JAVA SERVLET PROGRAMS

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Servlet Advantages and Disadvantages

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Session Management

What is a session? A session is pretty much what it sounds, when a user makes a page request to the server, the server creates a temporary session to identify that user. So when that same user goes to another page on that site, the server identifies that user. So a session is a small and temporary unique connection between a server and the user enabling it to identify that user across multiple page requests or visits to that site. Why should a session be maintained? When there is a series of continuous request and response from a same client to a server, the server cannot identify from which client it is getting requests. Because HTTP is a stateless protocol. When there is a need to maintain the conversational state, session tracking is needed. For example, in a shopping cart application a client keeps on adding items into his cart using multiple requests. When every request is made, the server should identify in which client’s cart the item is to be added. So in this sc
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The Deployment Descriptor: web.xml

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Before I explain what a deployment descriptor is, we should first understand the web application directory structure WEB APPLICATION DIRECTORY STRUCTURE: A Web application contains a structure hierarchy of directories and files in a standard layout. Such a hierarchy can be accessed in its "unpacked" form, where each directory and file exists in the filesystem separately(This  format is more useful during development) , or in its "packed" WAR file(This format is used  when you distribute your application to be installed) . Any Web Application that is to be deployed in Tomcat has to conform to this directory structure. The format of the structure can be seen in the figure below: Web Application Directory Structure Application Root Directory   - This is the root directory of the Web Application. The name of this directory is named by the developer - for example the default context we created for this module was called "stud
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