【原】确保输入的字符串是数值

 

 

//B1.java
import java.io.*;

public class B1
{
    public static void main(String[] args){
        String str2 = new A1().check();
        System.out.println(str2);
    }    
}



class A1 {
    private String str1;
    public String check(){
        try
        {             
             char ch;
             BufferedReader buf;
             buf=new BufferedReader(new InputStreamReader(System.in));
             str1 = buf.readLine();                
             for (int i=0;i<str1.length();i++)
             {
                ch=str1.charAt(i);
                 if (!Character.isDigit(ch))               
                  throw new NumberFormatException();  
             }
            
        }catch(IOException e){
            e.printStackTrace();
        }catch(NumberFormatException e){
            System.out.println("输入的参数不是数值类型");
        }
        return str1;
    }    
}