Decrement by 1, return current

Atomically decrements by one the current value and returns the updated (current) value of the counter. Multiple concurrent client requests are guaranteed to return unique updated value.

// *******************************************
// synchronous methods
// *******************************************

// Backendless.Counters approach
public Long Backendless.Counters.decrementAndGet( String counterName );

// IAtomic approach
IAtomic<T> counter = Backendless.Counters.of( String counterName, 
                                                    Class<? extends T> type );
public T counter.decrementAndGet();

// *******************************************
// asynchronous methods
// *******************************************

// Backendless.Counters approach
public <T> T Backendless.Counters.incrementAndGet( String counterName, 
                                                         AsyncCallback<T> callback );

// IAtomic approach
IAtomic<T> counter = Backendless.Counters.of( String counterName, 
                                                    Class<? extends T> type );
public T counter.decrementAndGet( AsyncCallback<T> callback );

where:

Argument	Description
counterName	name of the counter to decrement.
type	numeric type for the counter values. Can be an instance of Byte.class, Short.class, Integer.class, Float.class, Long.class and Double.class.
callback	the callback used for asynchronous calls to indicate that the operation has either successfully completed or resulted in error.

Example

AsyncCallback<Integer> callback = new AsyncCallback<Integer>()
{
  @Override
  public void handleResponse( Integer value )
  {
    Log.i( "MYAPP", "[ASYNC] current counter value is - " + value );
  }

  @Override
  public void handleFault( BackendlessFault backendlessFault )
  {
    Log.e( "MYAPP", "Error - " + backendlessFault.getMessage() );
  }
};

Backendless.Counters.decrementAndGet( "my counter", callback );

IAtomic<Integer> myCounter = Backendless.Counters.of( "my counter", Integer.class );
int counterValue = myCounter.decrementAndGet();
Log.i( "MYAPP", "[SYNC] current counter value is - " + counterValue );

Codeless Reference

where:

Argument	Description
counter name	Name of the counter whose value must be decremented.
return current value	When this box is checked, the operation returns the current value of the counter.

Returns the current value of the counter.

Consider the following counter:

The example below decrements the value of the "CarsParkingLot" by 1. This operation returns 9, since the return current value box is checked.

The result of this operation will look as shown below after the Codeless logic runs: