下面程序的目的是在屏幕上显示当前目录下的文件信息。文件信息通过表格JTable的实例显示。请改正程序中的错误(有下划线的语句)，使程序能输出正确的结果。

注意：不改动程序的结构，不得增行或删行。

import java.awt.*;

import javax.swing.*;

import java.util. Date;

import javax.swing.table.*;

import java.applet.*;

import java.io.*;

public class Example3_10 extends JApplet, JFrame

{

public void init()

{

FileModel fm = new FileModel();

JTable jt = new JTable();

jt.setAutoResizeMode(JTable.AUTO_RESIZE_OFF);

jt.setColumnSelectionAllowed(true);

JScrollPane jsp = new JScrollPane(jt);

getContentPane().add(jsp, BorderLayout.CENTER);

}

public static void main(String args[])

{

Example3_10 ft = new Example3_10();

ft.init();

JFrame. f = new JFrame();

f.setDefaultCloseOperation(JFrame.EXIT ON CLOSE);

f.getContentPane() .add(ft.getContentPane());

f.setSize (300, 400);

f.show();

}

}

class FileModel extends AbstractTableModel

{

String[] columnName = new String[] {

"文件名", "大小", "最后修改时间"

}

Object[] [] data;

public FileModel() { this("."); }

public FileModel(String dir)

{

File file = new File(dir);

String files[] = file.list();

data = new Object [files.length] [columnName.length];

for (int i=0; i ＜ files.length; i++)

{

File tmp = new File (files[i]);

data[i] [0] = tmp.getName();

data[i] [1] = new Long(tmp.length());

data[i] [2] = new Date(tmp.lastModified() );

}

}

public int getColumnNumber()

{

return columnName.length;

}

public int getRowCount()

{

return data. length;

}

public String getColumnName(int col)

{

return columnName[col];

}

public Object getValueAt(int row, int col)

{

return data[row] [col];

}

public Class getColumnClass(int c)

{

return getValueAt (0, c) .getClass();

}

}