Podcast
Questions and Answers
What type of exception is an ArrayIndexOutOfBoundsException?
What type of exception is an ArrayIndexOutOfBoundsException?
Which of the following exceptions is a checked exception?
Which of the following exceptions is a checked exception?
What is the purpose of the finally block in a try-catch block?
What is the purpose of the finally block in a try-catch block?
What is the Throwable class in Java?
What is the Throwable class in Java?
Signup and view all the answers
What happens to the local variables in a try block after an exception is thrown?
What happens to the local variables in a try block after an exception is thrown?
Signup and view all the answers
What is the difference between a checked and an unchecked exception?
What is the difference between a checked and an unchecked exception?
Signup and view all the answers
What type of exception is a NullPointerException?
What type of exception is a NullPointerException?
Signup and view all the answers
What is the purpose of the catch block in a try-catch block?
What is the purpose of the catch block in a try-catch block?
Signup and view all the answers
What is the superclass of all errors and exceptions in Java?
What is the superclass of all errors and exceptions in Java?
Signup and view all the answers
What is the purpose of the Finally block in a Try-Catch-Finally statement?
What is the purpose of the Finally block in a Try-Catch-Finally statement?
Signup and view all the answers
What is the difference between checked and unchecked exceptions?
What is the difference between checked and unchecked exceptions?
Signup and view all the answers
What is the benefit of using a single Scanner object in a project?
What is the benefit of using a single Scanner object in a project?
Signup and view all the answers
What is the purpose of the Try block in a Try-Catch-Finally statement?
What is the purpose of the Try block in a Try-Catch-Finally statement?
Signup and view all the answers
What is an example of an exception that might occur in a program?
What is an example of an exception that might occur in a program?
Signup and view all the answers
What is the benefit of using exception handling in a program?
What is the benefit of using exception handling in a program?
Signup and view all the answers
What is the effect of using the final modifier with a class?
What is the effect of using the final modifier with a class?
Signup and view all the answers
What happens to the control after the last catch block is executed?
What happens to the control after the last catch block is executed?
Signup and view all the answers
What is the main difference between a try block and a try statement?
What is the main difference between a try block and a try statement?
Signup and view all the answers
What is the purpose of the finally block in a try-catch-finally statement?
What is the purpose of the finally block in a try-catch-finally statement?
Signup and view all the answers
What is the difference between the throw and throws keywords?
What is the difference between the throw and throws keywords?
Signup and view all the answers
What is the characteristic of a checked exception?
What is the characteristic of a checked exception?
Signup and view all the answers
What is the best practice for catching exceptions?
What is the best practice for catching exceptions?
Signup and view all the answers
What is the purpose of the try-with-resources statement?
What is the purpose of the try-with-resources statement?
Signup and view all the answers
What is an example of an unchecked exception?
What is an example of an unchecked exception?
Signup and view all the answers
What is the primary goal of professional programmers when it comes to exception handling?
What is the primary goal of professional programmers when it comes to exception handling?
Signup and view all the answers
What type of exception should a programmer typically not catch?
What type of exception should a programmer typically not catch?
Signup and view all the answers
What is the purpose of using a TRY…CATCH…FINALLY block?
What is the purpose of using a TRY…CATCH…FINALLY block?
Signup and view all the answers
What is the relationship between the Throwable class and the Exception and Error classes?
What is the relationship between the Throwable class and the Exception and Error classes?
Signup and view all the answers
Why is it important to handle exceptions in a program?
Why is it important to handle exceptions in a program?
Signup and view all the answers
What happens when an exception is thrown in a TRY block?
What happens when an exception is thrown in a TRY block?
Signup and view all the answers
What is the main difference between a checked and an unchecked exception?
What is the main difference between a checked and an unchecked exception?
Signup and view all the answers
What is the correct order of execution in a TRY…CATCH…FINALLY block?
What is the correct order of execution in a TRY…CATCH…FINALLY block?
Signup and view all the answers
What is the main purpose of using the try-catch block in exception handling?
What is the main purpose of using the try-catch block in exception handling?
Signup and view all the answers
Which of the following is a characteristic of a checked exception?
Which of the following is a characteristic of a checked exception?
Signup and view all the answers
What is the purpose of the Throwable class in Java's exception hierarchy?
What is the purpose of the Throwable class in Java's exception hierarchy?
Signup and view all the answers
What happens when an exception is thrown in a try block and not caught by any catch block?
What happens when an exception is thrown in a try block and not caught by any catch block?
Signup and view all the answers
What is the benefit of using a finally block in a try-catch block?
What is the benefit of using a finally block in a try-catch block?
Signup and view all the answers
Which of the following is an example of a runtime exception?
Which of the following is an example of a runtime exception?
Signup and view all the answers
What is the primary difference between a checked and an unchecked exception?
What is the primary difference between a checked and an unchecked exception?
Signup and view all the answers
Why is it a good practice to handle exceptions as close to the source of the exception as possible?
Why is it a good practice to handle exceptions as close to the source of the exception as possible?
Signup and view all the answers
Study Notes
Exceptions
- An exception is a strange event that can potentially make a program fail.
- Exceptions can be handled using TRY…CATCH…FINALLY.
Exceptions Hierarchy
- Throwable: supertype of all exceptions and errors in Java.
- Three subclasses of Throwable:
- Error: system errors, cannot be caught (e.g. OutOfMemoryError).
- Exception: base class for all exceptions in Java, programmers throw and catch exceptions.
- RuntimeException: a runtime programming error, cannot be thrown and caught (e.g. NullPointerException).
Types of Exceptions
- Checked Exceptions: typically caused by conditions that are not under the control of the program, compiler enforces special requirements (e.g. IOException, ClassNotFoundException).
- Unchecked Exceptions: all exception types that are direct or indirect subclasses of RuntimeException, avoidable by bulletproofing your code (e.g. ArrayIndexOutOfBoundsExceptions, ArithmeticExceptions).
Exception Handling
- Try block: specifies the requirement syntax, where the exception can occur.
- Catch block: handles the exception, can rethrow an exception.
- Finally block: always executes when the try block exits, typically used to release resources.
- Catch should be as close to the problem as possible, and place catch blocks from the specific to general.
Throws and Throw
- Throw: used to throw an exception for a method, cannot throw multiple exceptions.
- Throws: used to indicate what exception types may be thrown by a method, can declare multiple exceptions.
Best Practices
- Catch should be as close to the problem as possible.
- Place catch blocks from the specific to general.
- A catch block can rethrow an exception.
- Reuse existing exception classes where possible, but you can create new ones if needed.
- Only the first matching catch executes.
Final Modifier
- With variable: becomes constant.
- With method: cannot be overridden in subclasses.
- With class: cannot be sub-classed.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
This quiz covers the concepts of exceptions in Java, including types of exceptions, exception hierarchy, and error handling. It is ideal for students and programmers learning Java.