Updated May 30, 2023
Introduction to JSP
JSP stands for Java Servlet pages, is a technology used for creating web pages that support dynamic content, provides various special JSP tags to retrieve the data from databases, access java bean components, share information between requests and pages, etc. So that developers can use it to add java code in HTML files, XML, soap, or other document types. Pages created using JSP are quite fast and easy to build, collect user data through forms, databases, or other sources and create a dynamic webpage.
What is JSP?
It is an acronym for Java Server Pages. It is a server-side technology that helps developers or users to generate web-based pages. The feature of Servlets, which is an improvement, was developed by Sun Microsystems. Developers created JSP to address all the shortcomings of Servlets. Servlets used to contain a combined logic of businesses and user interface. In JSP, developers separate the presentation logic and business logic. As we have scripted or used earlier, tags define a specific action. In JSP, we define the special tag as “<% %>.” We can implement the Java APIs by default into the web programming when we use JSP. The Java APIs and JSP work with HTML and XML tags, which was previously impossible. As we use in Java, JDBC database drivers can be utilized too. So dynamic querying of a database is possible. Apart from regular usage,
It provides more features like:
- Querying the database and retrieving information.
- Sharing information between two pages.
- Access Control.
Why do we Need JSP?
Being a server-side programming language, it helps in creating dynamic web pages. Not only with Java APIs but a connection with the database is an added advantage, which was previously impossible. In JSP, you can combine action commands and textual data. You can extract values from dynamic content, such as checkboxes and action buttons. It can access JavaBeans or an object of it too.
Diagrammatic Explanation of Working with JSP:
Till now, we have seen so many uses of JSP; it is making a life of developers easier by letting them access such considerable amounts of data and other syntactical language scripts. A Java Server Page undergoes translation into a regular Servlet initially. As any servlet would do, it translates the requests, but the first time only, unlike servlets. The translator recognizes the file name with its extension as “.jsp” to obtain the result. The servlet processes it again, or it can generate a “.jsp” output. The execution of JSP pages typically follows the following sequential order:
- The browser sends a normal request to the server.
- The server recognizes it as a JSP page and sends it to the JSP server for execution. The server acknowledges this by locating the page with the extension as “.jsp.”
- It is converted into a servlet.
- The engine converts the servlet into an executable class.
- After obtaining the output, the system converts it into an HTML format and sends it to the web browser.
Why and How Should We Use JSP?
It offers several features and describes why and how we should use it:
1. Translation: When a code is written, a Java Servlet file is created of a “.jsp” file. When you write a code file with HTML and JSP tags but you use the file extension “.jsp,” it undergoes translation into a servlet file. This is the first step in the life cycle.
2. Compilation: In this step, a servlet class previously available in the step is created into a servlet class file.
Ex: emp_jsp.java into emp_jsp.class
This compilation generally happens during deployment.
3. Loading: The class created gets loaded into the container class loader.
4. Initiation: In an instance of this class, an object is created. The container can manage one or more instances as per the need. So, as we have seen, an object in Java calls a class, and similar things occur here. Init() and destroy() actions take place in this initiation phase.
5. Initialization: JSP init(), the container calls a method, and the initialization occurs.
6. Processing: All the services and requests are processed. The server processes both GET() and POST() requests.
7. Destroy: In this method, the instance created is destroyed as all the actions needed are processed and done.
Advantages and disadvantages
Below are the advantages and disadvantages:
- Being an extension of Java Servlet, it can use every feature of Java Servlet. Additionally, it supports the use of custom tags.
- There is no need to recompile JSP when changed. The changes automatically appear when run.
- The tags used are easy to comprehend and write.
- The Java API is now easily usable and integrated with the HTML code, providing support for it.
- The obtained results are in HTML format, which can be opened on any browser.
- You can use customized JSP tags. Ex: Tags with XML.
- Rather than changing every page, it is possible to add changes to the business logic page.
- Though the database can be accessed with JSP, it is not easy to access as most of the servlet does not provide support.
- Being a servlet, it becomes very hard to trace if there’s an issue in the code.
- The compilation time required is more than on a server.
How will this Technology Help you Grow your Career?
With advancements in every aspect of the IT field and the online market. The development and advancements will increasingly require the Java Servlet page to play a vital role. Users will use database connectivity far more thoroughly as a feature. People with minimum knowledge of HTML and JAVA can also use the Java Servlet page, which is very easy to handle, and the calls can be easily written with help. Servlet works exactly like a JAVA class, so with all the features of JAVA, it makes JSP more likely to get used.
This is right now, and in the coming days will be needed more and more as everything is coming on online platforms. From regular fill-in/ fill-up registration forms to complex quiz-like structures or games, everything can be quickly developed with JSP’s help.
This has been a guide to What is JSP? Here we discussed the concepts, working, advantages, disadvantages, and how it helps career growth. You can also go through our other suggested articles to learn more –