"Welcome To Ashok IT"				
			                     "Spring Boot and MicroServices"
                                               Topic : Spring Data JPA - CrudRepoistory(I) Methods
                                               Date  : 05/10/2024
                                                (Session - 39)                  
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Today Session
==============

CrudRepoistory Interface Methods
================================
1) T save(T t) ::: This method is used for Saving given entity (or) Inserting Record.

2) Iterable<T> saveAll(Iterable<S> items) ::: This method is used for saving group of entities.

   NOTE 
   ====
   * Iterable is root interface of Collection interface and came in the version of Java 1.5

   * Iterable interface provides capability processing the collection object using "Enhanced For Loop" which came in the                    version of Java 1.5.

3) Optional<T> findById(Serializable id) ::: To retreive record based on the given primary key value.

   NOTE
   ====
   * Optional is an utility class from java8 Version which helps us to avoid the null checks in Java program.

   * Optional Class contains some utility methods to check whether object is present or not & We can get the object from                    optional object as below

       i) boolean isPresent()  

      ii) T get();

4) Iterable<T> findAllById(Iterable ids)  ::: To retreive records based on given primary key values.

5) Iterable<T> findAll() ::: To Retreive all the records from table.

6) void delete(T t) ::: Deleting record based on given entity.

7) void deleteById(Serializable id) ::: Deleting record based on given primary key

8) void deleteAllById(Iterable ids) ::: Deleting records based on given primary key values .

9) void deleteAll() ::: Deleting all records from table with out primary key

10) void deleteAll(Iterable<T> objects) ::: Deleting all records from table with out primary key

11) int count() :::: To get total records as count from table.

12) boolean existsById(Serializable id) ::: Check whether the record is existed or not for given primary key.

ShoppingCustomerService.java
============================
package com.ashokit.service;

import java.util.List;

import com.ashokit.entity.ShoppingCustomer;

public interface ShoppingCustomerService {
	
	//creating new customer record
	public ShoppingCustomer createNewBrandCustomer(ShoppingCustomer customer);
	
	//creating bulk of new customers
	public Iterable<ShoppingCustomer> createBulkNewBrandCustomers(List<ShoppingCustomer> customers);
	
	//Finding the customer By CustomerId
	public ShoppingCustomer findCustomerById(Integer customerId);
	
	//Finding All Customers
	public Iterable<ShoppingCustomer> fetchAllCustomers();

}

ShoppingCustomerServiceImpl.java
================================
package com.ashokit.service;

import java.util.List;
import java.util.Optional;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import com.ashokit.dao.ShoppingCustomerRepo;
import com.ashokit.entity.ShoppingCustomer;

@Service
public class ShoppingCustomerServiceImpl implements ShoppingCustomerService {
	
	@Autowired
	private ShoppingCustomerRepo customerRepo;

	@Override
	public ShoppingCustomer createNewBrandCustomer(ShoppingCustomer customer) {
		
		System.out.println("Repo Implementation Class Name::::" + customerRepo.getClass().getName());
		
		ShoppingCustomer savedCustomerInfo = customerRepo.save(customer);
		
		return savedCustomerInfo;
	}

	@Override
	public Iterable<ShoppingCustomer> createBulkNewBrandCustomers(List<ShoppingCustomer> customers) {
		
		Iterable<ShoppingCustomer> savedCustomers = customerRepo.saveAll(customers);
		
		return savedCustomers;
	}

	@Override
	public ShoppingCustomer findCustomerById(Integer customerId) {
		
		//Getting the CustomeDetails based On CustomerId
		Optional<ShoppingCustomer> customerDetails = customerRepo.findById(customerId);
		
		//checking the customerDetails optional object
		if(customerDetails.isPresent()) {
			 ShoppingCustomer shoppingCustomer = customerDetails.get();
			 return shoppingCustomer;
		}else {
			//Throw the Exception 
			return null;
		}
	}

	@Override
	public Iterable<ShoppingCustomer> fetchAllCustomers() {
		
		Iterable<ShoppingCustomer> allCustomers = customerRepo.findAll();
		
		return allCustomers;
	}

}

ShoppingCustomerController.java
===============================
package com.ashokit.controller;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;

import com.ashokit.entity.ShoppingCustomer;
import com.ashokit.service.ShoppingCustomerService;

