flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatTabbedPaneUI.java
protected boolean isContentEmpty() {
			int tabCount = tabPane.getTabCount();
			if( tabCount == 0 )
				return false;

			for( int i = 0; i < tabCount; i++ ) {
				Component c = tabPane.getComponentAt( i );
				if( c != null ) {
					Dimension cs = c.getPreferredSize();
					if( cs.width != 0 || cs.height != 0 )
						return false;
				}
			}

			return true;
		}
/**
		 * Check whether all content components are either {@code null} or have zero preferred size.
		 * <p>
		 * If {@code true}, assume that the tabbed pane is used without any content and
		 * use the size of the tab area (single run) as minimum/preferred size.
		 */
Check whether all content components are either  null or have zero preferred size.

If  true, assume that the tabbed pane is used without any content and
use the size of the tab area (single run) as minimum/preferred size.
Check whether all content components are either null or have zero preferred size . If true assume that the tabbed pane is used without any content and use the size of the tab area ( single run ) as minimum / preferred size .
protected boolean isContentEmpty() {
			int tabCount = tabPane.getTabCount();
			if( tabCount == 0 )
				return false;
			for( int i = 0; i < tabCount; i++ ) {
				Component c = tabPane.getComponentAt( i );
				if( c != null ) {
					Dimension cs = c.getPreferredSize();
					if( cs.width != 0 || cs.height != 0 )
						return false;
				}
			}
			return true;
		}
protected boolean isContentEmpty ( ) { int tabCount = tabPane . getTabCount ( ) ; if ( tabCount == 0 ) return false ; for ( int i = 0 ; i < tabCount ; i ++ ) { Component c = tabPane . getComponentAt ( i ) ; if ( c != null ) { Dimension cs = c . getPreferredSize ( ) ; if ( cs . width != 0 || cs . height != 0 ) return false ; } } return true ; }
Check whether all content components are either {@code null} or have zero preferred size.
Check whether all content components are either { @code null } or have zero preferred size .