import java.awt.*;
import javax.swing.*;
@SuppressWarnings("serial")
class Calculato extends JFrame {
public Calculato() {
init();
}
public Calculato(String title) {
super(title);
init();
}
private void init() {
JTextField ta = new JTextField(20);
Container cp = this.getContentPane();
cp.setLayout(new BorderLayout());
cp.add(ta, BorderLayout.NORTH);
JPanel p=new JPanel(new GridLayout(4,4));
String st[]={"7","8","9","+","4","5","6","-","1","2","3","*","0",".","/","=",};
// add(new Button("1"));
// add(new Button("2"));
// add(new Button("3"));
// add(new Button("4"));
// add(new Button("5"));
// add(new Button("6"));
JButton j[];
j=new JButton[st.length];
for(int i=0;i<=st.length;i++){
j[i]=new JButton(st[i]);
ta.add(j[i]);
}
getContentPane().add(p,BorderLayout.CENTER);
}
}
public class baseinfo {
public static void main(String[] args) {
JFrame frame = new Calculato("计算器");
Image icon = Toolkit.getDefaultToolkit().getImage(
"D:\\Work\\win\\bin\\6.jpeg");// 改变图标。
frame.setIconImage(icon);
frame.setSize(400, 400);
frame.setLocation(300, 200);// 设置x，y的坐标。
frame.setResizable(false);// 设置窗口不可放大。
frame.setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE);
frame.setVisible(true);
frame.setLocationRelativeTo(null);
}
}
那里有错，求解答 谢谢