自动装箱、自动拆箱
1.自动装箱
Object obj = 3;
//相当于Object obj = new Integer(3);
System.out.println(obj);
2.自动拆箱
double d = new Double(3.14);
//相当于double d = new Double(3.14).doubleValue();
System.out.println(d);
1.自动装箱
Object obj = 3;
//相当于Object obj = new Integer(3);
System.out.println(obj);
2.自动拆箱
double d = new Double(3.14);
//相当于double d = new Double(3.14).doubleValue();
System.out.println(d);