Spring Bean的性命周期具體引見。本站提示廣大學習愛好者:(Spring Bean的性命周期具體引見)文章只能為提供參考,不一定能成為您想要的結果。以下是Spring Bean的性命周期具體引見正文
Spring作為以後Java最風行、最壯大的輕量級框架,遭到了法式員的熱鬧迎接。精確的懂得Spring Bean的性命周期長短常需要的。我們平日應用ApplicationContext作為Spring容器。這裡,我們講的也是 ApplicationContext中Bean的性命周期。而現實上BeanFactory也是差不多的,只不外處置器須要手動注冊。
1、性命周期流程圖:
Spring Bean的完全性命周期從創立Spring容器開端,直到終究Spring容器燒毀Bean,這個中包括了一系列症結點。
若容器注冊了以上各類接口,法式那末將會依照以上的流程停止。上面將細心講授各接口感化。
2、各類接口辦法分類
Bean的完全性命周期閱歷了各類辦法挪用,這些辦法可以劃分為以下幾類:
1、Bean本身的辦法 : 這個包含了Bean自己挪用的辦法和經由過程設置裝備擺設文件中<bean>的init-method和destroy-method指定的辦法
2、Bean級性命周期接口辦法 : 這個包含了BeanNameAware、BeanFactoryAware、InitializingBean和DiposableBean這些接口的辦法
3、容器級性命周期接口辦法 : 這個包含了InstantiationAwareBeanPostProcessor 和 BeanPostProcessor 這兩個接話柄現,普通稱它們的完成類為“後處置器”。
4、工場後處置器接口辦法 : 這個包含了AspectJWeavingEnabler, ConfigurationClassPostProcessor, CustomAutowireConfigurer等等異常有效的工場後處置器 接口的辦法。工場後處置器也是容器級的。在運用高低文拆卸設置裝備擺設文件以後立刻挪用。
3、演示
我們用一個簡略的Spring Bean來演示一下Spring Bean的性命周期。
1、起首是一個簡略的Spring Bean,挪用Bean本身的辦法和Bean級性命周期接口辦法,為了便利演示,它完成了BeanNameAware、BeanFactoryAware、InitializingBean和DiposableBean這4個接口,同時有2個辦法,對應設置裝備擺設文件中<bean>的init-method和destroy-method。以下:
package springBeanTest;
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;
/**
* @author qsk
*/
public class Person implements BeanFactoryAware, BeanNameAware,
InitializingBean, DisposableBean {
private String name;
private String address;
private int phone;
private BeanFactory beanFactory;
private String beanName;
public Person() {
System.out.println("【結構器】挪用Person的結構器實例化");
}
public String getName() {
return name;
}
public void setName(String name) {
System.out.println("【注入屬性】注入屬性name");
this.name = name;
}
public String getAddress() {
return address;
}
public void setAddress(String address) {
System.out.println("【注入屬性】注入屬性address");
this.address = address;
}
public int getPhone() {
return phone;
}
public void setPhone(int phone) {
System.out.println("【注入屬性】注入屬性phone");
this.phone = phone;
}
@Override
public String toString() {
return "Person [address=" + address + ", name=" + name + ", phone="
+ phone + "]";
}
// 這是BeanFactoryAware接口辦法
@Override
public void setBeanFactory(BeanFactory arg0) throws BeansException {
System.out
.println("【BeanFactoryAware接口】挪用BeanFactoryAware.setBeanFactory()");
this.beanFactory = arg0;
}
// 這是BeanNameAware接口辦法
@Override
public void setBeanName(String arg0) {
System.out.println("【BeanNameAware接口】挪用BeanNameAware.setBeanName()");
this.beanName = arg0;
}
// 這是InitializingBean接口辦法
@Override
public void afterPropertiesSet() throws Exception {
System.out
.println("【InitializingBean接口】挪用InitializingBean.afterPropertiesSet()");
}
// 這是DiposibleBean接口辦法
@Override
public void destroy() throws Exception {
System.out.println("【DiposibleBean接口】挪用DiposibleBean.destory()");
}
// 經由過程<bean>的init-method屬性指定的初始化辦法
public void myInit() {
System.out.println("【init-method】挪用<bean>的init-method屬性指定的初始化辦法");
}
// 經由過程<bean>的destroy-method屬性指定的初始化辦法
public void myDestory() {
System.out.println("【destroy-method】挪用<bean>的destroy-method屬性指定的初始化辦法");
}
}
2、接上去是演示BeanPostProcessor接口的辦法,以下:
