From 410fcb6242d1dcf98d6f4eb94f9409d656fc0caa Mon Sep 17 00:00:00 2001 From: Sven Gothel Date: Sat, 11 Jun 2011 01:56:29 +0200 Subject: Complete relocation of SingletonInstance.java from JOGL --- .../common/util/locks/SingletonInstance.java | 164 +++++++++++++++++++++ 1 file changed, 164 insertions(+) create mode 100644 src/java/com/jogamp/common/util/locks/SingletonInstance.java (limited to 'src/java/com/jogamp/common') diff --git a/src/java/com/jogamp/common/util/locks/SingletonInstance.java b/src/java/com/jogamp/common/util/locks/SingletonInstance.java new file mode 100644 index 0000000..f69641f --- /dev/null +++ b/src/java/com/jogamp/common/util/locks/SingletonInstance.java @@ -0,0 +1,164 @@ +/** + * Copyright 2010 JogAmp Community. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without modification, are + * permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright notice, this list of + * conditions and the following disclaimer. + * + * 2. Redistributions in binary form must reproduce the above copyright notice, this list + * of conditions and the following disclaimer in the documentation and/or other materials + * provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY JogAmp Community ``AS IS'' AND ANY EXPRESS OR IMPLIED + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND + * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JogAmp Community OR + * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR + * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON + * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING + * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF + * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * The views and conclusions contained in the software and documentation are those of the + * authors and should not be interpreted as representing official policies, either expressed + * or implied, of JogAmp Community. + */ + +package com.jogamp.common.util.locks; + +import java.io.File; +import java.io.IOException; +import java.io.RandomAccessFile; +import java.nio.channels.FileLock; +import java.util.Date; + +public class SingletonInstance { + + static final boolean DEBUG = true; + static final String temp_file_path; + + static { + String s = null; + try { + File tmpFile = File.createTempFile("TEST", "tst"); + String absTmpFile = tmpFile.getCanonicalPath(); + tmpFile.delete(); + s = absTmpFile.substring(0, absTmpFile.lastIndexOf(File.separator)); + } catch (IOException ex) { + ex.printStackTrace(); + } + temp_file_path = s; + } + + public static String getCanonicalTempPath() { + return temp_file_path; + } + + public static String getCanonicalTempLockFilePath(String basename) { + return getCanonicalTempPath() + File.separator + basename; + } + + public SingletonInstance(String name, String lockFileBasename) { + this.name = name; + this.file = new File ( getCanonicalTempLockFilePath ( lockFileBasename ) ); + setupFileCleanup(); + } + + public SingletonInstance(String name, File lockFile) { + this.name = name; + this.file = lockFile ; + setupFileCleanup(); + } + + public String getName() { return name; } + + void setupFileCleanup() { + file.deleteOnExit(); + Runtime.getRuntime().addShutdownHook(new Thread() { + public void run() { + unlock(); + } + }); + } + + public synchronized void lock(long timeout_ms, long poll_ms) { + long i=0; + try { + do { + if(tryLock()) { + return; + } + if(DEBUG && 0==i) { + System.err.println("SLOCK "+System.currentTimeMillis()+" ??? "+name+" - Wait for lock " + file); + } + i++; + Thread.sleep(poll_ms); + } while ( i < timeout_ms / poll_ms ) ; + } catch ( InterruptedException ie ) { + throw new RuntimeException(ie); + } + throw new RuntimeException("SLOCK "+System.currentTimeMillis()+" EEE "+name+" - couldn't get lock within "+timeout_ms+"ms"); + } + + public synchronized boolean tryLock() { + try { + randomAccessFile = new RandomAccessFile(file, "rw"); + fileLock = randomAccessFile.getChannel().tryLock(); + + if (fileLock != null) { + locked = true; + if(DEBUG) { + System.err.println("SLOCK "+System.currentTimeMillis()+" +++ "+name+" - Locked " + file); + } + return true; + } + } catch (Exception e) { + System.err.println("SLOCK "+System.currentTimeMillis()+" EEE "+name+" - Unable to create and/or lock file: " + file); + e.printStackTrace(); + } + return false; + } + + public synchronized boolean unlock() { + try { + if(null != fileLock) { + if(locked) { + fileLock.release(); + if(DEBUG) { + System.err.println("SLOCK "+System.currentTimeMillis()+" --- "+name+" - Unlocked " + file); + } + } + fileLock = null; + } + if(null != randomAccessFile) { + randomAccessFile.close(); + randomAccessFile = null; + } + if(null != file) { + file.delete(); + file = null; + } + return true; + } catch (Exception e) { + System.err.println("SLOCK "+System.currentTimeMillis()+" EEE "+name+" - Unable to remove lock file: " + file); + e.printStackTrace(); + } finally { + fileLock = null; + randomAccessFile = null; + locked = false; + } + return false; + } + + public synchronized boolean isLocked() { + return locked; + } + + String name; + File file = null; + RandomAccessFile randomAccessFile = null; + FileLock fileLock = null; + boolean locked = false; +} -- cgit v1.2.3