display.java

来自「把十进制转化了二进制」· Java 代码 · 共 23 行

package binary;
import javax.swing.*;
public class Display {
    public Display() {  
    }
    public int get(){
        while(true){
            String inputString = JOptionPane.showInputDialog(null,"please enter a valid number");
            try{
                int number = Integer.parseInt(inputString);
                if(number<0){
                    throw new Exception("number must be a positive number!");
                }
                return number;
            }catch(NumberFormatException e){
                JOptionPane.showMessageDialog(null,"invalid number");
            }catch(Exception e){
                JOptionPane.showMessageDialog(null,"Error:"+e.getMessage());
            }
        }
    }
}