java工具類之驗證碼工具類

生成驗證碼之工具類

package cn.edu.dcxy;

import java.util.Random;

public class ItUtil {

    /**
     * 由於工具類無需創建對象，所以把其構造器私有化
     */
    private ItUtil(){

    }
    public static String createVerifyCode(int n) {
        String code = "";
        String data = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
        Random r = new Random();
        for (int i = 0; i < n; i++) {
            int index = r.nextInt(data.length());
            code += data.charAt(index);
        }
        return code;
    }
}