What is session tracking in the context of servlets?
- Handling HTTP requests
- Maintaining user sessions
- Managing servlet lifecycle
- Processing form data
Session tracking in servlets involves maintaining user sessions, allowing the server to recognize and remember users across multiple requests, usually achieved through mechanisms like cookies or URL rewriting.
If a servlet needs to access a shared resource specified in the web application's context parameters, which approach should be used?
- Access the shared resource through the HttpSession object.
- Directly access the shared resource using the File class.
- Use a global variable within the servlet to store the shared resource.
- Utilize the ServletContext to retrieve the shared resource using getInitParameter().
To access a shared resource specified in the web application's context parameters, a servlet should use the ServletContext and the getInitParameter() method. This ensures proper retrieval of the shared resource.
The __________ method is called to allow the servlet to respond to a request.
- destroy()
- doGet()
- init()
- service()
The service() method is called to allow the servlet to respond to a request. It handles the actual processing of the request.
A servlet needs to read its own initialization parameters and also share a database connection pool. Which combination of objects should it use?
- getInitParameter() and ServletContext
- getServletConfig() and getServletContext()
- getServletContext() and getInitParameter()
- getServletContext() and getInitParameter()
To read its own initialization parameters, a servlet should use getInitParameter(). To share a database connection pool, it should use the ServletContext, which is accessible via getServletContext().
To set multiple values for the same header, use the __________ method in HttpServletResponse.
- addHeader()
- appendHeader()
- setHeader()
- setMultipleValuesHeader()
The addHeader() method in HttpServletResponse is used to add multiple values for the same header, allowing for flexibility in handling headers with multiple values.
In which method of a servlet are most of the resources like threads, database connections, etc., released?
- destroy()
- doGet()
- init()
- service()
The destroy() method is called when a servlet is being removed from service, and it is used to release resources like threads and database connections.
When using RequestDispatcher's forward method, changes to the response _________ affect the final output.
- always
- may
- will
- will not
When using RequestDispatcher's forward method, changes to the response will not affect the final output, as the forward method transfers control without changing the response.
The method __________ of the HttpServletRequest is used to read binary data from a form input.
- getBinaryData()
- getInputStream()
- readBinaryData()
- readFormData()
The getInputStream() method of the HttpServletRequest is used to read binary data from a form input.
To prevent character encoding issues when reading form data, the method __________ should be called before any getParameter methods.
- encodeCharacters
- handleEncoding
- resolveCharacterIssues
- setCharacterEncoding
To prevent character encoding issues when reading form data, the setCharacterEncoding method should be called before any getParameter methods. This ensures correct interpretation of characters in the form data.
How does session tracking differ between stateless and stateful protocols?
- Stateful: Lightweight
- Stateful: Stores client state
- Stateless: No memory of previous requests
- Stateless: Uses cookies
Stateless protocols, like HTTP, have no memory of previous requests, while stateful protocols, like HTTPS, store client state, allowing continuity across multiple requests.
What method of the HttpServletRequest object is used to retrieve a form parameter by name?
- fetchParameter(String name)
- getFormParameter(String name)
- getParameter(String name)
- retrieveParameter(String name)
The getParameter(String name) method is used to retrieve a form parameter by name from the HttpServletRequest object.
Which method is used to retrieve a servlet's initialization parameter in the servlet code?
- getInitParam()
- getServletConfig().getInitParameter()
- getServletContext().getInitParam()
- request.getParameter()
The method getServletConfig().getInitParameter() is used to retrieve a servlet's initialization parameter in the servlet code.