Math类API的用法和字符串转数字

public class JavaApiSimpleDemo {
public static void main(String[] args) {

double num = 3.6;
System.out.println("向上取整：" + Math.ceil(num));
System.out.println("向下取整：" + Math.floor(num));
System.out.println("四舍五入：" + Math.round(num));
System.out.println("随机数(0~1)：" + Math.random());
System.out.println("最大值：" + Math.max(15, 28));

System.out.println("------------------------");

String numStr = "888";
int number = Integer.parseInt(numStr);
System.out.println("字符串转数字：" + number + 1);

}
}