SemaphoreWithOwners (Apache Brooklyn)

java.lang.Object
- java.util.concurrent.Semaphore
- - brooklyn.util.mutex.SemaphoreWithOwners

All Implemented Interfaces:

java.io.Serializable

Direct Known Subclasses:

SemaphoreForTasks
```
public class SemaphoreWithOwners
extends java.util.concurrent.Semaphore
```
a subclass of Semaphore which tracks who created and released the semaphores, and which requires the same thread to release as created it.

See Also:
Serialized Form

Constructor Summary

Constructors
Constructor and Description
`SemaphoreWithOwners(java.lang.String name)`
`SemaphoreWithOwners(java.lang.String name, int permits, boolean fair)`

Method Summary

Methods
Modifier and Type	Method and Description
`void`	`acquire()`
`void`	`acquire(int permits)`
`void`	`acquireUnchecked()`
`void`	`acquireUnchecked(int numPermits)`
`void`	`acquireUninterruptibly()`
`void`	`acquireUninterruptibly(int permits)`
`java.lang.String`	`getDescription()` caller supplied description
`java.lang.String`	`getName()` constructor-time supplied name
`java.util.List<java.lang.Thread>`	`getOwningThreads()` unmodifiable view of threads owning the permits; threads with multiple permits listed multiply
`java.util.List<java.lang.Thread>`	`getRequestingThreads()` unmodifiable view of threads requesting access (blocked or briefly trying to acquire); this is guaranteed to be cleared _after_ getOwners (synchronizing on this class while reading both fields will give canonical access)
`void`	`indicateCallingThreadWillRequest()` Indicate that the calling thread is going to acquire or tryAcquire, in order to set up the semaphore's isInUse() value appropriately for certain checks.
`boolean`	`isCallingThreadAnOwner()` true iff the calling thread is one of the owners
`boolean`	`isInUse()` true iff there are any owners or any requesters (callers blocked trying to acquire)
`void`	`release()`
`void`	`release(int permits)`
`void`	`setDescription(java.lang.String description)`
`java.lang.String`	`toString()`
`boolean`	`tryAcquire()`
`boolean`	`tryAcquire(int permits)`
`boolean`	`tryAcquire(int permits, long timeout, java.util.concurrent.TimeUnit unit)`
`boolean`	`tryAcquire(long timeout, java.util.concurrent.TimeUnit unit)`

Methods inherited from class java.util.concurrent.Semaphore
availablePermits, drainPermits, getQueueLength, hasQueuedThreads, isFair

Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Constructor Detail
  - SemaphoreWithOwners
```
public SemaphoreWithOwners(java.lang.String name)
```
  - SemaphoreWithOwners
```
public SemaphoreWithOwners(java.lang.String name,
                   int permits,
                   boolean fair)
```
- Method Detail
  - acquire
```
public void acquire()
             throws java.lang.InterruptedException
```
    Overrides:
    
    acquire in class java.util.concurrent.Semaphore
    
    Throws:
    
    java.lang.InterruptedException
  - acquire
```
public void acquire(int permits)
             throws java.lang.InterruptedException
```
    Overrides:
    
    acquire in class java.util.concurrent.Semaphore
    
    Throws:
    
    java.lang.InterruptedException
  - acquireUninterruptibly
```
public void acquireUninterruptibly()
```
    Overrides:
    
    acquireUninterruptibly in class java.util.concurrent.Semaphore
  - acquireUninterruptibly
```
public void acquireUninterruptibly(int permits)
```
    Overrides:
    
    acquireUninterruptibly in class java.util.concurrent.Semaphore
  - acquireUnchecked
```
public void acquireUnchecked()
```
  - acquireUnchecked
```
public void acquireUnchecked(int numPermits)
```
  - tryAcquire
```
public boolean tryAcquire()
```
    Overrides:
    
    tryAcquire in class java.util.concurrent.Semaphore
  - tryAcquire
```
public boolean tryAcquire(int permits)
```
    Overrides:
    
    tryAcquire in class java.util.concurrent.Semaphore
  - tryAcquire
```
public boolean tryAcquire(int permits,
                 long timeout,
                 java.util.concurrent.TimeUnit unit)
                   throws java.lang.InterruptedException
```
    Overrides:
    
    tryAcquire in class java.util.concurrent.Semaphore
    
    Throws:
    
    java.lang.InterruptedException
  - tryAcquire
```
public boolean tryAcquire(long timeout,
                 java.util.concurrent.TimeUnit unit)
                   throws java.lang.InterruptedException
```
    Overrides:
    
    tryAcquire in class java.util.concurrent.Semaphore
    
    Throws:
    
    java.lang.InterruptedException
  - release
```
public void release()
```
    Overrides:
    
    release in class java.util.concurrent.Semaphore
  - release
```
public void release(int permits)
```
    Overrides:
    
    release in class java.util.concurrent.Semaphore
  - isInUse
```
public boolean isInUse()
```
    true iff there are any owners or any requesters (callers blocked trying to acquire)
  - isCallingThreadAnOwner
```
public boolean isCallingThreadAnOwner()
```
    true iff the calling thread is one of the owners
  - getName
```
public java.lang.String getName()
```
    constructor-time supplied name
  - setDescription
```
public void setDescription(java.lang.String description)
```
  - getDescription
```
public java.lang.String getDescription()
```
    caller supplied description
  - getOwningThreads
```
public java.util.List<java.lang.Thread> getOwningThreads()
```
    unmodifiable view of threads owning the permits; threads with multiple permits listed multiply
  - getRequestingThreads
```
public java.util.List<java.lang.Thread> getRequestingThreads()
```
    unmodifiable view of threads requesting access (blocked or briefly trying to acquire); this is guaranteed to be cleared _after_ getOwners (synchronizing on this class while reading both fields will give canonical access)
  - toString
```
public java.lang.String toString()
```
    Overrides:
    
    toString in class java.util.concurrent.Semaphore
  - indicateCallingThreadWillRequest
```
public void indicateCallingThreadWillRequest()
```
    Indicate that the calling thread is going to acquire or tryAcquire, in order to set up the semaphore's isInUse() value appropriately for certain checks. It *must* do so after invoking this method.

Class SemaphoreWithOwners

Constructor Summary

Method Summary

Methods inherited from class java.util.concurrent.Semaphore

Methods inherited from class java.lang.Object

Constructor Detail

SemaphoreWithOwners

SemaphoreWithOwners

Method Detail

acquire

acquire

acquireUninterruptibly

acquireUninterruptibly

acquireUnchecked

acquireUnchecked

tryAcquire

tryAcquire

tryAcquire

tryAcquire

release

release

isInUse

isCallingThreadAnOwner

getName

setDescription

getDescription

getOwningThreads

getRequestingThreads

toString

indicateCallingThreadWillRequest