The life span and lifecycle of spring learning beans

Survival range of 1.bean:

(1) Singleton: Default, Single case

(2) Prototype: Prototypes, non-singleton

(3) Request: In an HTTP request, the container returns the same instance of the bean, and for different requests, a different instance is returned.

(4) Session: The scope of the request becomes session

(5) Gloabsession: Global Session

Request,session is primarily used in the Web

This time we are mainly exploring the 2 survival areas of Singleton and prototype.

<span style= "color: #FF0000;" > If scope is Singleton, the two are equal, and if scope is prototype, the two are not equal. </span>

Instance Code

public class User {}

Configuration file

<?xml version= "1.0" encoding= "UTF-8"? ><beansxmlns= "Http://www.springframework.org/schema/beans" xmlns: Xsi= "Http://www.w3.org/2001/XMLSchema-instance" xmlns:p= "http://www.springframework.org/schema/p" xsi: schemalocation= "Http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/ Spring-beans-3.0.xsd "><bean name=" user "class=" Com.qzp.model.User "scope=" prototype "></bean></ Beans>

Test code

public class Testscope {public static void main (string[] args) {ApplicationContext cxt=new Classpathxmlapplicationcontext ("Applicationcontext.xml"); User u1= (user) Cxt.getbean ("User"); User u2= (user) Cxt.getbean ("User"); System.out.println (U1.hashcode ()); System.out.println (U2.hashcode ()); <span style= "color: #FF0000;" >//If scope is singleton, the two are equal, and if scope is prototype, the two are not equal. </span>system.out.println (U1==U2);}}

Life cycle of 2.bean

(1) Lazy-init: Lazy load, if true, the bean will delay loading, if false, the bean will be loaded immediately, the default is True

(2) Init-method: Initialization method

<bean name= "user" class= "Com.qzp.model.User" lazy-init= "true" init-method= "Init" destroy-method= "destroy" depends-on= "Student" ></bean>

where init-method= "Init" Init is the Init method in the class user

(3) Destory-method: Method of Destruction

(4) Depends-on: Initialization of one bean depends on the initialization of another bean

Instance code:

public class User {private string Username;private string Password;public User () {super ()  ;        System.out.println ("User's construction method ...."); public void init () {         SYSTEM.OUT.PRINTLN ("User initialization method ...");    }&N bsp;    public void Destroy () {         System.out.println ("User's Destruction Method ..."); nbsp;   }public String getusername () {return userName;} public void Setusername (String userName) {this.username = UserName;} Public String GetPassword () {return password;} public void SetPassword (String password) {this.password = password;}} 

public class Student {private String name;private int age;public Student () {super (); System.out.println ("Construction Method of student ..."); Public String GetName () {return name;} public void SetName (String name) {this.name = name;} public int getage () {return age;} public void Setage (int.) {this.age = age;}}

Configuration file

<?xml version= "1.0" encoding= "UTF-8"? ><beans xmlns= "Http://www.springframework.org/schema/beans" xmlns: Xsi= "Http://www.w3.org/2001/XMLSchema-instance" xmlns:p= "http://www.springframework.org/schema/p" xsi: schemalocation= "Http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/ Spring-beans-3.0.xsd "> <bean name=" User "class=" Com.qzp.model.User "lazy-init=" true "init-method=" Init " Destroy-method= "Destroy" depends-on= "student" ></bean> <bean name= "student" class= " Com.qzp.model.Student "></bean></beans>

Test code:

public class Testlifecycle{public static void Main (string[] args) {         Abstractapplicationcontext cxt=new Classpathxmlapplicationcontext ("Applicationcontext.xml");          <span style= "color: #FF0000;" >//If the following code is executed for lazy loading, then the constructor of the class is executed. </span>         Cxt.getbean ("user");          Cxt.close ();}}

The test results are as follows:

The construction method of student ...
User's construction method ....
User Initialization Method ...
User's Destruction Method ...

The life span and lifecycle of spring learning beans