"Welcome To Ashok IT"				
			                     "Spring Boot and MicroServices"
                                              Topic : Steps For Developing First Spring Application
                                              Date  : 22/08/2024
                                                (Session - 07)                               
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Yesterday Session : Developing First Spring Application 
=======================================================
* Developing the First Spring Application by using setter Injection with help of STS IDE.

Step-1 : Configure workspace for our application 
================================================
   F:\ASHOKIT_WORKSPACE\47_SPRINGBOOT_AND_MICROSERVICES\APPS_WORKSPACE

Step-2: Opening the STS IDE
===========================
 * Yesterday we downloaded the STS IDE from web as JAR File.

 * We need to extract that JAR File into normal folder just by double clicking on it JAR File.

 * Onces we got the normal Folder from JAR File >>> Need to find icon sts as "SpringToolSuite4.exe" and double click on it.

 * It prompt you configure the workspace folder(Where we need to save of our all projects) and provide required location
   in the dialog box i.e.,
         
           "F:\ASHOKIT_WORKSPACE\47_SPRINGBOOT_AND_MICROSERVICES\APPS_WORKSPACE"

Step-3: Creating Maven Project
==============================
 Maven >>>> It is build tool for Java Projects.
  
       >>>> By using build tool we can compile source code,execute test cases,packaging,executing the Application of Java                 Project.

       >>>> By using maven we can download the JAR files/download dependencies required for Project.

       >>>> When we create maven project either from Eclipse IDE/STS IDE/IntelliJ IDE will get one default configuration file
             i.e.,pom.xml

       >>>> POM Stands Project Object Model can be used to define information about project & Dependencies required for                  project

       >>>> In Maven we have three kinds of repositories that are required for collecting JAR files

            1) Central Repoistory : Every one access the Repo in the following URL(https://mvnrepository.com/)
 
            2) Local Repoistory   : The Repository which resides inside our local machine(.m2 >>> C:/Users/NEW/.m2)

            3) Remote Repoistory  : The Repoistory which can be hosted in artifactories to collect JAR Files(JFrog,Nexus)

       >>>> We no need to download maven software manually because almost all IDE having support with MAVEN.

       >>>> Maven Terminiologies

             groupId ::: company name/ Organization name Ex: org.springframework

             artifactId :::: Project Name/Module-Name  Ex: spring-core

             version :::::: Configure the Required version.

       >>>> Maven provided the predefined Project templates(2000+) i.e.,archetypes

             maven-archetype-quickstart >>>>>>>>>>> This archetype used for developing the standalone APplication in java

             maven-archetype-web >>>>>>>>>>>>>>>>>> This archetype used for developing the webapplication in java.    

  Creating Maven Project 
  ======================
  * In the Package Explorer section we have option i.e.,"Create Maven Project" simply click on it.

  * We need to find the quickstart archetype  "maven-archetype-quickstart" (Maven Related Archetypes)

  * Fill the below inputs on Maven Dialog box

      groupId >>>>> ashokit
 
      artifactId >>>>>>> 01_SpringCore_DependencyInjection_App

      Version  >>>>>>>>0.0.1-SNAPSHOT

      package  >>>>>>>> com.ashokit        

  * After the providing the above data we need to click on "Finish" button for creating Maven Project in STS IDE.

Step-4: Exploring the Project Structure
=======================================
* After creating the Maven project in STS IDE simple we need expand the Project so that we can find below details

       src/main/java >>>>>>>>>>> We can place our source code

       src/test/java >>>>>>>>>>> We can place our test case related source code.

       JRE_System_Library >>>>>>>> We can have Java related base libraries

       MAVEN Dependencies >>>>>>>> It contains Jars Information through MAVEN Download

       pom.xml  >>>>>>>>>>> Default maven configuration file.

* Configure the Spring Dependencies in pom.xml under <dependencies> section 

	<!-- https://mvnrepository.com/artifact/org.springframework/spring-context-support -->
	<dependency>
    		<groupId>org.springframework</groupId>
  	        <artifactId>spring-context-support</artifactId>
	       <version>6.1.12</version>
        </dependency>

* changing the Java Compiler version from 1.7 to 17 version with below tags in pom.xml

                <maven.compiler.source>17</maven.compiler.source>
		<maven.compiler.target>17</maven.compiler.target>

* Reflect the changes to our maven project we need to perform maven update project

   Right click on project  >>>> Select Maven option >>>> Again select "Update Project" >>> Check the checkbox(force update       snapshots/release) >>>>>  Finally click on "Ok" button.

