Semaphore (Quartz Enterprise Job Scheduler 2.5.1 API)

All Known Implementing Classes:

DBSemaphore, JTANonClusteredSemaphore, SimpleSemaphore, StdRowLockSemaphore, UpdateLockRowSemaphore
```
public interface Semaphore
```
An interface for providing thread/resource locking in order to protect resources from being altered by multiple threads at the same time.

Author:

jhouse

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`boolean`	`obtainLock(java.sql.Connection conn, java.lang.String lockName)`	Grants a lock on the identified resource to the calling thread (blocking until it is available).
`void`	`releaseLock(java.lang.String lockName)`	Release the lock on the identified resource if it is held by the calling thread.
`boolean`	`requiresConnection()`	Whether this Semaphore implementation requires a database connection for its lock management operations.

- Method Detail
  - obtainLock
```
boolean obtainLock(java.sql.Connection conn,
                   java.lang.String lockName)
            throws LockException
```
    Grants a lock on the identified resource to the calling thread (blocking until it is available).
    
    Parameters:
    
    conn - Database connection used to establish lock. Can be null if requiresConnection() returns false.
    
    Returns:
    
    true if the lock was obtained.
    
    Throws:
    
    LockException
  - releaseLock
```
void releaseLock(java.lang.String lockName)
          throws LockException
```
    Release the lock on the identified resource if it is held by the calling thread.
    
    Throws:
    
    LockException
  - requiresConnection
```
boolean requiresConnection()
```
    Whether this Semaphore implementation requires a database connection for its lock management operations.
    
    See Also:
    
    obtainLock(Connection, String), releaseLock(String)