The @PostConstruct and @PreDestroy annotation are J2ee specific, lies in common-annotations.jar.

Customer.java File

package com.jtechies;

import javax.annotation.PostConstruct;
import javax.annotation.PreDestroy;

public class Customer {
	private String message;

	public String getMessage() {
		return message;
	}

	public void setMessage(String message) {
		this.message = message;
	}
	
	@PostConstruct
	public void init()throws Exception{
		System.out.println("Inside Init() method...");
	}
	@PreDestroy
	public void destroy()throws Exception{
		System.out.println("Inside Destroy() method...");
	}
}

Test.java File

package com.jtechies.test;

import org.springframework.context
		.ConfigurableApplicationContext;
import org.springframework.context.support.
		ClassPathXmlApplicationContext;

import com.jtechies.Customer;

public class Test {
	public static void main(String[] args) {
		ConfigurableApplicationContext context = new
			ClassPathXmlApplicationContext("spring.xml");
		Customer customer = (Customer)
			context.getBean("customer");
		System.out.println(customer.getMessage());
		context.close();
	}
}

spring.xml File

To enable @PostConstruct and @PreDestroy annotation, you have to either register 'CommonAnnotationBeanPostProcessor' or specify the '<context:annotation-config />' in bean configuration file,

<?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:context=
		"http://www.springframework.org/schema/context"
	xsi:schemaLocation=
		"http://www.springframework.org/schema/beans 
	http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
	http://www.springframework.org/schema/context 
	http://www.springframework.org/schema/context/spring-context-3.0.xsd">

	<context:annotation-config/>
	
	<bean id="customer" class="com.jtechies.Customer">
	<property name="message" value="Hi i am a customer"/>
	</bean>
	
</beans>

Output

Inside Init() method...
Hi i am a customer
Inside Destroy() method...

The init() method is called, after the message property is set, and the destroy() method is call after the context.close();