Java/Spring/BeanPostProcessor

Add BeanPostProcessor To XmlBeanFactory

       
File: context.xml
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN"
    "http://www.springframework.org/dtd/spring-beans.dtd">
<beans>
  <bean id="w" class="java.lang.String">
  </bean>
 
  <bean id="beanInitLogger" class="BeanInitializationLogger"/>
</beans>

File: Main.java
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.config.BeanPostProcessor;
import org.springframework.beans.factory.xml.XmlBeanFactory;
import org.springframework.core.io.ClassPathResource;
class Main {
  public static void main(String args[]) throws Exception {
    XmlBeanFactory factory = new XmlBeanFactory(new ClassPathResource("context.xml"));
    BeanInitializationLogger logger = new BeanInitializationLogger();
    factory.addBeanPostProcessor(logger);

    factory.preInstantiateSingletons();
  
  }
}
class BeanInitializationLogger implements BeanPostProcessor {
  public Object postProcessBeforeInitialization(Object bean, String beanName)
      throws BeansException {
    return bean;
  }
  public Object postProcessAfterInitialization(Object bean, String beanName)
      throws BeansException {
    
    System.out.println("Bean "" + beanName + "" initialized");
    return bean;
  }
}

Implements BeanPostProcessor

       
File: context.xml
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN"
    "http://www.springframework.org/dtd/spring-beans.dtd">
<beans>
  <bean id="w" class="java.lang.String">
  </bean>
 
  <bean id="beanInitLogger" class="BeanInitializationLogger"/>
</beans>

File: Main.java
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.config.BeanPostProcessor;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
class Main {
  public static void main(String args[]) throws Exception {
    ApplicationContext ctx = new ClassPathXmlApplicationContext("context.xml");
    ctx.getBean("w");
    
  
  }
}
class BeanInitializationLogger implements BeanPostProcessor {
  public Object postProcessBeforeInitialization(Object bean, String beanName)
      throws BeansException {
    return bean;
  }
  public Object postProcessAfterInitialization(Object bean, String beanName)
      throws BeansException {
    
    System.out.println("Bean "" + beanName + "" initialized");
    return bean;
  }
}