Java Interview Guide : 200+ Interview Questions and Answers - Creating Custom Exceptions

The video tutorial covers the creation and handling of custom exceptions in Java, distinguishing between checked and unchecked exceptions. It discusses best practices for exception handling, including the use of try with resources introduced in Java 7. The tutorial emphasizes the importance of global exception handling and provides examples to illustrate these concepts.

What is the main difference between a checked and an unchecked exception in Java?

• Checked exceptions must be declared or handled, while unchecked exceptions do not.

• Unchecked exceptions must be declared or handled, while checked exceptions do not.

• Checked exceptions are only used for runtime errors.

• Unchecked exceptions are only used for compile-time errors.

How can you create a custom checked exception in Java?

• By using the throws keyword.

• By extending the Exception class.

• By implementing the Serializable interface.

• By extending the RuntimeException class.

Why is it important to order catch blocks from specific to general exceptions?

• To ensure that the most specific exception is caught first.

• To avoid compilation errors.

• To improve the performance of the program.

• To make the code more readable.

How can you handle multiple exception types in a single catch block in Java 7 and later?

• By using a switch statement.

• By using a try-catch-finally block.

• By nesting try blocks.

• By using a multi-catch block with the 'or' operator.

What is the main advantage of using try-with-resources in Java?

• It allows for multiple catch blocks.

• It automatically closes resources, reducing boilerplate code.

• It improves the performance of the program.

• It allows for nested try blocks.

Which interface must a resource implement to be used in a try-with-resources statement?

• AutoCloseable

• Serializable

• Cloneable

• Runnable

Why should exceptions not be used for flow control in a program?

• They have a significant performance impact.

• They make the code harder to read.

• They can lead to security vulnerabilities.

• They are too slow for this purpose.

What should be considered when deciding between a checked and an unchecked exception?

• Whether the calling method can handle the exception.

• The version of Java being used.

• The size of the codebase.

• The number of developers on the team.

What is a key benefit of having global exception handling in a multi-layered application?

• It simplifies the code structure.

• It reduces the need for exception handling in each layer.

• It improves the application's performance.

• It allows for more specific error messages.

In what scenario is it better to use an unchecked exception over a checked exception?

• When the exception is related to network operations.

• When the calling method cannot do anything about the exception.

• When the exception is related to file operations.

• When the exception is related to user input.