package require java

java::import javax.swing.JFrame
java::import javax.swing.JLabel

set frame [java::new JFrame] 
$frame setDefaultCloseOperation [java::field JFrame EXIT_ON_CLOSE]
$frame setTitle "Hello, World"
$frame setSize 640 480
set label [java::new JLabel "Hello, Swing World!"] 
$label setVerticalAlignment [java::field JLabel TOP]
$frame add $label
$frame setVisible true

vwait done