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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 );