递归求三角数字

package cn.gwssi;import java.io.BufferedReader;import java.io.IOException;import java.io.InputStreamReader;public class TriangleApp {    /**     * @param args     */    static int theNumber;       public static void main(String[] args) throws IOException {        // TODO Auto-generated method stub        System.out.print("Enter a number:");        theNumber=getInt();        int theAnswer=triangle(theNumber);        System.out.println("Triangle="+theAnswer);    }    public static String getString() throws IOException{        InputStreamReader isr = new InputStreamReader(System.in);        BufferedReader br = new BufferedReader(isr);        String s = br.readLine();        return s;    }    public static int triangle(int n){        if(n==1)            return 1;        else            return (n+triangle(n-1));    }    public static int getInt() throws IOException{        String s =getString();        return Integer.parseInt(s);    }}