core/src/main/java/com/orientechnologies/orient/core/record/ORecordAbstract.java
protected void removeListener(final ORecordListener listener) {
    if (_listeners != null) {
      _listeners.remove(listener);
      if (_listeners.isEmpty())
        _listeners = null;
    }
  }
protected void removeListener(final ORecordListener listener) {
    if (_listeners != null) {
      _listeners.remove(listener);
      if (_listeners.isEmpty())
        _listeners = null;
    }
  }
Remove the current event listener.

@see ORecordListener