BeanFactoryPostProcessor类的运用

package com.spring.ch04;

import org.springframework.beans.factory.config.BeanFactoryPostProcessor;
import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
import org.springframework.beans.factory.xml.XmlBeanFactory;
import org.springframework.core.io.ClassPathResource;

public class PropertyConfigurerDemo {
	public static void main(String[] args) {
		ConfigurableListableBeanFactory bf=new XmlBeanFactory(new ClassPathResource("/META-INF/postprocessor.xml"));				
		BeanFactoryPostProcessor bfpp=(BeanFactoryPostProcessor)bf.getBean("bfpp");
		bfpp.postProcessBeanFactory(bf);
		System.out.println(bf.getBean("simpleBean"));
		
	}

}

 

BeanFactory配置文件：postprocessor.xml

 

<?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/beans 
 http://www.springframework.org/schema/beans/spring-beans.xsd
">
<!-- 利用PropertyPlaceholderConfigurer回调处理器将替换从已配置的属性文件中加载属性的值，
 只要值符合某种格式规则，默认情况下是${property-name}，就会发生替换。
-->
	<bean id="bfpp" class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
	<property name="location" value="classpath:/META-INF/bfpp.properties"></property>
	
	</bean>
   <bean id="simpleBean" class="com.spring.ch04.SimplePostProcessor">
   <property name="connectionString" value="${simpleBean.connectionString}"/>
   <property name="password" value="${simpleBean.password}"/>
   <property name="username" value="${simpleBean.username}"/>
   
   </bean>
   
 </beans>

 

SimplePostProcessor .java

package com.spring.ch04;

public class SimplePostProcessor {
	private String connectionString;
	private String password;

	private String username;
	public void setConnectionString(String connectionString) {
		this.connectionString = connectionString;
	}
	public void setPassword(String password) {
		this.password = password;
	}
	public void setUsername(String username) {
		this.username = username;
	}
	public String toString(){
		StringBuilder sb=new StringBuilder();
		sb.append("SimplePostProcessor{connectionString=").append(this.connectionString);
		sb.append(",username=").append(this.username).append(",password=").append(this.password);
		return sb.toString();
	}
	

}

 bfpp.properties

simpleBean.connectionString=Hello
simpleBean.password=imaginecup
simpleBean.username=qiaoyanhui

 

 

实现一个BeanFactoryPostProcessor,实现一个简单的回调处理器，它能去除潜在的"流氓"属性值，例如bean定义中留下bollocks这样的字眼。

配置文件：BeanFactory.xml

<?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/beans 
 http://www.springframework.org/schema/beans/spring-beans.xsd
">
<bean id="bfpp" class="com.spring.ch04.ObscenityRemovingBeanFactoryPostProcessor">
	<property name="obscenties">
		<set>
			<value>bollocks</value>
			<value>winky</value>
			<value>bum</value>
			<value>Microsoft</value>
		</set>
	</property>

</bean>
<bean id="simpleBean" class="com.spring.ch04.SimplePostProcessor">
	<property name="connectionString" value="bollocks"/>
	<property name="password" value="imaginecup"/>
	<property name="username" value="Microsoft"/>

</bean>
   
 </beans>

 ObscenityRemovingBeanFactoryPostProcessor.java

package com.spring.ch04;

import java.util.*;

import org.springframework.beans.BeansException;
import org.springframework.beans.factory.config.BeanDefinition;
import org.springframework.beans.factory.config.BeanDefinitionVisitor;
import org.springframework.beans.factory.config.BeanFactoryPostProcessor;
import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
import org.springframework.util.StringValueResolver;

