Java Interview Guide : 200+ Interview Questions and Answers - Synchronization of Threads: join, wait, notify and notifyA

The video tutorial discusses the challenges of concurrent thread execution, such as data inconsistency and errors. It introduces the synchronized keyword to manage thread access to methods and blocks, ensuring only one thread executes at a time. The tutorial also covers thread management techniques like join and yield, explains deadlocks, and demonstrates inter-thread communication using wait and notify methods. A practical example is provided to illustrate these concepts in action.

What problem can occur when two threads access shared resources concurrently?

• The program runs faster.

• The threads execute in sequence.

• Unexpected results due to thread interference.

• The program becomes more efficient.

What does the synchronized keyword do in Java?

• Ensures only one thread can execute a method at a time.

• Speeds up the execution of a method.

• Prevents any thread from executing a method.

• Allows multiple threads to execute a method simultaneously.

How does synchronization of static methods differ from instance methods?

• It is at the instance level, not the class level.

• It does not differ at all.

• It is at the class level, not the instance level.

• It allows multiple threads to execute simultaneously.

What is the purpose of the join method in thread coordination?

• To run two threads simultaneously.

• To stop a thread immediately.

• To make a thread wait for another to complete.

• To start a new thread.

What happens when a thread calls the yield method?

• It increases its priority.

• It terminates immediately.

• It goes to sleep indefinitely.

• It suggests the scheduler to switch to another thread.

What is a deadlock in the context of threads?

• A situation where threads never start.

• A situation where threads execute in sequence.

• A situation where threads wait indefinitely for each other.

• A situation where threads run faster.

Which methods are used for inter-thread communication in Java?

• begin, end, and halt

• start, stop, and pause

• run, execute, and finish

• wait, notify, and notifyAll