package springBeanTest;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.config.BeanPostProcessor;
public class MyBeanPostProcessor implements BeanPostProcessor {
public MyBeanPostProcessor() {
super();
System.out.println("這是BeanPostProcessor完成類結構器!!");
// TODO Auto-generated constructor stub
}
@Override
public Object postProcessAfterInitialization(Object arg0, String arg1)
throws BeansException {
System.out
.println("BeanPostProcessor接口辦法postProcessAfterInitialization對屬性停止更改!");
return arg0;
}
@Override
public Object postProcessBeforeInitialization(Object arg0, String arg1)
throws BeansException {
System.out
.println("BeanPostProcessor接口辦法postProcessBeforeInitialization對屬性停止更改!");
return arg0;
}
}
如上,BeanPostProcessor接口包含2個辦法postProcessAfterInitialization和postProcessBeforeInitialization,這兩個辦法的第一個參數都是要處置的Bean對象,第二個參數都是Bean的name。前往值也都是要處置的Bean對象。這裡要留意。
3、InstantiationAwareBeanPostProcessor 接口實質是BeanPostProcessor的子接口,普通我們繼續Spring為其供給的適配器類InstantiationAwareBeanPostProcessor Adapter來應用它,以下:
package springBeanTest;
import java.beans.PropertyDescriptor;
import org.springframework.beans.BeansException;
import org.springframework.beans.PropertyValues;
import org.springframework.beans.factory.config.InstantiationAwareBeanPostProcessorAdapter;
public class MyInstantiationAwareBeanPostProcessor extends
InstantiationAwareBeanPostProcessorAdapter {
public MyInstantiationAwareBeanPostProcessor() {
super();
System.out
.println("這是InstantiationAwareBeanPostProcessorAdapter完成類結構器!!");
}
// 接口辦法、實例化Bean之前挪用
@Override
public Object postProcessBeforeInstantiation(Class beanClass,
String beanName) throws BeansException {
System.out
.println("InstantiationAwareBeanPostProcessor挪用postProcessBeforeInstantiation辦法");
return null;
}
// 接口辦法、實例化Bean以後挪用
@Override
public Object postProcessAfterInitialization(Object bean, String beanName)
throws BeansException {
System.out
.println("InstantiationAwareBeanPostProcessor挪用postProcessAfterInitialization辦法");
return bean;
}
// 接口辦法、設置某個屬性時挪用
@Override
public PropertyValues postProcessPropertyValues(PropertyValues pvs,
PropertyDescriptor[] pds, Object bean, String beanName)
throws BeansException {
System.out
.println("InstantiationAwareBeanPostProcessor挪用postProcessPropertyValues辦法");
return pvs;
}
}
這個有3個辦法,個中第二個辦法postProcessAfterInitialization就是重寫了BeanPostProcessor的辦法。第三個辦法postProcessPropertyValues用來操作屬性,前往值也應當是PropertyValues對象。
4、演示工場後處置器接口辦法,以下:
package springBeanTest;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.config.BeanDefinition;
import org.springframework.beans.factory.config.BeanFactoryPostProcessor;
import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
public class MyBeanFactoryPostProcessor implements BeanFactoryPostProcessor {
public MyBeanFactoryPostProcessor() {
super();
System.out.println("這是BeanFactoryPostProcessor完成類結構器!!");
}
@Override
public void postProcessBeanFactory(ConfigurableListableBeanFactory arg0)
throws BeansException {
System.out
.println("BeanFactoryPostProcessor挪用postProcessBeanFactory辦法");
BeanDefinition bd = arg0.getBeanDefinition("person");
