diff --git a/DEV2.1/Evenement_suite/Playlist.class b/DEV2.1/Evenement_suite/Playlist.class
index 6f677ce..fcf7f96 100644
Binary files a/DEV2.1/Evenement_suite/Playlist.class and b/DEV2.1/Evenement_suite/Playlist.class differ
diff --git a/DEV2.1/Evenement_suite/Playlist.java b/DEV2.1/Evenement_suite/Playlist.java
index ee25b00..4048d60 100644
--- a/DEV2.1/Evenement_suite/Playlist.java
+++ b/DEV2.1/Evenement_suite/Playlist.java
@@ -1,32 +1,39 @@
 import javax.swing.*;
 import java.awt.*;
 import java.awt.event.*;
-import java.awt.Color.*;
 
-public class Playlist extends JFrame implements MouseListener{
+public class Playlist extends JFrame implements MouseListener {
+    
     @Override
-    void mouseClicked(MouseEvent evenement){
-        evenement.setBackground(COLOR.GREY);
-        repaint();
-    }
-    @Override
-    void mouseEntered(MouseEvent evenement){
-        evenement.setBackground(COLOR.CYAN);
-        repaint();
-    }
-    @Override
-    void mouseExited(MouseEvent evenement){
+    public void mouseClicked(MouseEvent e) {
+        this.setBackground(Color.LIGHT_GRAY);
         repaint();
     }
 
-    public static void main(String[] args) {
-        JFrame fenetre = new JFrame();
-        fenetre.setSize(300, 200);
-        fenetre.setTitle("Playlist");
-        GridLayout grid = new GridLayout(9, 1);
-        grid.setVgap(-15);
-        fenetre.setLayout(grid);
-        fenetre.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
+    @Override
+    public void mouseEntered(MouseEvent e) {
+        this.setBackground(Color.CYAN);
+        repaint();
+    }
+
+    @Override
+    public void mouseExited(MouseEvent e) {
+        this.setBackground(Color.WHITE);
+        repaint();
+    }
+
+    // Les méthodes suivantes ne sont pas utilisées mais doivent être implémentées en raison de l'interface MouseListener
+    @Override
+    public void mousePressed(MouseEvent e) {}
+
+    @Override
+    public void mouseReleased(MouseEvent e) {}
+
+    public Playlist() {
+        super("Playlist");
+        setSize(300, 200);
+        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
+        setLayout(new GridLayout(9, 1));
 
         JLabel mus1 = new JLabel("Speak To Me/Breathe");
         JLabel mus2 = new JLabel("On The Run");
@@ -38,24 +45,17 @@ public class Playlist extends JFrame implements MouseListener{
         JLabel mus8 = new JLabel("Brain Damage");
         JLabel mus9 = new JLabel("Eclipse");
 
-        JLabel[] tab = null;
-        tab = new JLabel[] {mus1,mus2,mus3,mus4,mus5,mus6,mus7,mus8,mus9};
+        JLabel[] tab = {mus1, mus2, mus3, mus4, mus5, mus6, mus7, mus8, mus9};
 
-        for (int i=0; i<9; i++){
-            mouseClicked(tab[i]);
-            mouseEntered(tab[i]);
-            mouseExited(tab[i]);
+        for (JLabel label : tab) {
+            label.addMouseListener(this);
+            add(label);
         }
 
-        fenetre.add(mus1);
-        fenetre.add(mus2);
-        fenetre.add(mus3);
-        fenetre.add(mus4);
-        fenetre.add(mus5);
-        fenetre.add(mus6);
-        fenetre.add(mus7);
-        fenetre.add(mus8);
-        fenetre.add(mus9);
-        fenetre.setVisible(true);
+        setVisible(true);
+    }
+
+    public static void main(String[] args) {
+        Playlist play = new Playlist();
     }
 }
\ No newline at end of file
diff --git a/DEV2.1/Exception/ex1/NullPointerException.java b/DEV2.1/Exception/ex1/NullPointerException.java
new file mode 100644
index 0000000..5649d20
--- /dev/null
+++ b/DEV2.1/Exception/ex1/NullPointerException.java
@@ -0,0 +1,6 @@
+public class NullPointerException {
+    public static void main(String[] args) {
+        String str = null;
+        int length = str.length(); // Tentative d'accéder à une méthode sur un objet nul
+    }
+}
diff --git a/DEV2.1/Exception/ex1/NumberFormatException.java b/DEV2.1/Exception/ex1/NumberFormatException.java
new file mode 100644
index 0000000..8206e3b
--- /dev/null
+++ b/DEV2.1/Exception/ex1/NumberFormatException.java
@@ -0,0 +1,6 @@
+public class NumberFormatException {
+    public static void main(String[] args) {
+        String str = "abc";
+        int num = Integer.parseInt(str); // Conversion d'une chaîne non numérique en entier
+    }
+}
diff --git a/DEV2.1/Exception/ex1/RuntimeExceptionExample.java b/DEV2.1/Exception/ex1/RuntimeExceptionExample.java
new file mode 100644
index 0000000..3913436
--- /dev/null
+++ b/DEV2.1/Exception/ex1/RuntimeExceptionExample.java
@@ -0,0 +1,5 @@
+public class RuntimeExceptionExample {
+    public static void main(String[] args) {
+        throw new UnsupportedOperationException("Operation not supported"); // Lancement d'une exception d'opération non supportée
+    }
+}
diff --git a/DEV2.1/Exception/ex2/ArithmeticExceptionExample.java b/DEV2.1/Exception/ex2/ArithmeticExceptionExample.java
new file mode 100644
index 0000000..894b5e1
--- /dev/null
+++ b/DEV2.1/Exception/ex2/ArithmeticExceptionExample.java
@@ -0,0 +1,14 @@
+public class ArithmeticExceptionExample {
+    public static void main(String[] args) {
+        try {
+            computeDivision(); // Appel de la méthode responsable de l'exception
+        } catch (ArithmeticException e) {
+            System.out.println("Une erreur arithmétique s'est produite : " + e.getMessage());
+        }
+    }
+
+    // Méthode responsable de l'exception
+    public static void computeDivision() {
+        int result = 10 / 0; // Division par zéro
+    }
+}
diff --git a/DEV2.1/Exception/ex2/Main.java b/DEV2.1/Exception/ex2/Main.java
new file mode 100644
index 0000000..f968057
--- /dev/null
+++ b/DEV2.1/Exception/ex2/Main.java
@@ -0,0 +1,9 @@
+public class Main {
+    public static void main(String[] args) {
+        try {
+            ArithmeticExceptionVrai.computeDivision();
+        } catch (ArithmeticException e) {
+            System.out.println("Une erreur arithmétique s'est produite : " + e.getMessage());
+        }
+    }
+}
diff --git a/DEV2.1/Exception/ex3/Incomplet.java b/DEV2.1/Exception/ex3/Incomplet.java
new file mode 100644
index 0000000..4c53eef
--- /dev/null
+++ b/DEV2.1/Exception/ex3/Incomplet.java
@@ -0,0 +1,13 @@
+import java.io.IOException;
+
+public class Incomplet {
+    public static void main(String[] args) {
+        byte[] txt = {0x48, 0x65, 0x6C, 0x6C, 0x6F, 0x0D, 0x0A};
+        try {
+            System.out.write(txt);
+            System.out.flush();
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+    }
+}