The program doesn't end when player 1 life reaches 0

I'm making a little game using the Java Swing, in which there are four bottoms: attack player 1, attack player 2, regenerate player 1, regenerate player 2. When attack player 1 or attack player 2 push bottom are pressed, it removes -25 from the life of the player, vice versa, when regenerate bottoms are pressed it adds +15 to player's life. Now, everything works perfectly here, but when life reaches zero, the player is dead and the label text changes in: "Player 1 is dead" or "Player2 is dead", but this never happens:

as you can see from the picture, player 1 life has been incremented and player 2 life even reached -50, this is the code:

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class Swing16 implements ActionListener {
static int life1 = 100;
static int life2 = 100;
JLabel AttRig;
Swing16() {
// Imposta le impostazioni del frame
JFrame jfrm = new JFrame("game");
// Layout basico
jfrm.setLayout(new FlowLayout());
// Grandezza del frame (500 x 500).
jfrm.setSize(500, 500);
// Esci dal programma se l'utente esce dal frame.
jfrm.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JButton attacca1  = new JButton("Attack player one (-25)"); //Attack player two (-25)
JButton rigenera1 = new JButton("Attack player two (-25)"); // Regenerate player one (+15)
JButton attacca2  = new JButton("Regenerate player one (+15)"); // Attack player one (-25)
JButton rigenera2 = new JButton("Regenerate player two (+15)");
// Aggiungi action listeners per i push bottom.
attacca1.addActionListener(this);
attacca2.addActionListener(this); // rigenera1.addActionListener(this);
rigenera1.addActionListener(this);
rigenera2.addActionListener(this);
// Aggiung pulsanti.
jfrm.add(attacca1);
jfrm.add(attacca2);
jfrm.add(rigenera1);
jfrm.add(rigenera2);
// Nuovo label.
AttRig = new JLabel("Player 1 life: 100 | Player 2 life: 100");
// Aggiungi label al frame 
jfrm.add(AttRig);
// Visibilità del frame 
jfrm.setVisible(true);
}
// Cosa succede se i bottoni vengono cliccati.
public void actionPerformed(ActionEvent e) {
if(e.getActionCommand().equals("Attack player two (-25)")) {
life2 = life2 - 25;
AttRig.setText("Player 1 life: " + life1 + " | " + "Player 2 life: " + life2);
}
else if(e.getActionCommand().equals("Regenerate player one (+15)")){
life1 = life1 + 15;
AttRig.setText("Player 1 life: " + life1 + " | " + "Player 2 life: " + life2);
}
else if(e.getActionCommand().equals("Attack player one (-25)")) {
life1 = life1 - 25;
AttRig.setText("Player 1 life: " + life1 + " | " + "Player 2 life: " + life2);
}
else if(e.getActionCommand().equals("Regenerate player two (+15)")) {
life2 = life2 + 15;
AttRig.setText("Player 1 life: " + life1 + " | " + "Player 2 life: " + life2);
}	
else if(life1 < 0) {
AttRig.setText("Player 1 dies...");
}
else if(life2 < 0) {
AttRig.setText("Player 2 dies...");
}
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
new Swing16();
}
});
}
}

what may I do make restart the program through another push bottom? Thank you very much.

You should check the life values after(!) you changed them.

In public void actionPerformed(ActionEvent e) method, the following else if part should be 2 separate if statements as follows:

        if(life1 < 0) {
AttRig.setText("Player 1 dies...");
}
if(life2 < 0) {
AttRig.setText("Player 2 dies...");
}

So it should look like this:

 public void actionPerformed(ActionEvent e) {
if(e.getActionCommand().equals("Attack player two (-25)")) {
life2 = life2 - 25;
AttRig.setText("Player 1 life: " + life1 + " | " + "Player 2 life: " + life2);
}
else if(e.getActionCommand().equals("Regenerate player one (+15)")){
life1 = life1 + 15;
AttRig.setText("Player 1 life: " + life1 + " | " + "Player 2 life: " + life2);
}
else if(e.getActionCommand().equals("Attack player one (-25)")) {
life1 = life1 - 25;
AttRig.setText("Player 1 life: " + life1 + " | " + "Player 2 life: " + life2);
}
else if(e.getActionCommand().equals("Regenerate player two (+15)")) {
life2 = life2 + 15;
AttRig.setText("Player 1 life: " + life1 + " | " + "Player 2 life: " + life2);
}   
if(life1 < 0) {
AttRig.setText("Player 1 dies...");
}
if(life2 < 0) {
AttRig.setText("Player 2 dies...");
}
}