Consider a scenario where a servlet application needs to update client-side widgets in real-time. Which technology would be more efficient: AJAX polling or WebSockets?

  • AJAX polling
  • Both are equally efficient.
  • It depends on the specific use case requirements.
  • WebSockets
WebSockets would be more efficient in real-time updates as they allow for bidirectional communication and eliminate the need for continuous polling, reducing latency and server load.

What happens if the init() method of a Servlet throws an exception?

  • Servlet becomes inactive
  • Servlet continues to initialize
  • Servlet fails to initialize
  • Servlet restarts
If the init() method of a Servlet throws an exception, the servlet fails to initialize, and the servlet container may mark the servlet as unavailable.

A high-frequency trading application needs to send and receive financial data with minimal latency. What WebSocket features make it suitable for this application?

  • Caching and client-side data storage
  • Long polling and server-sent events
  • Multiplexing and low latency
  • Request-response pattern and reliable message delivery
WebSockets, with features like multiplexing and low latency, are suitable for high-frequency trading applications, as they enable efficient, bidirectional communication with minimal delay in data transmission.

What is a common practice to reduce the load on a servlet?

  • Caching
  • Database Connection Pooling
  • Lazy Loading
  • Multithreading
Database Connection Pooling is a common practice to reduce the load on a servlet by efficiently managing and reusing database connections, improving performance.

Which of the following is a recommended approach to handle database connections in servlets?

  • Closing connections after each request
  • Connection pooling
  • Opening new connections for each request
  • Using a singleton connection
Connection pooling is a recommended approach for handling database connections in servlets, as it optimizes resource usage and enhances performance.

Why is it important to close resources like database connections in servlets?

  • All of the above
  • To avoid memory leaks
  • To conserve memory
  • To improve performance
Closing resources like database connections is important to avoid memory leaks and ensure efficient memory usage in servlets.

How does using the PreparedStatement in servlets improve performance?

  • PreparedStatements allow for batch processing.
  • PreparedStatements are precompiled, reducing SQL parsing overhead.
  • PreparedStatements are suitable for handling large datasets.
  • PreparedStatements automatically manage database connections.
Using PreparedStatements in servlets improves performance as they are precompiled, reducing SQL parsing overhead, which leads to better execution speed.

How does the sendRedirect() method communicate the new URL to the client's browser?

  • Via HTTP headers
  • Via HTTP status code
  • Via URL parameters
  • Via server-side cookies
The sendRedirect() method communicates the new URL to the client's browser by sending an HTTP redirect response with the new URL in the HTTP headers.

What is the benefit of implementing the SingleThreadModel interface in servlets?

  • Enhanced concurrent processing.
  • Improved thread safety.
  • Reduced memory consumption.
  • Simplified servlet lifecycle.
Implementing the SingleThreadModel interface in servlets provides improved thread safety by ensuring that only one thread can execute the service method at a time, preventing concurrent access issues.

To optimize performance, a servlet should cache frequently used data in the ________.

  • Database
  • Request
  • ServletContext
  • Session
To optimize performance, a servlet should cache frequently used data in the ServletContext to make it available to all components of the web application.