public void setState( State state ) {
		if( this.state == state )
			return;

		State oldState = this.state;
		this.state = state;

		putClientProperty( SELECTED_STATE, (state == State.INDETERMINATE) ? SELECTED_STATE_INDETERMINATE : null );

		firePropertyChange( "state", oldState, state );
		repaint();
	}
Sets the state as {@link State} enum.
flatlaf-extras/src/main/java/com/formdev/flatlaf/extras/components/FlatTriStateCheckBox.java