| 68 | 1 /* | 
|  | 2 Copyright (c) 2008  Franklin Schmidt <fschmidt@gmail.com> | 
|  | 3 | 
|  | 4 Permission is hereby granted, free of charge, to any person obtaining a copy | 
|  | 5 of this software and associated documentation files (the "Software"), to deal | 
|  | 6 in the Software without restriction, including without limitation the rights | 
|  | 7 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell | 
|  | 8 copies of the Software, and to permit persons to whom the Software is | 
|  | 9 furnished to do so, subject to the following conditions: | 
|  | 10 | 
|  | 11 The above copyright notice and this permission notice shall be included in | 
|  | 12 all copies or substantial portions of the Software. | 
|  | 13 | 
|  | 14 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | 
|  | 15 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | 
|  | 16 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE | 
|  | 17 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER | 
|  | 18 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, | 
|  | 19 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN | 
|  | 20 THE SOFTWARE. | 
|  | 21 */ | 
|  | 22 | 
|  | 23 package fschmidt.util.locks; | 
|  | 24 | 
|  | 25 import java.util.Set; | 
|  | 26 import java.util.HashSet; | 
|  | 27 import java.util.Collections; | 
|  | 28 import java.util.concurrent.TimeUnit; | 
|  | 29 import java.util.concurrent.locks.Lock; | 
|  | 30 import org.slf4j.Logger; | 
|  | 31 import org.slf4j.LoggerFactory; | 
|  | 32 | 
|  | 33 | 
|  | 34 public final class TimedLock extends ProxyLock { | 
|  | 35 	private static final Logger logger = LoggerFactory.getLogger(TimedLock.class); | 
|  | 36 | 
|  | 37 	private static long timeoutDefault = 10L*60L*1000L;  // 10 minutes | 
|  | 38 	private static long waitTimeDefault = 60L*1000L;  // 1 minutes | 
|  | 39 | 
|  | 40 	public static long getTimeoutDefault() { | 
|  | 41 		return timeoutDefault; | 
|  | 42 	} | 
|  | 43 | 
|  | 44 	public static void setTimeoutDefault(long timeoutDefault) { | 
|  | 45 		TimedLock.timeoutDefault = timeoutDefault; | 
|  | 46 	} | 
|  | 47 | 
|  | 48 	public static long getWaitTimeDefault() { | 
|  | 49 		return waitTimeDefault; | 
|  | 50 	} | 
|  | 51 | 
|  | 52 	public static void setWaitTimeDefault(long waitTimeDefault) { | 
|  | 53 		TimedLock.waitTimeDefault = waitTimeDefault; | 
|  | 54 	} | 
|  | 55 | 
|  | 56 	private static Set<TimedLock> locks = Collections.synchronizedSet(new HashSet<TimedLock>()); | 
|  | 57 	private int count = 0; | 
|  | 58 	private final Object sync = new Object(); | 
|  | 59 	private long whenLocked; | 
|  | 60 	private long whenChecked; | 
|  | 61 	private long timeout = timeoutDefault; | 
|  | 62 	private long waitTime = waitTimeDefault; | 
|  | 63 	private Thread thread = null; | 
|  | 64 | 
|  | 65 	public TimedLock(Lock lock) { | 
|  | 66 		super(lock); | 
|  | 67 	} | 
|  | 68 | 
|  | 69 	public long getTimeout() { | 
|  | 70 		return timeout; | 
|  | 71 	} | 
|  | 72 | 
|  | 73 	public void setTimeout(long timeout) { | 
|  | 74 		this.timeout = timeout; | 
|  | 75 	} | 
