给出一个字符串或其他，返回一个指定长度的字符串，长度小于指定长度，用指定字符填充

实现代码如下：

 

               public static String createNewStr(Object obj,int max_length,boolean insertFrontflag,String insertStr) {
		return createFactory(max_length,insertFrontflag,String.valueOf(obj).length(),insertStr,String.valueOf(obj));
	}
	public static String createFactory(int max_length,boolean insertFrontflag,int current_length, String insertStr, String current_str) {
		if(current_str.length()>=max_length){
			return current_str;
		}
		if (current_str.length() < max_length) {
			if(insertFrontflag){
			    current_str=insertStr+current_str;
			}else{
				current_str+=insertStr;	
			}
			current_str=createFactory(max_length,insertFrontflag,current_str.length(), insertStr, current_str);
		} else if (current_str.length() == max_length) {
			return current_str;
		}
		return current_str;
	}

	public static void main(String[] args) {
		System.out.println(createNewStr("ffff",100,false,"#"));
	}

 另外String.Format也可实现，详细我的收藏Java里相关