/Basic.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/WatchService/FileTreeModifier.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/WatchService/WithSecurityManager.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/WatchService/denyAll.policy,
* overlays/nio2/openjdk/jdk/test/java/nio/file/WatchService/grantDirAndOneLevel.policy,
* overlays/nio2/openjdk/jdk/test/java/nio/file/WatchService/grantDirAndTree.policy,
* overlays/nio2/openjdk/jdk/test/java/nio/file/WatchService/grantDirOnly.policy,
* overlays/nio2/openjdk/jdk/test/java/nio/file/attribute/AclFileAttributeView/Basic.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/attribute/Attributes/Basic.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/attribute/BasicFileAttributeView/Basic.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/attribute/DosFileAttributeView/Basic.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/attribute/FileStoreAttributeView/Basic.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/attribute/NamedAttributeView/Basic.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/attribute/PosixFileAttributeView/Basic.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/spi/SetDefaultProvider.java,
* overlays/nio2/openjdk/jdk/test/java/nio/file/spi/TestProvider.java: here.
author | Andrew John Hughes <ahughes@redhat.com> |
---|---|
date | Fri, 06 Mar 2009 12:26:40 +0000 |
parents | overlays/nio2/openjdk/jdk/test/org/classpath/icedtea/java/nio/channels/AsynchronousFileChannel/Lock.java@2257885742d0 |
children |
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/* * Copyright 2007-2008 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, * CA 95054 USA or visit www.sun.com if you need additional information or * have any questions. */ /* @test * @bug 4607272 * @summary Unit test for AsynchronousFileChannel#lock method */ import java.net.*; import java.nio.ByteBuffer; import java.nio.charset.Charset; import java.nio.file.*; import static java.nio.file.StandardOpenOption.*; import java.nio.channels.*; import java.io.File; import java.io.IOException; import java.io.InputStream; import java.util.Random; import java.util.concurrent.*; public class Lock { static final Random rand = new Random(); public static void main(String[] args) throws Exception { if (args.length > 0 && args[0].equals("-lockslave")) { int port = Integer.parseInt(args[1]); runLockSlave(port); System.exit(0); } LockSlaveMirror slave = startLockSlave(); try { // create temporary file File blah = File.createTempFile("blah", null); blah.deleteOnExit(); testLockProtocol(blah, slave); testAsyncClose(blah, slave); } finally { slave.shutdown(); } } // test locking protocol static void testLockProtocol(File file, LockSlaveMirror slave) throws Exception { FileLock fl; // slave VM opens file and acquires exclusive lock slave.open(file.getPath()).lock(); AsynchronousFileChannel ch = AsynchronousFileChannel .open(file.toPath(), READ, WRITE); // this VM tries to acquire lock // (lock should not be acquire until released by slave VM) Future<FileLock> result = ch.lock(); try { result.get(2, TimeUnit.SECONDS); throw new RuntimeException("Timeout expected"); } catch (TimeoutException x) { } // slave VM releases lock slave.unlock(); // this VM should now acquire lock fl = result.get(); fl.release(); // slave VM acquires lock on range slave.lock(0, 10, false); // this VM acquires lock on non-overlapping range fl = ch.lock(10, 10, false, null, null).get(); fl.release(); // done ch.close(); slave.close(); } // test close of channel with outstanding lock operation static void testAsyncClose(File file, LockSlaveMirror slave) throws Exception { // slave VM opens file and acquires exclusive lock slave.open(file.getPath()).lock(); for (int i=0; i<100; i++) { AsynchronousFileChannel ch = AsynchronousFileChannel .open(file.toPath(), READ, WRITE); // try to lock file (should not complete because file is locked by slave) Future<FileLock> result = ch.lock(); try { result.get(rand.nextInt(100), TimeUnit.MILLISECONDS); throw new RuntimeException("Timeout expected"); } catch (TimeoutException x) { } // close channel with lock operation outstanding ch.close(); // operation should complete with AsynchronousCloseException try { result.get(); throw new RuntimeException("ExecutionException expected"); } catch (ExecutionException x) { if (!