The ServletContext is shared across multiple servlets within a __________.
- request
- server
- session
- web application
The ServletContext is shared across multiple servlets within a web application.
Can session tracking be implemented using hidden form fields?
- Depends on the browser
- No
- Possible only in HTTPS
- Yes
Session tracking can be implemented using hidden form fields by including the session identifier in the form, allowing it to be sent back to the server with each form submission.
What is a memory leak in the context of Java programming?
- A memory leak occurs when a program allocates memory but forgets to deallocate it, leading to a gradual reduction in available memory.
- A memory leak occurs when a program deallocates memory properly, ensuring optimal memory usage.
- Memory leaks are intentionally created to enhance program performance.
- Memory leaks only occur in languages other than Java.
A memory leak in Java programming happens when the program allocates memory but forgets to deallocate it, resulting in a gradual reduction in available memory.
How does Java's heap memory management differ from stack memory management?
- Both heap and stack memory are used interchangeably.
- Heap and stack memory are the same in Java.
- Heap memory is used for dynamic memory allocation, and objects are stored in the heap. Stack memory is used for static memory allocation, and method calls and local variables are stored in the stack.
- Stack memory is used for dynamic memory allocation, and objects are stored in the stack. Heap memory is used for static memory allocation, and method calls and local variables are stored in the heap.
In Java, heap memory is used for dynamic memory allocation, and objects are stored in the heap, while stack memory is used for static memory allocation, storing method calls and local variables.
Which HTTP header is commonly used to control cache behavior in web browsers?
- Cache-Control
- Content-Encoding
- Expires
- Last-Modified
The Cache-Control header is commonly used to control cache behavior in web browsers by specifying directives for caching mechanisms in both requests and responses.
Which caching strategy involves storing frequently accessed data in memory for quick retrieval?
- Browser caching
- Database caching
- In-memory caching
- Page caching
In-memory caching involves storing frequently accessed data in the system's memory, enabling quick retrieval and enhancing performance.
What is the primary purpose of caching in web applications?
- To add security
- To design the user interface
- To handle user authentication
- To improve performance
The primary purpose of caching in web applications is to improve performance by storing frequently accessed data and reducing the need to fetch it from the original source repeatedly.
In a high-performance Java application, how should memory management be approached to prevent latency issues?
- Frequent use of finalize method
- Implement lazy loading for classes
- Opt for a large heap size
- Utilize efficient garbage collectors
Utilizing efficient garbage collectors is essential for high-performance applications. Implementing lazy loading, opting for a large heap size, and frequent use of the finalize method can lead to latency issues and should be avoided in performance-sensitive applications.
When implementing a servlet to handle form data from a dynamically generated form with varying field names, what strategy should be employed?
- Ignore dynamic form fields for security
- Iterate through request parameters
- Use fixed field names for all form elements
- Use hidden fields to store dynamic names
The recommended strategy is to iterate through request parameters, allowing dynamic handling of varying field names in a dynamically generated form. This approach ensures that all form data, regardless of field names, can be processed dynamically.
When optimizing memory usage in a Java application, what strategies should be considered?
- Disable JIT compilation
- Disable garbage collection
- Increase object creation
- Use data structures efficiently
Efficient use of data structures is crucial for memory optimization. Disabling garbage collection, increasing object creation, and disabling JIT compilation are not recommended strategies and can negatively impact memory usage.
A Java application experiences 'OutOfMemoryError'. What could be the potential causes and solutions?
- Implement caching mechanisms
- Increase heap size using -Xmx
- Optimize code for memory leaks
- Reduce the number of threads
'OutOfMemoryError' may occur due to memory leaks. Optimizing code, reducing threads, and implementing caching mechanisms are strategies to address this issue. Increasing heap size is a solution but doesn't address the root cause of the problem.
The __________ area in JVM memory is used to store per-class structures.
- Class
- Heap
- Method
- Stack
The Class area in JVM memory is used to store per-class structures, such as class metadata, constants, and static fields.