You can put a JTextArea in a JOptionPane. You can also put a JScrollPane in a JOptionPane.
JTextArea myTArea= new JTextArea(17, 20);
JScrollPane myScroller=new JScrollPane( myTArea);
String longText="jadda jadda... jadda jadda";
myTArea.setText(longText);
JOptionPane.show...(myParentContainer, myScroller, myTitle, JOptionPane.PLAIN_MESSAGE);