[java] bouton equal marche pas

package Calcul;
public class Main 
{
    public static void main(String[] args) 
    {
        Calculatrice calculette=new Calculatrice();
    }
}
 
package Calcul;
import java.awt.Color ;
import java.awt.Dimension; 
import java.awt.Font; 
import java.awt.event.ActionListener ;
import java.awt.event.ActionEvent;
import java.awt.BorderLayout; 
import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
 
public class Calculatrice extends JFrame 
{
 private JPanel container=new JPanel();
 String[]tab_string={"1","2","3","4","5","6","7","8","9","0",".","=","C","+","-","*","/"};
 JButton[]tab_button=new JButton[tab_string.length];
 
 private JLabel ecran=new JLabel();
 private Dimension dim=new Dimension(50,40);
 private Dimension dim2=new Dimension(50,31);
 private double chiffre1 ;
 private boolean clicOperateur=false,update=false;
 private String operateur="";
 
 public Calculatrice()
 {
	 this.setSize(240,260) ;
	 this.setTitle("Calculette") ;
	 this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE) ;
	 this.setLocationRelativeTo(null) ;
	 this.setResizable(false) ;
	 initComposant();
 
	 this.setContentPane(container) ;
	 this.setVisible(true) ;
 }
 
 private void initComposant()
 {
	 Font police=new Font("Arial",Font.BOLD,20);
	 ecran=new JLabel("0");
	 ecran.setFont(police);
	 ecran.setHorizontalAlignment(JLabel.RIGHT);
	 ecran.setPreferredSize(new Dimension(220,20));
 
	 JPanel operateur=new JPanel();
	 operateur.setPreferredSize(new Dimension(55,225));
	 JPanel chiffre=new JPanel();
	 chiffre.setPreferredSize(new Dimension(165,225));
	 JPanel panEcran=new JPanel();
	 panEcran.setPreferredSize(new Dimension(220,30));
 
	 for(int i=0;i<tab_string.length;i++)
	 {
		tab_button[i]=new JButton(tab_string[i]);
		tab_button[i].setPreferredSize(dim);
 
		switch(i)
		{
		  case 11:
			  tab_button[i].setForeground(Color.red);
			  tab_button[i].addActionListener(new ResetListener());
			  chiffre.add(tab_button[i]);
			  break;
		  case 12:
			  tab_button[i].addActionListener(new EgalListener());
			  operateur.add(tab_button[i]);
			  break;
		  case 13:
			  tab_button[i].addActionListener(new PlusListener());
			  tab_button[i].setPreferredSize(dim2);
			  operateur.add(tab_button[i]);
			  break;
		  case 14:
			  tab_button[i].addActionListener(new MoinsListener());
			  tab_button[i].setPreferredSize(dim2);
			  operateur.add(tab_button[i]);
			  break;
		  case 15:
			  tab_button[i].addActionListener(new MultiListener());
			  tab_button[i].setPreferredSize(dim2);
			  operateur.add(tab_button[i]);
			  break;
 
		  case 16:
			  tab_button[i].addActionListener(new DivListener());
			  tab_button[i].setPreferredSize(dim2);
			  operateur.add(tab_button[i]);
			  break;
		  default:
			  chiffre.add(tab_button[i]);
			  tab_button[i].addActionListener(new ChiffreListener());
			  break;
		}
	 }
 
 
	 panEcran.add(ecran);
	 panEcran.setBorder(BorderFactory.createLineBorder(Color.black));
	 container.add(panEcran,BorderLayout.NORTH);
	 container.add(chiffre,BorderLayout.CENTER);
	 container.add(operateur,BorderLayout.EAST);
 }
 private void calcul()
 {
	 if(operateur.equals("+"))
	 {
		 chiffre1=chiffre1+Double.valueOf(ecran.getText()).doubleValue();
		 ecran.setText(String.valueOf(chiffre1));
	 }
	 if(operateur.equals("-"))
	 {
		 chiffre1=chiffre1-Double.valueOf(ecran.getText()).doubleValue();
		 ecran.setText(String.valueOf(chiffre1));
	 }
	 if(operateur.equals("*"))
	 {
		 chiffre1=chiffre1*Double.valueOf(ecran.getText()).doubleValue();
		 ecran.setText(String.valueOf(chiffre1));
	 }
	 if(operateur.equals("/"))
	 {
		 try
		 {
		  chiffre1=chiffre1/Double.valueOf(ecran.getText()).doubleValue();
		  ecran.setText(String.valueOf(chiffre1));
	     }
	     catch(ArithmeticException e)
	     {
	      ecran.setText("0"); 
	     }
	 }	 
  }
  class ChiffreListener implements ActionListener
  {
	@Override
	public void actionPerformed(ActionEvent e) 
	{
		// on affiche le chiffre en plus dans le label
		String str=((JButton)e.getSource()).getText();
		if(update)
		{
			update=false;
		}
		else
		{
			if(!ecran.getText().equals("0")) str=ecran.getText()+str;
		}
		ecran.setText(str);		
	}
  }
//Listener affecté au bouton=
  class EgalListener implements ActionListener
  {
	  @Override
	  public void actionPerformed(ActionEvent arg0)
	  {
		calcul();
	    update=true;
		clicOperateur=false;	  
	  }
  }
  class PlusListener implements ActionListener
  {
	  @Override
	  public void actionPerformed(ActionEvent arg0)
	  {
		  if(clicOperateur)
		  {
			  calcul();
			  ecran.setText(String.valueOf(chiffre1));
		  }
		  else
		  {
			  chiffre1=Double.valueOf(ecran.getText()).doubleValue();
			  clicOperateur=true;
		  }
		  operateur="+";
		  update=true;
	  }
  }
  class MoinsListener implements ActionListener
  {
	  @Override
	  public void actionPerformed(ActionEvent arg0)
	  {
		  if(clicOperateur)
		  {
			  calcul();
			  ecran.setText(String.valueOf(chiffre1));
		  }
		  else
		  {
			  chiffre1=Double.valueOf(ecran.getText()).doubleValue();
			  clicOperateur=true;
		  }
		  operateur="-";
		  update=true;
	  }
  }
 
 
 
 
  class MultiListener implements ActionListener
  {
	  @Override
	  public void actionPerformed(ActionEvent arg0)
	  {
		  if(clicOperateur)
		  {
			  calcul();
			  ecran.setText(String.valueOf(chiffre1));
		  }
 
 
		  else
		  {
			  chiffre1=Double.valueOf(ecran.getText()).doubleValue();
			  clicOperateur=true;
		  }
		  operateur="*";
		  update=true;
	  }
  }
  class DivListener implements ActionListener
  {
	  @Override
	  public void actionPerformed(ActionEvent arg0)
	  {
		  if(clicOperateur)
		  {
			  calcul();
			  ecran.setText(String.valueOf(chiffre1));
		  }
		  else
		  {
			  chiffre1=Double.valueOf(ecran.getText()).doubleValue();
			  clicOperateur=true;
		  }
		  operateur="/";
		  update=true;
	  }
  }
  class ResetListener implements ActionListener
  {
	  @Override
	  public void actionPerformed(ActionEvent arg0)
	  {
		  clicOperateur=false;
		  update=true;
		  chiffre1=0;
		  operateur="";
		  ecran.setText("");		  
	  }
  }
}