How would a filter log request information without altering the request itself?
- Use a separate logging library
- Use a wrapper around the ServletResponse
- Use response.getWriter().write()
- Use response.log() method
To log request information without altering the response, a filter can use a wrapper around the ServletResponse. This allows capturing the response data without modifying it.
Which component in a Java EE application is responsible for managing connection pooling?
- Connection Pool
- Enterprise JavaBeans (EJB)
- JDBC Driver
- Servlet Container
Connection pooling is typically managed by a dedicated component known as the connection pool, which handles the creation, management, and recycling of database connections in a Java EE application.
When a connection is closed in a connection pool, what actually happens to that connection?
- It is immediately returned to the pool
- It is marked as unavailable
- It is permanently deleted
- It is physically closed
When a connection is closed in a connection pool, it is not physically closed but rather returned to the pool, making it available for reuse. This enhances efficiency by minimizing the need for new connections.
How does connection pooling improve the performance of database-driven applications?
- Caches database queries
- Has no impact on database connections
- Increases the number of open database connections
- Reduces the number of open database connections
Connection pooling improves performance by reducing the number of open database connections, reusing existing ones, and avoiding the overhead of opening and closing connections frequently.
What role does the JDBC API play in connection pooling?
- Deals with servlet lifecycle
- Handles SQL queries
- Manages database connections
- Provides database authentication
The JDBC API is responsible for managing database connections in connection pooling, ensuring efficient utilization and reuse of connections in a database-driven application.
How does a servlet container typically interact with a connection pool?
- It delegates management to the application.
- It directly manages the pool.
- It doesn't interact with connection pools.
- It relies on the database server for connection management.
In a typical scenario, a servlet container directly manages the connection pool, ensuring efficient utilization and management of database connections within the application.
During peak usage, a web application's response time degrades significantly. Which connection pool setting should be investigated?
- Connection Timeout
- Max Connections Per Partition
- Min Pool Size
- Partition Count
To address degraded response time during peak usage, investigate the Max Connections Per Partition setting, which controls the maximum number of connections allowed in each partition.
What is the primary advantage of using a PreparedStatement in JDBC?
- PreparedStatements are faster than Statement objects.
- PreparedStatements are used for executing stored procedures.
- PreparedStatements help prevent SQL injection attacks.
- PreparedStatements require a connection pool.
PreparedStatements are precompiled SQL statements that are faster than Statement objects, providing better performance in JDBC operations.
What is a common strategy for handling the situation when all connections in the pool are in use?
- Automatically create more connections
- Ignore the situation
- Terminate the application
- Wait for a connection to become available
Waiting for a connection to become available is a common strategy, ensuring that the application doesn't crash when all connections in the pool are in use.
What is the impact of setting a very high or very low size for the connection pool?
- Both high and low sizes have a negative impact on performance.
- High size can lead to resource wastage, while low size may cause performance issues.
- High size improves performance, but low size reduces resource usage.
- Setting size doesn't affect performance.
Setting a very high size for the connection pool can lead to resource wastage, while a very low size may cause performance issues. It's essential to find an optimal size to balance performance and resource usage effectively.