前言
上一篇文章主要學習了下bean的配置、注入、自定義屬性編輯器，今天來熟悉bean的生命周期。
任何一個事物都有自己的生命周期，生命的開始、生命中、生命結束。大家最熟悉的應該是servlet 的生命周期吧。和 servlet 一樣 spring bean 也有自己的生命周期。
在開發中生命周期是一個很常見的名詞，基本每種編程語言都能找到與它關聯的。關于bean的生命周期我在網上也找了好多，基本都差不多。這里我主要是想通過代碼來驗證，畢竟學的知識都是一樣的，都是學的java，最重要的是動手練習，這樣印象更深。
下面是它生命周期的描述，我們通過demo來進行驗證。
下圖是它執行的順序。
一、創建liftcycle類實現beanfactoryaware,beannameaware,initializingbean,disposablebean,applicationcontextaware5個接口方法
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
|
package cuiyw.spring.service;import org.springframework.beans.beansexception;import org.springframework.beans.factory.beanfactory;import org.springframework.beans.factory.beanfactoryaware;import org.springframework.beans.factory.beannameaware;import org.springframework.beans.factory.disposablebean;import org.springframework.beans.factory.initializingbean;import org.springframework.context.applicationcontext;import org.springframework.context.applicationcontextaware;public class lifecycle implements beanfactoryaware,beannameaware,initializingbean,disposablebean,applicationcontextaware{ private string name; public string getname() { system.out.println("getname name="+name); return name; } public void setname(string name) { system.out.println("setname name="+name); this.name = name; } public void afterpropertiesset() throws exception { // todo auto-generated method stub system.out.println("initializingbean.afterpropertiesset()"); } public void setbeanname(string arg0) { // todo auto-generated method stub system.out.println("beannameaware.setbeanname"); } public void setbeanfactory(beanfactory arg0) throws beansexception { // todo auto-generated method stub system.out.println("beanfactoryaware.setbeanfactory"); } public void destroy() throws exception { // todo auto-generated method stub system.out.println("disposablebean.destroy"); } public void myinit() { system.out.println("【init-method】調用<bean>的init-method屬性指定的初始化方法"); } public void mydestory() { system.out.println("【destroy-method】調用<bean>的destroy-method屬性指定的初始化方法"); } public void setapplicationcontext(applicationcontext arg0) throws beansexception { // todo auto-generated method stub system.out.println("applicationcontextaware.setapplicationcontext"); } } |
二、注冊instantiationawarebeanpostprocessor接口
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
|
package cuiyw.spring.service;import java.beans.propertydescriptor;import org.springframework.beans.beansexception;import org.springframework.beans.propertyvalues;import org.springframework.beans.factory.config.instantiationawarebeanpostprocessor;public class myinstantiationawarebeanpostprocessor implements instantiationawarebeanpostprocessor{ public object postprocessafterinitialization(object bean, string beanname) throws beansexception { // todo auto-generated method stub system.out.println("instantiationawarebeanpostprocessor.postprocessafterinitialization"); return bean; } public object postprocessbeforeinitialization(object bean, string beanname) throws beansexception { // todo auto-generated method stub system.out.println("instantiationawarebeanpostprocessor.postprocessbeforeinitialization"); return bean; } public boolean postprocessafterinstantiation(object bean, string beanname) throws beansexception { // todo auto-generated method stub system.out.println("instantiationawarebeanpostprocessor.postprocessafterinstantiation"); return true; } public object postprocessbeforeinstantiation(class<?> beanclass, string beanname) throws beansexception { // todo auto-generated method stub system.out.println("instantiationawarebeanpostprocessor.postprocessbeforeinstantiation"); return null; } public propertyvalues postprocesspropertyvalues(propertyvalues pvs, propertydescriptor[] pds, object bean, string beanname) throws beansexception { // todo auto-generated method stub system.out.println("instantiationawarebeanpostprocessor.postprocesspropertyvalues"); return pvs; }} |
三、注冊beanpostprocessor接口
其實instantiationawarebeanpostprocessor繼承beanpostprocessor，所以在上面我也實現了beanpostprocessor接口的方法
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
|
package cuiyw.spring.service;import org.springframework.beans.beansexception;import org.springframework.beans.factory.config.beanpostprocessor;public class mybeanpostprocessor implements beanpostprocessor { public object postprocessafterinitialization(object bean, string beanname) throws beansexception { // todo auto-generated method stub system.out.println("beanpostprocessor.postprocessafterinitialization "); return bean; } public object postprocessbeforeinitialization(object bean, string beanname) throws beansexception { // todo auto-generated method stub system.out.println("beanpostprocessor.postprocessbeforeinitialization"); return bean; }} |
四、注冊beanfactorypostprocessor接口
|
1
2
3
4
5
6
7
8
9
10
|
package cuiyw.spring.service;import org.springframework.beans.beansexception;import org.springframework.beans.factory.config.beanfactorypostprocessor;import org.springframework.beans.factory.config.configurablelistablebeanfactory;public class mybeanfactorypostprocessor implements beanfactorypostprocessor { public void postprocessbeanfactory(configurablelistablebeanfactory arg0) throws beansexception { // todo auto-generated method stub system.out.println("beanfactorypostprocessor.postprocessbeanfactory"); }} |
五、在上下文中配置
這里還是在上一個博客demo的基礎上進行修改，為了有其他干擾，我先把service去掉了。
|
1
2
3
4
5
6
7
8
9
10
11
|
<?xml version="1.0" encoding="utf-8"?><beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/xmlschema-instance" xsi:schemalocation="http://www.springframework.org/schema/beanshttp://www.springframework.org/schema/beans/spring-beans.xsd"><bean id="beanpostprocessor" class="cuiyw.spring.service.mybeanpostprocessor"></bean><bean id="instantiationawarebeanpostprocessor" class="cuiyw.spring.service.myinstantiationawarebeanpostprocessor"></bean><bean id="beanfactorypostprocessor" class="cuiyw.spring.service.mybeanfactorypostprocessor"></bean><bean id="lifecycle" class="cuiyw.spring.service.lifecycle" init-method="myinit" destroy-method="mydestory"><property name="name" value="cuiyw1"></property></bean></beans> |
六、在main中使用bean
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
|
package cuiyw.springaop;import org.springframework.beans.factory.beanfactory;import org.springframework.context.applicationcontext;import org.springframework.context.support.classpathxmlapplicationcontext;import cuiyw.spring.iservice.iservice;import cuiyw.spring.service.lifecycle;public class app { public static void main( string[] args ) { applicationcontext context=new classpathxmlapplicationcontext(new string[]{"applicationcontext.xml"}); beanfactory factory=context; lifecycle lifecycle=factory.getbean("lifecycle",lifecycle.class); lifecycle.setname("cuiyw2"); system.out.println("lifecycle.name="+lifecycle.getname()); ((classpathxmlapplicationcontext)factory).registershutdownhook(); /*service=(iservice)factory.getbean("servicea"); service.service("cuiyw servicea"); service=(iservice)factory.getbean("serviceimpl"); service.service("cuiyw serviceimpl"); */ }} |
七、輸入打印結果
可以發現輸出的順序和上面圖的順序基本一致。
總結
以上就是這篇文章的全部內容了，希望本文的內容對大家的學習或者工作具有一定的參考學習價值，如果有疑問大家可以留言交流，謝謝大家對服務器之家的支持。
原文鏈接：http://www.cnblogs.com/5ishare/p/8030038.html
