What is Java Servlet?
The Java servlet is basically a program in Java which is designed to extend its capabilities. It can respond to varied requests and usually runs applications which are hosted on servers. These servlets are therefore Java counterparts to dynamic Internet-content technologies like the ASP.NET and PHP. The Java servlet is a server-side program module which can process and respond to client requests and executes a servlet interface. In short, it can help to improve the functions of web servers with very less overhead and maintenance.
How does the Java servlet work?
The Java servlet works like an intermediary between server and client; so just as regular servlet modules operate on servers, these can also respond to client queries. They can handle HTTP requests and then send the information back to clients. Because a servlet is incorporate with Java language, it naturally possesses all features of Java like security, platform independence, high portability and database connectivity. Java servlets can be two types namely Basic and HTTP.
When HTML forms are submitted, this servlet will process and store the data. When clients provide database related queries, results are sent to them by the servlet. The server typically makes use of the CGI or Common Gateway Interface. But the Java servlet is known to have distinct advantages over the CGI such as:
– The servlet will operate in the same procedure and you do not need to create new processes for each request made.
– The CGI program must be reloaded each time for a CGI request. The servlet requires no reloading at all and can stay in the memory in between the requests.
– The servlet uses a single instance to answer many queries and requests and this helps to save data and manage persistent data.
– The servlet operates in a restricted environment which protects the server from other harmful servlets.
The Java servlet is becoming very popular these days compared to CGI programs because this applet is persistent and once started will be retained in the memory to satisfy multiple requests. In contrast, the CGI program will vanish after fulfilling a request. This makes Java servlets faster and you do not waste precious time installing and uninstalling the process. The servlets will also generate dynamic content which are easy to create and quicker to execute within web servers. The servlets are component based and platform independent applications and are not limited by performance limitations like the CGI. Servlets enjoy multiple advantages like efficiency, portability, security, extensibility, affordability etc. They are very portable across operating systems since they have written in Java and abide by standard APIs.