Spring Framework defines some callback methods at the time of bean life cycle. These callback methods are used to perform some useful operations between the bean initialization to bean destroy. Spring provide two interface InitializingBean and DisposableBean, which provide two methods afterPropertiesSet() to allow initialization and destroy() for the destruction of bean respectively.

Example of Spring bean callback methods: Bean initialization callback:

public class Person implements InitializingBean  
{  
     @Override  
     public void afterPropertiesSet() throws Exception  
     {  
       //Do some initialization activity here  
       System.out.println("InitializingBean init method is called for Person");  
     }  
}  

Bean destruction callback:

public class Person implements DisposableBean   
{  
     @Override  
     public void destroy() throws Exception  
     {  
       //Do some Destruction works here  
       System.out.println("DisposableBean destroy method is called for Person");  
     }  
}  

But basically, we do not use above callback methods or interfaces, for best practice use the custom init and destroy methods. These methods configured with the bean in bean configuration file.These methods also called spring bean life cycle callback methods.

For Example:

bean.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"
  xmlns:c="http://www.springframework.org/schema/c"
  xsi:schemaLocation="http://www.springframework.org/schema/beans
      http://www.springframework.org/schema/beans/spring-beans.xsd">

  <bean id="person" class="com.evon.example.callbackMethodExample.Person" init-method="init" destroy-method="destroy">
  </bean>   
</beans>

Person.java

package com.evon.example.callbackMethodExample;
public class Person {
    private String name;
    private String city;

    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getCity() {
        return city;
    }
    public void setCity(String city) {
        this.city = city;
    } 

    //post-init method
    public void init() throws Exception {
        System.out.println("Person initializing.");
        if(getName() == null){
            setName("Pankaj");
        }
        if(getCity() == null){
            setCity("Dehradun");
        }
    }

    //pre-destroy method
    public void destroy() throws Exception {
        System.out.println("Person destroy.");
    }
}

Main.java

package com.evon.example.callbackMethodExample;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.FileSystemXmlApplicationContext;
public class Main {
    public static void main(String[] args) {
        ApplicationContext context = new FileSystemXmlApplicationContext("/src/main/java/com/evon/example/callbackMethodExample/bean.xml");
        Person person = (Person) context.getBean("person");
            System.out.println("Person name : "+person.getName());
            System.out.println("City name : "+person.getCity());
            ((FileSystemXmlApplicationContext)context).close(); 
    }
}

Output :

    Person initializing.
    Person name : Pankaj
    City name : Dehradun
    Person destroy.