What is servlet packaging?
servlet package contains a number of classes and interfaces that describe and define the contracts between a servlet class and the runtime environment provided for an instance of such a class by a conforming servlet container.
Which package needs to be imported for a servlet?
Creating Servlets in Packages myorg; // Import required java libraries import java.io. *; import javax. servlet.
Which package is required while writing a servlet code?
A servlet shall be kept inside a Java package (instead of the default no-name package) for proper deployment. Let’s call our package ” mypkg “. Create a sub-directory called ” mypkg ” under ” WEB-INF\src “. Use a programming text editor to enter the following source codes, and save as ” HelloServlet.
How are Servlets loaded?
The java servlet container first creates the servlet instance and then executes the init() method. Servlet are loaded in the order of number(non-zero-integer) specified. That is, lower(example: 1) the load-on-startup value is loaded first and then servlet with higher values are loaded.
Which method is called only once in servlet life cycle?
init() Method
Why do we use servlets?
A servlet is a Java programming language class that is used to extend the capabilities of servers that host applications accessed by means of a request-response programming model. Although servlets can respond to any type of request, they are commonly used to extend the applications hosted by web servers.
What are the problems with servlets?
Here are cons/drawbacks for using servlet:
- One servlet is loaded into JVM.
- When there is a request, there is a thread, not a process.
- Servlet is persistent until it destroys.
- Designing in a servlet is difficult and slows down the application.
- You need a JRE(Java Runtime Environment) on the server to run servlets.
Is Servlet a framework?
In contrast, Struts and the Spring MVC Framework are action-oriented frameworks that provide a thinner abstraction layer over the servlet API….At a glance.
| Action-based frameworks: | Apache Struts, Spring MVC |
|---|---|
| Web template systems: | Apache Tiles, SiteMesh, Thymeleaf |
Which is faster JSP or servlet?
Servlets are faster as compared to JSP, as they have a short response time. JSP is slower than Servlets, as the first step in the JSP lifecycle is the conversion of JSP to Java code and then the compilation of the code. Servlets are Java-based codes.
What is Servlet and its advantages?
The advantages of Servlet are as follows: Better performance: because it creates a thread for each request, not process. Portability: because it uses Java language. Robust: JVM manages Servlets, so we don’t need to worry about the memory leak, garbage collection, etc. Secure: because it uses java language.
What replaced servlets?
Below are some alternatives to servlets:
- Common Gateway Interface (CGI) It is the most typical server-side solution.
- Proprietary API. Many proprietary web servers have built-in support for server-side programming.
- Active Server Pages (ASP)
- Serverside JavaScript.
What is servlet and its types?
servlet. HTTP servlets provide a service method that automatically routes the request to another method in the servlet based on which HTTP transfer method is used. So, for HTTP servlets, override doPost() to process POST requests, doGet() to process GET requests, and so on.
What is servlet and how it works?
Servlets are the Java programs that runs on the Java-enabled web server or application server. They are used to handle the request obtained from the web server, process the request, produce the response, then send response back to the web server. Properties of Servlets : Servlets work on the server-side.
What are the methods in servlet?
Methods of Servlet interface
| Method | Description |
|---|---|
| public void destroy() | is invoked only once and indicates that servlet is being destroyed. |
| public ServletConfig getServletConfig() | returns the object of ServletConfig. |
| public String getServletInfo() | returns information about servlet such as writer, copyright, version etc. |
What are the functions of servlet container?
The main functions of Servlet container are:
- Lifecycle management : Managing the lifecycle events of a servlet lik class loading, instantiation, initialization, service, and making servlet instances eligible for garbage collection.
- Communication support : Handling the communication between servlet and Web server.
What happens when the first request for the servlet method is received?
When the first client request comes in, the Container starts a new thread or allocates a thread from the pool, and causes the servlet’s service() method to be invoked. This method looks at the request, determines the HTTP method (GET, POST, etc.) on the servlet.
What is the life cycle of servlet?
The Servlet Life Cycle is the entire process of its creation till the destruction. servlet web container maintains the servlet lifecycle. Three methods are central to the life cycle of a servlet. These are init(),service() and destroy().