public void deleteTrigger(String mappingName, Trigger trigger) {
        Mapping mapping = mappings.get(mappingName);
        if (mapping == null) {
            throw new IllegalArgumentException("Cannot find mapping: " + mappingName);
        }

        ArrayList<Mapping> maps = bindings.get(trigger.triggerHashCode());
        maps.remove(mapping);

    }
Deletes a specific trigger registered to a mapping.

<p>
The given mapping will no longer receive events raised by the
trigger.

@param mappingName The mapping name to cease receiving events from the
trigger.
@param trigger The trigger to no longer invoke events on the mapping.
jme3-core/src/main/java/com/jme3/input/InputManager.java