java 对数字输出格式规范的函数 DecimalFormat

import java.text.DecimalFormat;
public class look {
public static void main(String[] args) {
DecimalFormat format = new DecimalFormat("000");// 定义一种输出格式为000
int department = 7;// 部门编号7
int employee = 3;// 员工编号3
System.out.println(format.format(department) + format.format(employee));
}
}

输出结果：007003