Spring is a powerful and widely-used Java framework for building enterprise-level applications. It provides a comprehensive set of tools, libraries, and components for developing robust, scalable, and maintainable Java applications. Spring follows the principles of inversion of control (IoC) and dependency injection (DI), promoting loose coupling and modular design. It offers features like aspect-oriented programming (AOP), transaction management, security, and integration with various data storage solutions.

Module 1: Introduction to Spring Framework

What is Spring?

Spring is a powerful, lightweight application framework designed for the Enterprise Java platform. It offers a complete suite for building applications, from configuration, security, web applications, data access, messaging, and more.

Setting Up a Spring Project

A Spring Boot project can be set up by using Spring Initializer, an online tool that allows to configure the basic details of your project.

// Use Spring Initializer (start.spring.io) to set up a project. Select the desired specifications and generate the project.

Module 2: Dependency Injection and Spring Beans

Dependency Injection

Dependency Injection (DI) is a pattern that decouples the dependencies of an application. Spring provides DI via either XML configuration or annotations.

private EmployeeService employeeService;

Spring Beans

Spring Beans are the objects that form the backbone of the application. They are managed by the Spring IoC container.

public class Employee {...}

Module 3: Data Access with Spring

Spring Data JPA

Spring Data JPA, part of the larger Spring Data family, makes it easy to implement JPA-based repositories. This module deals with enhanced support for JPA-based data access layers.

public interface EmployeeRepository extends JpaRepository<Employee, Long> {...}

Transaction Management

Spring provides a consistent transaction management interface that can scale down to a local transaction (using a single database, for example) and scale up to global transactions (using JTA, for example).

public void performOperation() {...}

Module 4: Spring MVC

Controllers and Views

Spring MVC offers annotations to map requests and to express request mapping conditions.

public class EmployeeController {
	public String getEmployee(Model model) {...}

Form Handling

Spring MVC supports form handling and provides all the necessary configuration via annotations. You can bind form elements to Model objects.

public String saveEmployee(@ModelAttribute('employee') Employee employee, BindingResult result, Model model) {...}

Module 5: Security with Spring Security

Security Configuration

Spring Security is a powerful and highly customizable authentication and access-control framework. It provides protection against attacks like session fixation, clickjacking, cross-site request forgery, etc.

public class SecurityConfig extends WebSecurityConfigurerAdapter {...}

Authentication and Authorization

Spring Security provides authentication and authorization features, protecting application from unauthorized access.

public String securedMethod() {...}