Aggregating @Configuration classes with @Import | Spring Tutorial

Click here to watch on Youtube:

https://www.youtube.com/watch?v=GRitnworI4c&list=UUhwKlOVR041tngjerWxVccw

Click the below Image to Enlarge:

Aggregating @Configuration classes with @Import | Spring Tutorial

Aggregating @Configuration classes with @Import | Spring Tutorial

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 http://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>SpringHelloWorld</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>

Employee.java

package com.ram.core;

/**
 * Spring bean
 *
 */
public class Employee
{
    private String name;

    public Employee(String name)
    {
        System.out.println(this.getClass().getName()
                + ", Employee(String name) constructor is called, " + name);

        this.name = name;
    }


    public void employeeDetails()
    {
        System.out.println("Employee Name =  " + name);
    }
}

Customer.java

package com.ram.core;

/**
 * Spring bean
 *
 */
public class Customer
{
    private String name;

    public Customer(String name)
    {
        System.out.println(this.getClass().getName()
                + ", Customer(String name) constructor is called, " + name);

        this.name = name;
    }

    public void customerDetails()
    {
        System.out.println("Customer Name =  " + name);
    }
}

EmployeeConfig.java

package com.ram.config;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import com.ram.core.Employee;

@Configuration
public class EmployeeConfig
{

    @Bean(name = "employee")
    public Employee employee()
    {

        System.out.println(
                "In EmployeeConfig employee() is called by the Spring container");
        return new Employee("Peter");

    }
}

CustomerConfig.java

package com.ram.config;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import com.ram.core.Customer;

@Configuration
public class CustomerConfig
{

    @Bean(name = "customer")
    public Customer customer()
    {
        System.out.println(
                "In CustomerConfig employee() is called by the Spring container");
        return new Customer("John");
    }

}

AppConfig.java

package com.ram.config;

import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;

@Configuration
@Import({ EmployeeConfig.class, CustomerConfig.class })
public class AppConfig
{

}

App.java

package com.ram.core;

import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;

import com.ram.config.AppConfig;

public class App
{
    public static void main(String[] args)
    {
        ApplicationContext context = new AnnotationConfigApplicationContext(
                AppConfig.class);

        System.out.println("---------------------------------------");
     
        Employee employee = (Employee) context.getBean("employee");
        System.out.println("Got employee object from the ApplicationContext");
        employee.employeeDetails();
     
        System.out.println("---------------------------------------");
     
        Customer customer = (Customer) context.getBean("customer");
        System.out.println("Got customer object from the ApplicationContext");
        customer.customerDetails();

    }
}

Output

Oct 07, 2018 7:32:15 AM org.springframework.context.support.AbstractApplicationContext prepareRefresh
INFO: Refreshing org.springframework.context.annotation.AnnotationConfigApplicationContext@5f4da5c3: startup date [Sun Oct 07 07:32:15 IST 2018]; root of context hierarchy
In EmployeeConfig employee() is called by the Spring container
com.ram.core.Employee, Employee(String name) constructor is called, Peter
In CustomerConfig employee() is called by the Spring container
com.ram.core.Customer, Customer(String name) constructor is called, John
---------------------------------------
Got employee object from the ApplicationContext
Employee Name =  Peter
---------------------------------------
Got customer object from the ApplicationContext
Customer Name =  John

Click the below link to download the code:
https://sites.google.com/site/ramj2eev2/java_basics/SpringDemo_aggregate_import.zip?attredirects=0&d=1

Github Link:
https://github.com/ramram43210/javaee/tree/master/Spring_2018/SpringDemo_aggregate_import

Bitbucket Link:
https://bitbucket.org/ramram43210/spring/src/e16b8c6ef73a72464fa5812e24080179c4adc913/Spring_2018/SpringDemo_aggregate_import/?at=master

See also:

All JavaEE Videos Playlist

All JavaEE Videos

All JAVA EE Links

Spring Tutorial

Servlets Tutorial

All Design Patterns Links

JDBC Tutorial

Java Collection Framework Tutorial

JAVA Tutorial

Kids Tutorial

Cooking Tutorial