Step-5: Creating the Spring Bean class
======================================
* Before Creating the Spring Bean Class firt we need one package under "src/main/java" for storing spring beans and package    name is "com.ashokit.spring.beans".

* After creating the package we need to add the new Java class by simply right click on package >>>>> New Option >>>>>    Select "Class" option.

Welcome.java
============
package com.ashokit.spring.beans;

public class Welcome {

	//Defining the Property
	private String message;
	
	//Defining the setter method used for Setter Injection
	public void setMessage(String message) {
		this.message = message;
	}
	
	public String getMessage() {
		return message;
	}
}


Demo.java
=========
package com.ashokit.spring.beans;

public class Demo {
	
	//Defining the Property
	private String topicName;
	
	//Defining the Constructor
	public Demo() {
		System.out.println("Spring Bean Demo Clas....");
	}
	
	//Defining the Constructor to inject the value for topicName
	public Demo(String topicName) {
		this.topicName = topicName;
	}

	@Override
	public String toString() {
		return "Demo [topicName=" + topicName + "]";
	}
}


Step-6: Creating the Spring Configuration File
==============================================
* Before creating the spring configuration file we need to create one package to store spring configuration file.

* Right click on "src/main/java" >>>> Select "New" Option >>>> Again select "Package" option >>>> Specify the package name     i.e.,com.ashokit.spring.config.

* Select created package and right click on it  >>>> Select New option >>>> Find "File" option >>> specify the file name 
  i.e.spring.xml(or) application.xml

spring.xml
==========
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:p="http://www.springframework.org/schema/p"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
       https://www.springframework.org/schema/beans/spring-beans.xsd">
   
   <!-- configuring the Java Class as spring Bean -->
   <bean id="wb" class="com.ashokit.spring.beans.Welcome">
	   
	   <!-- Injecting the value of message property using setter method -->
	    <property name="message" value="Welcome To AshokIT For Spring Framework"/>
	    
   </bean>
   
      <!-- configuring the Java Class as spring Bean -->
   <bean id="db" class="com.ashokit.spring.beans.Demo">
	   
	   <!-- Injecting the value of message property using constructor method -->
        <constructor-arg name="topicName" value="Welcome To AshokIT For Spring Framework"/>
	    
   </bean>       
       
</beans>       

NOTE
====
 * Collect the xmlns from web i.e.,https://docs.spring.io/spring-framework/reference/core/beans/introduction.html

 * Root tag for every spring configuration file will be <beans> tag.

 * <bean> tag is used for representing the Java Class as Spring Bean Class.

 * <property> tag is used to perform setter injection by the IOC Container.

Step-7: Preparing the SpringClient Application
==============================================
* SpringClient application is nothing main class of our Spring Application (or) entry point to execute the program.

* We need to follow below points to get Demo class Object (or) Welcome Class Object from IOC Container.

  1) Locate the Spring Configuration file by using Resource Interface and implementation class of "ClassPathResource".

       Spring Configuration file >>>>>>>>>>>>>>>> com/ashokit/spring/config

       Resource resource = new ClassPathResource("com/ashokit/spring/config/spring.xml");

        Resource is an interface froma Spring API and implementation class will be  "ClassPathResource".

        ClassPathResource is used to find the spring configuration file in classpath itself.

        FileSystemResource is used to find the spring configuration file in our FileSystem.

  2) Activate the Spring Container i.e.,BeanFactory in spring application

      BeanFactory (I) and Implementation class (XmlBeanFactory)

      BeanFactory factory = new XmlBeanFactory(resource);

      Programmer is activating the Spring Container so that onces its got Activated It will read the Spring Configuration       file based on Resource object.  

      Spring Container will get to know what are the different spring beans are available in our project.

 
  3) Requesting the spring bean object from BeanFactory container

      Demo db = (Demo)factory.getBean("db");  // here db means spring bean id

      Welcome wb = (Welcome)factory.getBean("wb");// here wb means spring bean id

     * getBean() will return the Object of java.lang.Object programmer need to typecast to required spring bean.

  4) Printing the Spring Bean Objects

        System.out.println(wb);
    	System.out.println(db);

Step-8: Run the Spring Application
===================================
 * open App.java and right click on it  and find "Run-As" >>>> Choose "Java Application" option

OUTPUT
======
Spring Bean Welcome Clas....
Setter Method called from Welcome Class
Demo Class Constructor
Welcome [message=Welcome To AshokIT For Spring Framework]
Demo [topicName=Welcome To AshokIT For Spring Framework]
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