question: private int moveComponents ( Container target , int x , int y , int width , int height , int rowStart , int rowEnd , boolean ltr , boolean useBaseline , int [ ] ascent , int [ ] descent ) { switch ( newAlign ) { case LEFT : x += ltr ? 0 : width ; break ; case CENTER : x += width / 2 ; break ; case RIGHT : x += ltr ? width : 0 ; break ; case LEADING : break ; case TRAILING : x += width ; break ; } int maxAscent = 0 ; int nonbaselineHeight = 0 ; int baselineOffset = 0 ; if ( useBaseline ) { int maxDescent = 0 ; for ( int i = rowStart ; i < rowEnd ; i ++ ) { Component m = target . getComponent ( i ) ; if ( m . visible ) { if ( ascent [ i ] >= 0 ) { maxAscent = Math . max ( maxAscent , ascent [ i ] ) ; maxDescent = Math . max ( maxDescent , descent [ i ] ) ; } else { nonbaselineHeight = Math . max ( m . getHeight ( ) , nonbaselineHeight ) ; } } } height = Math . max ( maxAscent + maxDescent , nonbaselineHeight ) ; baselineOffset = ( height - maxAscent - maxDescent ) / 2 ; } for ( int i = rowStart ; i < rowEnd ; i ++ ) { Component m = target . getComponent ( i ) ; if ( m . isVisible ( ) ) { int cy ; if ( useBaseline && ascent [ i ] >= 0 ) { cy = y + baselineOffset + maxAscent - ascent [ i ] ; } else { cy = y + ( height - m . height ) / 2 ; } if ( ltr ) { m . setLocation ( x , cy ) ; } else { m . setLocation ( target . width - x - m . width , cy ) ; } x += m . width + hgap ; } } return height ; }
target:  Centers the elements in the specified row, if there is any slack.