logback-android/src/main/java/ch/qos/logback/classic/util/LogbackMDCAdapter.java
public Set<String> getKeys() {
    Map<String, String> map = getPropertyMap();

    if (map != null) {
      return map.keySet();
    } else {
      return null;
    }
  }
public Set<String> getKeys() {
    Map<String, String> map = getPropertyMap();

    if (map != null) {
      return map.keySet();
    } else {
      return null;
    }
  }
public Set < String > getKeys ( ) { Map < String , String > map = getPropertyMap ( ) ; if ( map != null ) { return map . keySet ( ) ; } else { return null ; } }
Returns the keys in the MDC as a {@link Set}. The returned value can be
null.
Returns the keys in the MDC as a {