WorkVentures Interview Questions and Answers

Fill ratio is the percentage of array slots that are occupied by elements. Concurrency level is the estimated number of concurrently updating threads.

• Fill ratio is important for performance optimization and memory usage.

• Concurrency level determines the number of segments in the collection.

• Higher concurrency level can improve performance but also increases memory usage.

• Examples of concurrent collection frameworks include ConcurrentHashMap and ConcurrentLinkedQueue.

HashMap is a data structure that stores key-value pairs and provides constant time complexity for basic operations.

• HashMap uses hashing to store and retrieve values based on their keys.

• It allows null values and one null key.

• Collisions are resolved by chaining or open addressing.

• The initial capacity and load factor can be specified during initialization.

• The internal array is resized when the load factor exceeds a threshold.

• The put() method adds a key-value pair to the map.

• The ...read more

StringBuffer is synchronized while StringBuilder is not.

• StringBuffer is thread-safe while StringBuilder is not.

• StringBuffer is slower than StringBuilder due to synchronization.

• StringBuilder is preferred for single-threaded operations.

• Both classes are used for manipulating strings.

• Example: StringBuffer sb = new StringBuffer(); StringBuilder sb = new StringBuilder();

Encapsulation is the process of hiding implementation details and exposing only necessary information.

• Encapsulation is achieved through access modifiers like public, private, and protected.

• It helps in achieving data abstraction and information hiding.

• It prevents unauthorized access to the internal details of an object.

• Example: A class with private variables and public methods to access those variables.

• Example: A capsule that encloses medicine and only allows access through a ...read more

The entry point of a Java program, must be public, static, void and accept an array of strings as argument.

• public: accessible from anywhere in the program

• static: belongs to the class, not to an instance of the class

• void: does not return any value

• main: the name of the method that serves as the entry point of the program

• String[] args: an array of strings that can be used to pass arguments to the program