bd.getPropertyValues().addPropertyValue("phone", "110");
}
}
5、設置裝備擺設文件以下beans.xml,很簡略,應用ApplicationContext,處置器不消手動注冊:
<?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"
xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx"
xsi:schemaLocation="
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.2.xsd">
<bean id="beanPostProcessor" class="springBeanTest.MyBeanPostProcessor">
</bean>
<bean id="instantiationAwareBeanPostProcessor" class="springBeanTest.MyInstantiationAwareBeanPostProcessor">
</bean>
<bean id="beanFactoryPostProcessor" class="springBeanTest.MyBeanFactoryPostProcessor">
</bean>
<bean id="person" class="springBeanTest.Person" init-method="myInit"
destroy-method="myDestory" scope="singleton" p:name="張三" p:address="廣州"
p:phone="15900000000" />
</beans>
6、上面測試一下:
package springBeanTest;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
public class BeanLifeCycle {
public static void main(String[] args) {
System.out.println("如今開端初始化容器");
ApplicationContext factory = new ClassPathXmlApplicationContext("springBeanTest/beans.xml");
System.out.println("容器初始化勝利");
//獲得Preson,並應用
Person person = factory.getBean("person",Person.class);
System.out.println(person);
System.out.println("如今開端封閉容器!");
((ClassPathXmlApplicationContext)factory).registerShutdownHook();
}
}
封閉容器應用的是現實是AbstractApplicationContext的鉤子辦法。
我們來看一下成果:
如今開端初始化容器 2014-5-18 15:46:20 org.springframework.context.support.AbstractApplicationContext prepareRefresh 信息: Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@19a0c7c: startup date [Sun May 18 15:46:20 CST 2014]; root of context hierarchy 2014-5-18 15:46:20 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions 信息: Loading XML bean definitions from class path resource [springBeanTest/beans.xml] 這是BeanFactoryPostProcessor完成類結構器!! BeanFactoryPostProcessor挪用postProcessBeanFactory辦法 這是BeanPostProcessor完成類結構器!! 這是InstantiationAwareBeanPostProcessorAdapter完成類結構器!! 2014-5-18 15:46:20 org.springframework.beans.factory.support.DefaultListableBeanFactory preInstantiateSingletons 信息: Pre-instantiating singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@9934d4: defining beans [beanPostProcessor,instantiationAwareBeanPostProcessor,beanFactoryPostProcessor,person]; root of factory hierarchy InstantiationAwareBeanPostProcessor挪用postProcessBeforeInstantiation辦法 【結構器】挪用Person的結構器實例化 InstantiationAwareBeanPostProcessor挪用postProcessPropertyValues辦法 【注入屬性】注入屬性address 【注入屬性】注入屬性name 【注入屬性】注入屬性phone 【BeanNameAware接口】挪用BeanNameAware.setBeanName() 【BeanFactoryAware接口】挪用BeanFactoryAware.setBeanFactory() BeanPostProcessor接口辦法postProcessBeforeInitialization對屬性停止更改! 【InitializingBean接口】挪用InitializingBean.afterPropertiesSet() 【init-method】挪用<bean>的init-method屬性指定的初始化辦法 BeanPostProcessor接口辦法postProcessAfterInitialization對屬性停止更改! InstantiationAwareBeanPostProcessor挪用postProcessAfterInitialization辦法 容器初始化勝利 Person [address=廣州, name=張三, phone=110] 如今開端封閉容器! 【DiposibleBean接口】挪用DiposibleBean.destory() 【destroy-method】挪用<bean>的destroy-method屬性指定的初始化辦法
以上就是對Java Spring Bean 性命周期的材料整頓,後續持續彌補相干材料,感謝年夜家對本站的支撐!