Tribe21 Consultancy Services Interview Questions and Answers

The main difference is that Spring singleton is managed by the Spring container, while Java singleton is managed by the developer.

• Spring singleton is created and managed by the Spring container, while Java singleton is created and managed by the developer.

• Spring singleton is a design pattern used in Spring framework to create a single instance of a class, while Java singleton is a design pattern used in Java to create a single instance of a class.

• Spring singleton is thread-sa...read more

Spring bean scope defines the lifecycle and visibility of a bean in the Spring container.

• Singleton scope: Only one instance of the bean is created and shared across the application.

• Prototype scope: A new instance of the bean is created every time it is requested.

• Request scope: A new instance of the bean is created for each HTTP request.

• Session scope: A new instance of the bean is created for each HTTP session.

• Global session scope: Similar to session scope, but for global HTTP...read more

HashMap is a data structure that stores key-value pairs and uses hashing to provide constant time complexity for basic operations.

• HashMap internally uses an array of linked lists called buckets to store the key-value pairs.

• When a key-value pair is added, the hash code of the key is computed and used to determine the index of the bucket.

• If multiple key-value pairs have the same hash code, they are stored as a linked list in the same bucket.

• To retrieve a value, the hash code of...read more

No

• Singleton is not inherently thread-safe

• Multiple threads can access and modify the singleton instance simultaneously

• To make it thread-safe, synchronization or double-checked locking can be used

• Alternatively, an enum implementation of singleton is inherently thread-safe