package pack;
/*基本数据类型对象包装类
* byte Byte
* short Short
* int Integer
* long Long
* boolean Boolean
* float Float
* double Double
* char Character*/
public class Main {
public static void main(String[] args) {
sys(Integer.MAX_VALUE);
sys(Integer.SIZE);
Integer i = new Integer123); //相当于Integer i = 4;
int a = i.intValue();
String s = Integer.toString(4); //两种方法将整数变为字符串
String s1 = String.valueOf(3);
String s2 = "a";
sys(Integer.parseInt(s1)); //将字符串变为整数
sys(Long.parseLong(s1));
sys(Boolean.parseBoolean("true"));
sys(Character.toUpperCase('a')); //将小写字母转换为大写
sys(Integer.rotateLeft(345,1)); //左移一位,即乘以2