Given below is the HelloForm.java servlet program to handle input given by web browser. Here is a simple URL which will pass two values to HelloForm program using GET method. GetParameterNames() − Call this method if you want a complete list of all parameters in the current request. GetParameterValues() − Call this method if the parameter appears more than once and returns multiple values, for example checkbox. GetParameter() − You call request.getParameter() method to get the value of a form parameter. Servlets handles form data parsing automatically using the following methods depending on the situation − Servlet handles this type of requests using doPost() method. This message comes to the backend program in the form of the standard input which you can parse and use for your processing. Create a bean file ' LoginBean.java ' to mapping the parameter from ' loginbean.jsp '. Create a webpage ' loginbean.jsp ' to set the parameter using JSP Bean and forward to the Servlet page. This packages the information in exactly the same way as GET method, but instead of sending it as a text string after a ? (question mark) in the URL it sends it as a separate message. Create a webpage ' login.jsp ' to login the user. POST MethodĪ generally more reliable method of passing information to a backend program is the POST method. This information is passed using QUERY_STRING header and will be accessible through QUERY_STRING environment variable and Servlet handles this type of requests using doGet() method. The GET method has size limitation: only 1024 characters can be used in a request string.

Never use the GET method if you have password or other sensitive information to pass to the server. When user information passed in a form, it is validated with the record saved into the database table. The GET method is the default method to pass information from browser to web server and it produces a long string that appears in your browser's Location:box. This login page example was developed using Servlet, JSP, and MySQL(MariaDB) database connectivity. The page and the encoded information are separated by the ? (question mark) symbol as follows − The GET method sends the encoded user information appended to the page request. These methods are GET Method and POST Method. The browser uses two methods to pass this information to web server. You must have come across many situations when you need to pass some information from your browser to web server and ultimately to your backend program.

Servlet program for a login page