What is the significance of the web.xml file in handling servlet errors?
- It configures session handling
- It controls servlet access
- It defines error pages
- It sets servlet timeout
The web.xml file is significant in handling servlet errors as it defines error pages, specifying which HTML or JSP page should be displayed for different HTTP error codes.
How can a servlet differentiate between client errors (like 404) and server errors (like 500)?
- By analyzing the response object
- By checking the servlet context
- By examining the exception type
- By inspecting the request object
A servlet can differentiate between client errors (e.g., 404) and server errors (e.g., 500) by examining the type of exception that occurred, typically accessed through the exception handling mechanism.
Which Java interface is typically used for creating custom log messages in a servlet?
- ServletConfig
- ServletContext
- ServletLogger
- ServletRequest
The ServletContext interface is typically used for creating custom log messages in a servlet, providing methods for logging information that can be accessed across the servlet's entire application context.
_________ is a caching technique where frequently and recently accessed data is prioritized for caching.
- FIFO (First In, First Out)
- LRU (Least Recently Used)
- Optimal Replacement
- Random Replacement
LRU (Least Recently Used) is a caching technique where frequently and recently accessed data is prioritized for caching, aiming to keep the most relevant data in the cache.
The strategy of storing only the differences from the main data set in cache is known as __________ caching.
- Delta
- Differential
- Incremental
- Patch
Differential caching involves storing only the differences (or changes) from the main data set in the cache, reducing storage requirements and improving cache efficiency.
A web application implements a caching layer to reduce database load. Over time, the cache starts serving stale data. What caching strategy should be implemented to resolve this?
- Eviction Policies
- Lazy Loading
- Time-to-Live (TTL) caching
- Write-Through Caching
Implementing Time-to-Live (TTL) caching allows data to be cached for a specific duration, after which it is considered stale and refreshed, resolving the issue of serving stale data over time.
A high-traffic website uses a cache that frequently encounters 'cache churn'. What strategy can be used to minimize this effect?
- Bloom Filters
- Cache Sharding
- Least Recently Used (LRU) Caching
- Write-Behind Caching
Using Least Recently Used (LRU) caching strategy helps minimize cache churn by retaining frequently used items in the cache and discarding the least recently used ones, optimizing cache efficiency for a high-traffic website.
An online content platform uses caching to improve user experience. However, users in different regions report varying latency. What caching approach can be adopted to optimize for all users?
- Content Delivery Network (CDN) Caching
- Local Caching
- Proxy Caching
- Write-Through Caching
Adopting Content Delivery Network (CDN) caching helps optimize user experience for users in different regions by distributing cached content to edge servers, reducing latency and enhancing content delivery speed globally.
A servlet needs to log different levels of messages. Which approach is the most effective?
- Print messages to the console
- Use System.out.println()
- Use a logging framework like Log4j
- Write messages to a file
Using a logging framework like Log4j is the most effective approach for logging in a servlet as it provides flexibility, configurability, and allows logging at different levels.
How can a servlet invalidate a cookie that has been sent to the client?
- By calling response.expireCookie()
- By setting the cookie to null
- By setting the cookie's Max-Age to 0
- By using request.removeCookie()
A servlet can invalidate a cookie by setting its Max-Age attribute to 0, indicating that the cookie has expired, and the client should discard it.