Dmitry Jemerov
66 lines
1.6 KiB
Kotlin
66 lines
1.6 KiB
Kotlin
package kotlin.concurrent
|
|
|
|
import java.util.concurrent.locks.Lock
|
|
import java.util.concurrent.locks.ReentrantReadWriteLock
|
|
import java.util.concurrent.CountDownLatch
|
|
|
|
/**
|
|
* Executes the given [action] under this lock.
|
|
* @return the return value of the action.
|
|
*/
|
|
public inline fun <T> Lock.withLock(action: () -> T): T {
|
|
lock()
|
|
try {
|
|
return action()
|
|
} finally {
|
|
unlock();
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Executes the given [action] under the read lock of this lock.
|
|
* @return the return value of the action.
|
|
*/
|
|
public inline fun <T> ReentrantReadWriteLock.read(action: () -> T): T {
|
|
val rl = readLock()
|
|
rl.lock()
|
|
try {
|
|
return action()
|
|
} finally {
|
|
rl.unlock()
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Executes the given [action] under the write lock of this lock.
|
|
* The method does upgrade from read to write lock if needed
|
|
* If such write has been initiated by checking some condition, the condition must be rechecked inside the action to avoid possible races
|
|
* @return the return value of the action.
|
|
*/
|
|
public inline fun <T> ReentrantReadWriteLock.write(action: () -> T): T {
|
|
val rl = readLock()
|
|
|
|
val readCount = if (getWriteHoldCount() == 0) getReadHoldCount() else 0
|
|
readCount times { rl.unlock() }
|
|
|
|
val wl = writeLock()
|
|
wl.lock()
|
|
try {
|
|
return action()
|
|
} finally {
|
|
readCount times { rl.lock() }
|
|
wl.unlock()
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Executes the given [action] and await for CountDownLatch
|
|
* @return the return value of the action.
|
|
*/
|
|
public fun <T> Int.latch(operation: CountDownLatch.() -> T): T {
|
|
val latch = CountDownLatch(this)
|
|
val result = latch.operation()
|
|
latch.await()
|
|
return result
|
|
}
|