When refactoring a servlet to make it more configurable, what changes are made regarding initialization parameters?
- Introduce new initialization parameters
- Keep the existing parameters unchanged
- Remove all initialization parameters
- Replace parameters with hardcoding
In the process of making a servlet more configurable, one typically introduces new initialization parameters rather than removing or replacing existing ones. This allows for greater flexibility without disrupting existing functionality.
If an SQL exception occurs in a method that performs multiple database updates, how should the exception be handled to maintain data integrity?
- Commit all changes made before the exception
- Ignore the exception and continue with the remaining updates
- Log the exception and terminate the transaction
- Rollback all changes made before the exception
When an SQL exception occurs during multiple updates, rolling back all changes made before the exception helps maintain data integrity by ensuring either all updates succeed or none do.
When designing an application that connects to a database, how should SQL exceptions be managed to provide meaningful feedback to the user?
- Display the raw SQL exception message
- Log the exception and display a user-friendly error message
- Show a generic error message to the user
- Terminate the application on exception
To provide meaningful feedback, log the SQL exception for debugging purposes and display a user-friendly error message to the user, avoiding the display of raw SQL exception messages that may expose sensitive information.
The translation of JSP to servlet occurs in the ______ phase.
- Compiling
- Execution
- Initialization
- Parsing
The translation of JSP to servlet occurs in the compiling phase. JSP pages are translated to servlets before they are compiled into bytecode and executed on the server.
In JDBC, what does Statement.setFetchSize(int rows) method influence?
- Database table indexing
- Number of rows fetched at a time
- Query execution timeout
- Transaction isolation level
The setFetchSize(int rows) method in JDBC influences the number of rows fetched at a time from the result set, which can impact the performance and memory usage of the application.
The _________ method is used to retrieve cookies from the request object.
- findCookies()
- getCookies()
- requestCookies()
- retrieveCookies()
The getCookies() method is used to retrieve cookies from the request object in a servlet.
To ensure that database resources are always released, use the __________ block to close connections.
- catch
- finally
- release
- try
To ensure that database resources are always released, use the finally block to close connections.
In a scenario where a transaction involves multiple SQL queries, how should exceptions be handled to ensure that either all queries succeed or none do?
- Commit each query individually
- Commit the entire transaction only if all queries succeed
- Ignore exceptions and continue with the transaction
- Rollback the entire transaction on any exception
Handling exceptions in a transaction involving multiple SQL queries requires rolling back the entire transaction on any exception to ensure data consistency鈥攅ither all queries succeed, or none do.
Which method is used to batch multiple SQL statements before sending them to the database?
- execute()
- executeBatch()
- executeQuery()
- executeUpdate()
The executeBatch() method is used to batch multiple SQL statements together before sending them to the database, which can improve performance by reducing the number of round-trips.
What is the primary purpose of using a connection pool in database interactions?
- Ensuring database security
- Managing database connections
- Optimizing SQL queries
- Reducing database load
The primary purpose of using a connection pool is to manage and reuse database connections efficiently, reducing the overhead of opening and closing connections for each database interaction.