java in the int vs Integer

int vs Integer

• Default basic type int is 0; package type corresponding to the default null value Integer

• Integer object will take up more memory. Integer is an object, the object needs to store metadata. But int is a primitive type of data, so take up less space

• Autoboxing: converting the basic data types to the corresponding type of packaging

• Automatic unboxing: converting to the corresponding type of packaging of the basic data types

// 自动装箱
Integer integer =100;
// 自动拆箱
int i = interger;   

**IntegerCache**整型对象在内部实现中通过使用相同的对象引用实现了缓存和重用,用来节省内存和提高性能
Integer i = 100;
Integer j = 100;
System.out.print(i == j); //true

Integer i = 128;
Integer j = 128;
System.out.print(i == j); //false

On the int and Integer

The difference between int and Integer: speaking of JAVA interview 504

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