|  | 76 | 
|  | 77 	public long getWaitTime() { | 
|  | 78 		return waitTime; | 
|  | 79 	} | 
|  | 80 | 
|  | 81 	public void setWaitTime(long waitTime) { | 
|  | 82 		this.waitTime = waitTime; | 
|  | 83 	} | 
|  | 84 | 
|  | 85 	private void locked() { | 
|  | 86 		synchronized(sync) { | 
|  | 87 			if( count++ == 0 ) { | 
|  | 88 				whenLocked = System.currentTimeMillis(); | 
|  | 89 				whenChecked = whenLocked; | 
|  | 90 				thread = Thread.currentThread(); | 
|  | 91 				if( !locks.add(this) ) | 
|  | 92 					throw new RuntimeException(); | 
|  | 93 			} | 
|  | 94 		} | 
|  | 95 	} | 
|  | 96 | 
|  | 97 	public boolean tryLock() { | 
|  | 98 		if( !super.tryLock() ) | 
|  | 99 			return false; | 
|  | 100 		locked(); | 
|  | 101 		return true; | 
|  | 102 	} | 
|  | 103 | 
|  | 104 	public boolean tryLock(long time,TimeUnit unit) | 
|  | 105 		throws InterruptedException | 
|  | 106 	{ | 
|  | 107 		long t = TimeUnit.MILLISECONDS.convert(time,unit); | 
|  | 108 		while( t > waitTime ) { | 
|  | 109 			if( super.tryLock(waitTime,TimeUnit.MILLISECONDS) ) { | 
|  | 110 				locked(); | 
|  | 111 				return true; | 
|  | 112 			} | 
|  | 113 			t -= waitTime; | 
|  | 114 			check(); | 
|  | 115 		} | 
|  | 116 		if( super.tryLock(t,TimeUnit.MILLISECONDS) ) { | 
|  | 117 			locked(); | 
|  | 118 			return true; | 
|  | 119 		} | 
|  | 120 		return false; | 
|  | 121 	} | 
|  | 122 | 
|  | 123 	public void lockInterruptibly() | 
|  | 124 		throws InterruptedException | 
|  | 125 	{ | 
|  | 126 		while(true) { | 
|  | 127 			if( super.tryLock(waitTime,TimeUnit.MILLISECONDS) ) { | 
|  | 128 				locked(); | 
|  | 129 				return; | 
|  | 130 			} | 
|  | 131 			check(); | 
|  | 132 		} | 
|  | 133 	} | 
|  | 134 | 
|  | 135 	public void lock() { | 
|  | 136 		try { | 
|  | 137 			lockInterruptibly(); | 
|  | 138 		} catch(InterruptedException e) { | 
|  | 139 			throw new RuntimeException(e); | 
|  | 140 		} | 
|  | 141 	} | 
|  | 142 | 
|  | 143 	public void unlock() { | 
|  | 144 		synchronized(sync) { | 
|  | 145 			if( --count == 0 ) { | 
|  | 146 				if( !locks.remove(this) ) | 
|  | 147 					throw new RuntimeException(); | 
|  | 148 				thread = null; | 
|  | 149 			} | 
|  | 150 		} | 
|  | 151 		super.unlock(); | 
|  | 152 	} | 
|  | 153 | 
|  | 154 	private void check() { | 
|  | 155 		long now = System.currentTimeMillis(); | 
|  | 156 		long tooOld = now - timeout; | 
|  | 157 		TimedLock[] a = locks.toArray(new TimedLock[0]); | 
|  | 158 		for( int i=0; i<a.length; i++ ) { | 
|  | 159 			TimedLock tl = a[i]; | 
|  | 160 			if( tl.whenChecked < tooOld ) { | 
|  | 161 				StringBuilder buf = new StringBuilder(); | 
|  | 162 				buf.append("lock "+tl+" timed out, locked for "+(System.currentTimeMillis()-tl.whenLocked)+" millis"); | 
|  | 163 				buf.append("\n"+tl.thread); | 
|  | 164 				for( StackTraceElement ste : tl.thread.getStackTrace() ) { | 
|  | 165 					buf.append("\n\t"+ste); | 
|  | 166 				} | 
|  | 167 				logger.error(buf.toString()); | 
|  | 168 				tl.whenChecked = now; | 
|  | 169 			} | 
|  | 170 		} | 
|  | 171 	} | 
|  | 172 | 
|  | 173 } |