b = new JButton ("Calcola LCS");
c = new JButton ("Descrizione");
d = new JButton ("Esci");
e = new JButton ("Matrice 1");
f = new JButton ("Matrice 2");
p = new JPanel ();


b.addActionListener(this);
c.addActionListener(this);
d.addActionListener(this);
e.addActionListener(this);
f.addActionListener(this);

b.addKeyListener(new KeyAdapter()
{
public void keyPressed(KeyEvent ke)
{
if(ke.getKeyChar() == KeyEvent.VK_ENTER)
{
JButton sorgente = (JButton)ke.getSource();
sorgente.doClick();
} else if(ke.getKeyChar() == KeyEvent.VK_SPACE)
{
ke.consume();
}
}
});
add(b);

p.add(l);
p.add(text);
p.add(l1);
p.add(text2);
p.add(l2);
p.add(text3);
p.add(text4);
p.add(b);
p.add(c);
p.add(d);
p.add(e);
p.add(f);

getContentPane().add(p);
}

public void actionPerformed (ActionEvent event)
{


Object source = event.getSource(); //Bottone CALCOLA
if(source == b){

s1 = text.getText();
s2 = text2.getText();

if(s1.equals("") || s2.equals("")){
JOptionPane.showMessageDialog(null,"Devi inserire entrambe le stringhe!");

}
else{
LCS lcs1 = new LCS(s1,s2);
int mat[][]=new int[s1.length()][s2.length()];
mat=lcs1.AlgoritmoLCS(s1,s2);
text3.setText(Integer.toString(mat[s1.length()][s2.length()]));
text4.setText(lcs1.stampaLCS(s1,s2));
}
}



funziona solo se prima clicco sul bottone normalemte.
se invece clicco subito invio non fa nulla