Object-Oriented Programming (III)-memory analysis during program execution and Object-Oriented Programming

Object-Oriented Programming (III)-memory analysis during program execution and Object-Oriented Programming
Memory analysis (SxtStu. java)

Stack):

Storage: local variables;

 Heap):

Stores new objects;

 Method):

Storage: class information (CODE), static variables, constant pools (string constants), etc.

Stack features: automatic allocation of continuous space, followed by first-in-first-out; generally placed with local variables

Heap features: discontinuous space; placement of newly created objects;

Perform the following analysis:

The memory analysis diagram is as follows:

 

Now we analyze Figure 2:

Student class:

Public class Student {// static data String name; int id; int age; int weight; Computer computer; // Each Student has a Computer // dynamic behavior public void study () {System. out. println (name + "");} public void sayHello (String sname) {System. out. println (name + "" + sname + ", Hello ~ ");}}

Computer Class:

Public class Computer {String brand; // brand int cpuSpeed; // cpu}

Then:

Public class Test2 {public static void main (String [] args) {Student s1 = new Student (); s1.name = "Xiong 'er"; s1.age = 18; computer c = new Computer (); c. brand = "Lenovo"; c. cpuspeed= 100; s1.computer = c; // c. brand = "Dell ";

  System.out.println(s1.computer.brand); } }

The memory analysis is as follows:

Note: If you add the comment section "c. brand =" Dell ";", s1.computer. brand finally outputs "Dell" because they point to the same place.