Spring Boot Simplifies Java Servlet Management

Before we talk about Spring Boot, first we need to understand “Servlet” and “Servlet container”. They provide a foundation for building a web application. A servlet is a Java class that handles client requests, processes them, and returns a response. And servlet containers are the ones that manage the servlet.

`java
@WebServlet("/demoServlet") //demoServlet is protected and mapped with URL pattern "/demoServlet"

{
doGet()
doPost()
}.
`

`xml
<servlet-mapping>
<servlet-name> DispatcherServlet </servlet-name>
<url-pattern> / </url-pattern>
</servlet-mapping>

<servlet>
<servlet-name> DispatcherServlet </servlet-name>
<servlet-class> org.springframework.web.servlet.DispatcherServlet </servlet-class>
</servlet>
`

Spring Frame work with example

(1) Removal of WebXML

– This WebXML over the times became too big and becomes very difficult to manage and understand .
→ Spring Frame work introduced Annotation based configuration.

(2) Inversion of control (IoC)

– IoC is more flexible way to manage object dependencies and its lifecycle.

1. Unit testing is much harder

– As the  object creation depends on servlet, mocking is not easy. Which makes unit testing process harder .

– Spring dependency injection facility makes the unit testing very easy.

2. Difficult to manage rest API

– Having different http methods request parameters, path making, code little difficult to understand .
– Spring MVC provides an organized approach to handle the request.

– The dynamic memory requires no static allocation in case of program allocation.
– The grid requires no static allocation in case of program and dynamic memory allocation is required at run time.
– The requirement for the dynamic memory program with only main framework with no memory allocation.
– Implement with minimum code size.
– Implement with minimum memory usage.
– Implement with maximum memory usage (may differ).
– Memory analysis part:
– Coding
– Memory
– Security.

Spring Boot Some Changes

1. Deployment Management – no need for adding different environments separately and no file comparison version handler

2. Auto Configuration – No need for support in configuring deployment server manually – “Environment” / “Component”

3. Embedded Server

4. To Health Spring MVC

Diagram:
– Entity
– Entity
– Entity
↓
– Common
– Service
– Repo

Notes:
– entity common mapped (common repo)
– DTO DAO annotated object

– Many
– validatory – compare – test
– package – many – manual – compare