LockMiddleware (rqueue-core 2.7.0-RELEASE API)

All Superinterfaces:

Middleware, TimeProviderMiddleware

All Known Implementing Classes:

RedisLockMiddleware
```
public interface LockMiddleware
extends TimeProviderMiddleware
```
Lock middleware can be used for locking purpose Use cases:
User's wallet amount should not be updated in parallel, in that case a lock on user's wallet account can be acquired to avoid parallel execution of task.
Only one task for a queue should be running at any point of time, in that case lock on the given queue can be acquired.

Field Summary

Fields
Modifier and Type Field Description

static java.lang.String REASON
- Fields inherited from interface com.github.sonus21.rqueue.core.middleware.TimeProviderMiddleware
  ONE_SECOND

Method Summary

All Methods Instance Methods Abstract Methods Default Methods
Modifier and Type	Method	Description
`java.lang.String`	`acquireLock(Job job)`	This method should acquire lock from any source like Redis, File, Java Lock or any system and returns lock identifier for the same.
`default void`	`handle(Job job, java.util.concurrent.Callable<java.lang.Void> callable)`	Middleware handles that would be called
`void`	`releaseLock(Job job, java.lang.String lockIdentifier)`	This method id called to release lock acquired using `acquireLock(Job)`.

Methods inherited from interface com.github.sonus21.rqueue.core.middleware.TimeProviderMiddleware
releaseIn

- Field Detail
  - REASON
```
static final java.lang.String REASON
```
    See Also:
    
    Constant Field Values
- Method Detail
  - acquireLock
```
java.lang.String acquireLock(Job job)
```
    This method should acquire lock from any source like Redis, File, Java Lock or any system and returns lock identifier for the same. If it's unable to acquire lock than this method must return null/empty string.If locking system does not support lock identifier than you can return Job.getId().
    
    Parameters:
    
    job - running job object
    
    Returns:
    
    lock identifier
  - releaseLock
```
void releaseLock(Job job,
                 java.lang.String lockIdentifier)
```
    This method id called to release lock acquired using acquireLock(Job).
    This method is always called
    
    Parameters:
    
    job - the running job
    
    lockIdentifier - lock identifier
  - handle
```
default void handle(Job job,
                    java.util.concurrent.Callable<java.lang.Void> callable)
             throws java.lang.Exception
```
    Description copied from interface: Middleware
    
    Middleware handles that would be called
    
    Specified by:
    
    handle in interface Middleware
    
    Parameters:
    
    job - job object
    
    callable - next middleware in chain
    
    Throws:
    
    java.lang.Exception - any exception