@Controller
public class ShoppingCustomerController {
	
	@Autowired
	private ShoppingCustomerService customerService;
	
	public void createNewCustomer(ShoppingCustomer customer) {
		ShoppingCustomer customerDetails = customerService.createNewBrandCustomer(customer);
		System.out.println("New Customer Got Created Successfully......");
		System.out.println(customerDetails);
	}
	
	public void createBulkNewCustomers(List<ShoppingCustomer> customerList) {
		
		Iterable<ShoppingCustomer> savedCustomers = customerService.createBulkNewBrandCustomers(customerList);
		
		//forEach() from Java1.8 version which accepts Consumer FunctionaInterface as parameter
	    //Consumer Functional Interface abstract method implementation we can provide through LambdaExpression
		//Consumer FI contains one abstract method i.e.,accept(T t)
	    savedCustomers.forEach(eachCustomer -> System.out.println(eachCustomer));
		
	}
	
	public void fetchCustomerDetailsById(Integer customerId) {
	    ShoppingCustomer customerDetails = customerService.findCustomerById(customerId);
	    System.out.println(customerDetails);
	}
	
	public void fetchAllCustomersDetails() {
		Iterable<ShoppingCustomer> customerDetails = customerService.fetchAllCustomers();
		//processing Java8 forEach loop
		customerDetails.forEach(eachCustomer -> System.out.println(eachCustomer));
	}
}

Application.java
=================
package com.ashokit;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

import com.ashokit.controller.ShoppingCustomerController;
import com.ashokit.entity.ShoppingCustomer;

@SpringBootApplication
public class Application implements CommandLineRunner{

	@Autowired
	private ShoppingCustomerController customerController;
	
	public static void main(String[] args) {
		SpringApplication.run(Application.class, args);
	}
	
	@Override
	public void run(String... args) throws Exception {
		
		//New Customer Information
		ShoppingCustomer customer1 = new ShoppingCustomer(123,"Mahesh","Hyderabad","mahesh.ashokit@gmail.com","123456789");
		ShoppingCustomer customer2 = new ShoppingCustomer(124,"Suresh","Pune","suresh.ashokit@gmail.com","545454454");
		ShoppingCustomer customer3 = new ShoppingCustomer(125,"Rajesh","Chennai","rajesh.ashokit@gmail.com","23323232");
		ShoppingCustomer customer4 = new ShoppingCustomer(126,"Ramesh","Hyderabad","ramesh.ashokit@gmail.com","121212121");
		
		//calling the Controller class method for creating new customer
		//customerController.createNewCustomer(newCustomerInfo);
		
		//customerController.createBulkNewCustomers(List.of(customer1,customer2,customer3,customer4));
		
		//customerController.fetchCustomerDetailsById(124);
		
		customerController.fetchAllCustomersDetails();
	}
}

OUTPUT-1(Bulk Records Insertion)
========

  .   ____          _            __ _ _
 /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
 \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::                (v3.1.1)

ShoppingCustomer [custId=123, name=Mahesh, location=Hyderabad, email=mahesh.ashokit@gmail.com, contactNo=123456789]
ShoppingCustomer [custId=124, name=Suresh, location=Pune, email=suresh.ashokit@gmail.com, contactNo=545454454]
ShoppingCustomer [custId=125, name=Rajesh, location=Chennai, email=rajesh.ashokit@gmail.com, contactNo=23323232]
ShoppingCustomer [custId=126, name=Ramesh, location=Hyderabad, email=ramesh.ashokit@gmail.com, contactNo=121212121]

OUTPUT-2(Finding Customer Details)
========

  .   ____          _            __ _ _
 /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
 \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::                (v3.1.1)

ShoppingCustomer [custId=124, name=Suresh, location=Pune, email=suresh.ashokit@gmail.com, contactNo=545454454]

OUTPUT-3(Fetching All Customers)
========

  .   ____          _            __ _ _
 /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
 \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::                (v3.1.1)

ShoppingCustomer [custId=123, name=Mahesh, location=Hyderabad, email=mahesh.ashokit@gmail.com, contactNo=123456789]
ShoppingCustomer [custId=124, name=Suresh, location=Pune, email=suresh.ashokit@gmail.com, contactNo=545454454]
ShoppingCustomer [custId=125, name=Rajesh, location=Chennai, email=rajesh.ashokit@gmail.com, contactNo=23323232]
ShoppingCustomer [custId=126, name=Ramesh, location=Hyderabad, email=ramesh.ashokit@gmail.com, contactNo=121212121]

Assignment
==========
* Develop the Service method & Controller Methods for findAllById(Iterable<ID> ids).

* Develop the service method & controller method for Count().

* Develop the service method & controller method for deleteAllById(Iterable<ID> ids)

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