public class ObscenityRemovingBeanFactoryPostProcessor implements
		BeanFactoryPostProcessor {
	private Set<String> obscenties;
	public ObscenityRemovingBeanFactoryPostProcessor(){
		this.obscenties=new HashSet<String>();
	}
	public void postProcessBeanFactory(
			ConfigurableListableBeanFactory beanFactory) throws BeansException {
		String[] beanNames=beanFactory.getBeanDefinitionNames();
		for(String beanName:beanNames){
			BeanDefinition bd=beanFactory.getBeanDefinition(beanName);
			StringValueResolver valueResover=new StringValueResolver() {
				public String resolveStringValue(String strVal) {
					if(isObscene(strVal)) return "*****";
					return strVal;
				}
			};
			BeanDefinitionVisitor visitor=new BeanDefinitionVisitor(valueResover);
			visitor.visitBeanDefinition(bd);
		}
	}
	public boolean isObscene(Object value){
		String potentialObscenity=value.toString().toUpperCase();
		return this.obscenties.contains(potentialObscenity);
	}
	public void setObscenties(Set<String> obscenties) {
		this.obscenties.clear();
		for(String obscenity:obscenties){
			this.obscenties.add(obscenity.toUpperCase());
		}
	}

}

 执行类：

package com.spring.ch04;

import org.springframework.beans.factory.config.BeanFactoryPostProcessor;
import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
import org.springframework.beans.factory.xml.XmlBeanFactory;
import org.springframework.core.io.ClassPathResource;

public class PropertyConfigurerDemo {
	public static void main(String[] args) {

		ConfigurableListableBeanFactory bf=new XmlBeanFactory(new ClassPathResource("/META-INF/BeanFactory.xml"));

		
		BeanFactoryPostProcessor bfpp=(BeanFactoryPostProcessor)bf.getBean("bfpp");
		bfpp.postProcessBeanFactory(bf);
		System.out.println(bf.getBean("simpleBean"));
		
	}

}

 

输出结果：

SimplePostProcessor{connectionString=*****,username=*****,password=imaginecup

 

 ObscenityRemovingBeanFactoryPostProcessor.java的改进类

 ObscenityRemovingBeanFactoryPostProcessor1.java

package com.spring.ch04;
import java.util.*;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.BeanNameAware;
import org.springframework.beans.factory.config.BeanDefinition;
import org.springframework.beans.factory.config.BeanDefinitionVisitor;
import org.springframework.beans.factory.config.BeanFactoryPostProcessor;
import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
import org.springframework.util.StringValueResolver;

public class ObscenityRemovingBeanFactoryPostProcessor1 implements
		BeanFactoryPostProcessor, BeanNameAware {
	private Set<String> obscenities;
	public ObscenityRemovingBeanFactoryPostProcessor1(){
		this.obscenities=new HashSet<String>();
		this.obscenitiesRemoved=new HashSet<String>();
	}
	public void setObscenities(Set<String> obscenities) {
		this.obscenities.clear();
		for(String obscenity :obscenities){
			this.obscenities.add(obscenity.toUpperCase());
		}
	}
	private Set<String> obscenitiesRemoved;
	private String name;
	@Override
	public void postProcessBeanFactory(
			ConfigurableListableBeanFactory beanFactory) throws BeansException {
		String[] beanNames=beanFactory.getBeanDefinitionNames();
		for(String beanName:beanNames){
			//核查我们有没有为该bean修改BeanDefinition
			if(beanName.equals(this.name)) {
				continue;
			}
			
			BeanDefinition bd=beanFactory.getBeanDefinition(beanName);
			StringValueResolver valueResolver=new StringValueResolver(){
				@Override
				public String resolveStringValue(String strVal) {
					if(isObscene(strVal)) {
						obscenitiesRemoved.add(strVal);
						return "******";
					}
					return strVal;
				}
			};
			BeanDefinitionVisitor visitor=new BeanDefinitionVisitor(valueResolver);
			visitor.visitBeanDefinition(bd);
		}
		//将一个集合注册名 为obscenitiesRemoved的单例bean
		beanFactory.registerSingleton("obscenitiesRemoved", this.obscenitiesRemoved);
		//打印被过滤的属性值
		System.out.println(obscenitiesRemoved);
	}
	public boolean isObscene(Object obj){
		String potentialObscenity=obj.toString().toUpperCase();
		return this.obscenities.contains(potentialObscenity);
	}
	public void setBeanName(String name) {
		this.name=name;

	}
	

}