Java中匿名内部类访问局部变量为什么要声明为final类型啊，可为什么在main()方法中使用匿名内部类与在其他方法中会有不同？
请各位大虾看看下面两个程序：
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
class Logo
{
    private String name;
    private String pass;
    public Logo(String name,String pass)
    {
        this.name=name;
        this.pass=pass;
    }
    public boolean fun(String name,String pass)
    {
        if((this.name.equals("084221019"))&&(this.pass.equals("t1990520123")))return true;
        else return false;
    }
}
public class JFrameDemo08
{
    public static void main(String args[])throws Exception
    {
        JFrame frame=new JFrame("this is a windows");
        JLabel label1=new JLabel("账号");
        JTextField text=new JTextField(10);
        JButton but1=new JButton("登陆");
        JLabel label2=new JLabel("密码");
        JPasswordField password =new JPasswordField(10);
        JButton but2=new JButton("重置");
        JLabel show=new JLabel("请登录");
        frame.setLayout(new FlowLayout());
        frame.add(label1);
        frame.add(text);
        frame.add(but1);
        frame.add(label2);
        frame.add(password);
        frame.add(but2);
        frame.add(show);
        password.setEchoChar('#');
        but1.addActionListener(new ActionListener()
        {
            public void actionPerformed(ActionEvent e)
            {
                if(e.getSource()==but1)
                {
                    String textname=text.getText();
                    String passname=new String(password.getPassword());
                    Logo logo=new Logo(textname,passname);
                    if(logo.fun(textname,passname))
                    {
                        show.setText("登陆成功");
                    }
                    else 
                    {
                        show.setText("账号或密码错误！！！请重新输入");
                    }
                }
            }
        });
        but2.addActionListener(new ActionListener()
        {
            public void actionPerformed(ActionEvent e)
            {
                if(e.getSource()==but2)
                {
                    text.setText("");
                    password.setText("");
                    show.setText("请重新输入账号和密码！！！！");
                }
            }
        });
        frame.addWindowListener(new WindowListener()
        {
            public void windowOpened(WindowEvent e)
            {
            }
            public void windowClosing(WindowEvent e)
            {
                System.out.println("窗口已经关闭");
                System.exit(1);
            }
            public void windowClosed(WindowEvent e)
            {
                System.out.println("窗口被关闭");
            }
            public void windowIconified(WindowEvent e)
            {
                System.out.println("窗口最小化");
            }
            public void windowDeiconified(WindowEvent e)
            {
                System.out.println("窗口从最小化到正常");
            }
            public void windowActivated(WindowEvent e)
            {
            }
            public void windowDeactivated(WindowEvent e)
            {
            }
        });
        frame.pack();
        frame.setVisible(true);
    }
}
上面这个运行会出错，但下面这个就没问题：
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
class Logo
{
    private String name;
    private String pass;
    public Logo(String name,String pass)
    {
        this.name=name;
        this.pass=pass;
    }
    public boolean fun(String name,String pass)
    {
        if((this.name.equals("084221019"))&&(this.pass.equals("t1990520123")))return true;
        else return false;
    }
}
class Performer
{
    private JFrame frame=new JFrame("this is a windows");
    private JLabel label1=new JLabel("账号");
    private JTextField text=new JTextField(10);
    private JButton but1=new JButton("登陆");
    private JLabel label2=new JLabel("密码");
    private JPasswordField password =new JPasswordField(10);
    private JButton but2=new JButton("重置");
    private JLabel show=new JLabel("请登录");
    public Performer()
    {
        frame.setLayout(new FlowLayout());
        frame.add(label1);
        frame.add(text);
        frame.add(but1);
        frame.add(label2);
        frame.add(password);
        frame.add(but2);
        frame.add(show);
        password.setEchoChar('#');
        but1.addActionListener(new ActionListener()
        {
            public void actionPerformed(ActionEvent e)
            {
                if(e.getSource()==but1)
                {
                    String textname=text.getText();
                    String passname=new String(password.getPassword());
                    Logo logo=new Logo(textname,passname);
                    if(logo.fun(textname,passname))
                    {
                        show.setText("登陆成功");
                    }
                    else 
                    {
                        show.setText("账号或密码错误！！！请重新输入");
                    }
                }
            }
        });
        but2.addActionListener(new ActionListener()
        {
            public void actionPerformed(ActionEvent e)
            {
                if(e.getSource()==but2)
                {
                    text.setText("");
                    password.setText("");
                    show.setText("请重新输入账号和密码！！！！");
                }
            }
        });
        frame.addWindowListener(new WindowListener()
        {
            public void windowOpened(WindowEvent e)
            {
            }
            public void windowClosing(WindowEvent e)
            {
                System.out.println("窗口已经关闭");
                System.exit(1);
            }
            public void windowClosed(WindowEvent e)
            {
                System.out.println("窗口被关闭");
            }
            public void windowIconified(WindowEvent e)
            {
                System.out.println("窗口最小化");
            }
            public void windowDeiconified(WindowEvent e)
            {
                System.out.println("窗口从最小化到正常");
            }
            public void windowActivated(WindowEvent e)
            {
            }
            public void windowDeactivated(WindowEvent e)
            {
            }
        });
        frame.pack();
        frame.setVisible(true);
    }
}
public class JFrameDemo08
{
    public static void main(String args[])throws Exception
    {
        new Performer();
    }
}