JAVA EE: Spring Bean Life Cycle - BeanNameAware Interface | Spring Tutorial

Monday, 27 August 2018

Spring Bean Life Cycle - BeanNameAware Interface | Spring Tutorial | Spring Framework

🚀 Master Core Java & Spring Framework Step-by-Step!

What is the BeanNameAware Interface?

In the Spring Framework, when a bean needs to be aware of its own name configured within the Spring container, it implements the BeanNameAware interface. This is one of the built-in Aware interfaces provided by Spring to supply metadata back to the bean itself.

Where Does It Fit in the Spring Bean Life Cycle?

During the bean creation lifecycle, the Spring container performs the following sequence:

Instantiates the bean object.
Populates all dependencies and properties.
Checks if the bean implements any Aware interfaces.
If BeanNameAware is implemented, it invokes setBeanName(String name) and injects the configured bean name.

Example Code

public class SampleBean implements BeanNameAware {
    private String beanName;

    @Override
    public void setBeanName(String name) {
        this.beanName = name;
        System.out.println("Bean configured name is: " + name);
    }
}

Related Spring Tutorials to Watch Next

Click here to watch on Youtube:
https://www.youtube.com/watch?v=HP2_M5JlvtU&list=UUhwKlOVR041tngjerWxVccw

Click the below Image to Enlarge:

Spring Bean Life Cycle - BeanNameAware Interface | Spring Tutorial | Spring Framework

pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0%20http://maven.apache.org/maven-v4_0_0.xsd">

    <modelVersion>4.0.0</modelVersion>

    <groupId>com.ram.core</groupId>

    <artifactId>SpringDemo</artifactId>

    <packaging>jar</packaging>

    <version>1.0-SNAPSHOT</version>

    <name>SpringDemo</name>

    <url>http://maven.apache.org</url>

    <properties>

        <spring.version>5.0.2.RELEASE</spring.version>

    </properties>

    <dependencies>

        <dependency>

            <groupId>junit</groupId>

            <artifactId>junit</artifactId>

            <version>3.8.1</version>

            <scope>test</scope>

        </dependency>

        <!-- Spring 5 dependencies -->

        <dependency>

            <groupId>org.springframework</groupId>

            <artifactId>spring-core</artifactId>

            <version>${spring.version}</version>

        </dependency>

        <dependency>

            <groupId>org.springframework</groupId>

            <artifactId>spring-context</artifactId>

            <version>${spring.version}</version>

        </dependency>

    </dependencies>

</project>

BeanNameAwareImpl.java

package com.ram.aware;

import org.springframework.beans.factory.BeanNameAware;

public class BeanNameAwareImpl implements BeanNameAware

{

    public void setBeanName(String beanName)

    {

        System.out.println(

                "setBeanName(String beanName) is called by the Spring Container");

        System.out.println("Bean name = " + beanName);

    }

}

applicationContext.xml

<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-4.3.xsd">

    <bean id="beanNameAware" class="com.ram.aware.BeanNameAwareImpl"/>

</beans>

App.java

package com.ram.core;

import org.springframework.context.support.ClassPathXmlApplicationContext;

import com.ram.aware.BeanNameAwareImpl;

public class App

{

    public static void main(String[] args)

    {

        ClassPathXmlApplicationContext applicationContext = new ClassPathXmlApplicationContext(

                "applicationContext.xml");

        BeanNameAwareImpl beanNameAwareImpl = applicationContext

                .getBean("beanNameAware", BeanNameAwareImpl.class);

        System.out.println("beanNameAwareImpl = "+beanNameAwareImpl);

        applicationContext.close();

    }

}

Output

Aug 12, 2018 12:10:47 PM org.springframework.context.support.AbstractApplicationContext prepareRefresh

INFO: Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@5b37e0d2: startup date [Sun Aug 12 12:10:47 IST 2018]; root of context hierarchy

Aug 12, 2018 12:10:47 PM org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions

INFO: Loading XML bean definitions from class path resource [applicationContext.xml]

setBeanName(String beanName) is called by the Spring Container

Bean name = beanNameAware

beanNameAwareImpl = com.ram.aware.BeanNameAwareImpl@5c7fa833

Aug 12, 2018 12:10:47 PM org.springframework.context.support.AbstractApplicationContext doClose

INFO: Closing org.springframework.context.support.ClassPathXmlApplicationContext@5b37e0d2: startup date [Sun Aug 12 12:10:47 IST 2018]; root of context hierarchy