What does thread-safe mean in the context of servlets?
- It means a servlet can handle multiple requests concurrently without any issues.
- It means a servlet can only handle one request at a time.
- It means a servlet cannot handle multiple requests.
- It means a servlet is immune to threading issues.
In the context of servlets, "thread-safe" means that a servlet can handle multiple requests concurrently without encountering threading issues.
Which method should be overridden to make a servlet thread-safe without synchronizing the entire service method?
- destroy()
- doPost()
- init()
- service()
To make a servlet thread-safe without synchronizing the entire service method, you should override the service() method and implement thread safety measures within it.
What is the risk of having instance variables in a servlet?
- Instance variables are mandatory in servlets.
- Instance variables can be accessed by multiple threads concurrently, leading to potential threading issues.
- Instance variables increase servlet performance.
- There is no risk.
The risk of having instance variables in a servlet is that they can be accessed by multiple threads concurrently, potentially causing threading issues.
How does the Servlet container typically handle concurrent requests to the same servlet?
- By creating a new instance of the servlet for each request
- By creating a new thread for each request
- By queuing the requests and processing them sequentially
- By using a single shared instance of the servlet
The Servlet container typically handles concurrent requests by using a single shared instance of the servlet, allowing multiple threads to access the same instance concurrently.
What is the impact of synchronization on servlet performance?
- Degrades performance
- Enhances scalability
- Improves performance
- No impact on performance
Synchronization can degrade servlet performance due to increased contention for locks. It's essential to use synchronization judiciously to prevent performance bottlenecks.
When handling a file upload, if an IOException occurs, how should the servlet respond and log the event?
- Ignore the exception
- Print the exception stack trace
- Send an appropriate HTTP error code
- Terminate the servlet
When an IOException occurs during a file upload, the servlet should send an appropriate HTTP error code to inform the client about the issue, and the event should be logged for troubleshooting and debugging purposes.
How can a server control the lifetime of a cookie in a client's browser?
- Setting the Domain attribute
- Setting the Expires attribute
- Setting the Max-Age attribute
- Setting the Path attribute
The server can control the lifetime of a cookie by setting the Max-Age attribute, specifying the maximum age of the cookie in seconds.
Which of the following is a common practice for ensuring thread safety in servlets?
- Avoiding the use of static variables
- Releasing all resources in the destroy() method
- Synchronization of the service() method
- Using a single shared resource in the servlet
A common practice for ensuring thread safety in servlets is avoiding the use of static variables, as they can lead to conflicts when multiple threads are accessing the servlet concurrently.
When is it necessary to consider thread safety in the development of a servlet?
- Always, whenever the servlet is handling concurrent requests
- Only when the servlet is handling file uploads
- When the servlet has static variables
- When the servlet is used in a single-threaded environment
It is necessary to consider thread safety in the development of a servlet whenever the servlet is handling concurrent requests to ensure that multiple threads can access the servlet without causing conflicts or data corruption.
How can you avoid concurrency issues in a servlet without using synchronization?
- Implement single-threaded model
- Optimize database queries
- Use synchronized blocks
- Use volatile variables
Concurrency issues can be avoided by implementing a single-threaded model where a servlet processes one request at a time, eliminating the need for synchronization.