import java.rmi.*;
import java.awt.*;
import java.awt.event.*;
import java.io.*;
import javax.swing.*;

public class SClientsr extends JFrame 
{       
        TextField t1=new TextField(20);
        Label rs=new Label("0");
        JButton b=new JButton("ANS :");
       Panel f=new Panel(new GridLayout(2,2));

        SInterface i;

   public SClientsr()
    {
         super("Client Side");
         setSize(250, 250);
         setLocation(300, 300); 
         getContentPane().add(f,"NORTH");
        f.add("Summation limit");
        f.add(t1);
        f.add(b);
        f.add(rs);
        f.pack();
    }

 b.addActionListener(new ActionListener() {
  public void actionPerformed(ActionEvent evt) {
      int n=Integer.parseInt(t1.getText());
            try
            {
                int m=i.summation(n);
                rs.setText(m);
            }
                catch (Exception epx){}
        }
    });
}

    public class SClient
    {
    public static void main(String args[])
        {
         SClientsr sc=new SClientsr();
         sc.setDefaultCloseOperation(EXIT_ON_CLOSE);
         sc.setVisible(true);
        }
    }

I am getting the following errors:

C:\tjm>javac SClient.java
SClient.java:29: error: <identifier> expected
 b.addActionListener(new ActionListener() {
                    ^
SClient.java:29: error: illegal start of type
 b.addActionListener(new ActionListener() {
                     ^
SClient.java:29: error: ')' expected
 b.addActionListener(new ActionListener() {
                        ^
SClient.java:29: error: ';' expected
 b.addActionListener(new ActionListener() {
                                       ^
SClient.java:29: error: illegal start of type
 b.addActionListener(new ActionListener() {
                                        ^
SClient.java:29: error: <identifier> expected
 b.addActionListener(new ActionListener() {
                                         ^
SClient.java:29: error: ';' expected
 b.addActionListener(new ActionListener() {
                                           ^
SClient.java:39: error: class, interface, or enum expected
        });
         ^
SClient.java:40: error: class, interface, or enum expected
}
^
9 errors

PLEASE HELP