(x.getCause() instanceof AsynchronousCloseException)) { x.getCause().printStackTrace(); throw new RuntimeException("AsynchronousCloseException expected"); } } } slave.close(); } // starts a "lock slave" in another process, returning a mirror object to // control the slave static LockSlaveMirror startLockSlave() throws Exception { ServerSocketChannel ssc = ServerSocketChannel.open() .bind(new InetSocketAddress(0)); int port = ((InetSocketAddress)(ssc.getLocalAddress())).getPort(); String sep = FileSystems.getDefault().getSeparator(); String command = System.getProperty("java.home") + sep + "bin" + sep + "java Lock -lockslave " + port; Process p = Runtime.getRuntime().exec(command); IOHandler.handle(p.getInputStream()); IOHandler.handle(p.getErrorStream()); // wait for slave to connect SocketChannel sc = ssc.accept(); return new LockSlaveMirror(sc); } // commands that the slave understands static final String OPEN_CMD = "open"; static final String CLOSE_CMD = "close"; static final String LOCK_CMD = "lock"; static final String UNLOCK_CMD = "unlock"; static final char TERMINATOR = ';'; // provides a proxy to a "lock slave" static class LockSlaveMirror { private final SocketChannel sc; LockSlaveMirror(SocketChannel sc) { this.sc = sc; } private void sendCommand(String cmd, String... params) throws IOException { for (String s: params) { cmd += " " + s; } cmd += TERMINATOR; ByteBuffer buf = Charset.defaultCharset().encode(cmd); while (buf.hasRemaining()) { sc.write(buf); } // wait for ack buf = ByteBuffer.allocate(1); int n = sc.read(buf); if (n != 1) throw new RuntimeException("Reply expected"); if (buf.get(0) != TERMINATOR) throw new RuntimeException("Terminated expected"); } LockSlaveMirror open(String file) throws IOException { sendCommand(OPEN_CMD, file); return this; } void close() throws IOException { sendCommand(CLOSE_CMD); } LockSlaveMirror lock() throws IOException { sendCommand(LOCK_CMD); return this; } LockSlaveMirror lock(long position, long size, boolean shared) throws IOException { sendCommand(LOCK_CMD, position + "," + size + "," + shared); return this; } LockSlaveMirror unlock() throws IOException { sendCommand(UNLOCK_CMD); return this; } void shutdown() throws IOException { sc.close(); } } // Helper class to direct process output to the parent System.out static class IOHandler implements Runnable { private final InputStream in; IOHandler(InputStream in) { this.in = in; } static void handle(InputStream in) { IOHandler handler = new IOHandler(in); Thread thr = new Thread(handler); thr.setDaemon(true); thr.start(); } public void run() { try { byte b[] = new byte[100]; for (;;) { int n = in.read(b); if (n < 0) return; for (int i=0; i<n; i++) { System.out.print((char)b[i]); } } } catch (IOException ioe) { } } } // slave process that responds to simple commands a socket connection static void runLockSlave(int port) throws Exception { // establish connection to parent SocketChannel sc = SocketChannel.open(new InetSocketAddress(port)); ByteBuffer buf = ByteBuffer.allocateDirect(1024); FileChannel fc = null; FileLock fl = null; try { for (;;) { // read command (ends with ";") buf.clear(); int n, last = 0; do { n = sc.read(buf); if (n < 0) return; if (n == 0) throw new AssertionError(); last += n; } while (buf.get(last-1) != TERMINATOR); // decode into command and optional parameter buf.flip(); String s = Charset.defaultCharset().decode(buf).toString(); int sp = s.indexOf(" "); String cmd = (sp < 0) ? s.substring(0, s.length()-1) : s.substring(0, sp); String param = (sp < 0) ? "" : s.substring(sp+1, s.length()-1); // execute if (cmd.equals(OPEN_CMD)) { if (fc != null) throw new RuntimeException("File already open"); fc = FileChannel.open(Paths.get(param),READ, WRITE); } if (cmd.equals(CLOSE_CMD)) { if (fc == null) throw new RuntimeException("No file open"); fc.close(); fc = null; fl = null; } if (cmd.equals(LOCK_CMD)) { if (fl != null) throw new RuntimeException("Already holding lock"); if (param.length() == 0) { fl = fc.lock(); } else { String[] values = param.split(","); if (values.length != 3) throw new RuntimeException("Lock parameter invalid"); long position = Long.parseLong(values[0]); long size = Long.parseLong(values[1]); boolean shared = Boolean.parseBoolean(values[2]); fl = fc.lock(position, size, shared); } } if (cmd.equals(UNLOCK_CMD)) { if (fl == null) throw new RuntimeException("Not holding lock"); fl.release(); fl = null; } // send reply byte[] reply = { TERMINATOR }; n = sc.write(ByteBuffer.wrap(reply)); } } finally { sc.close(); if (fc != null) fc.close(); } } }