Chapter 12: Problem 18

If a method has a throw statement, does it always have to have a throws clause in its header? Why or why not?

Short Answer

Expert verified

Short Answer: A method containing a throw statement does not always need to have a throws clause in its header, as it depends on whether the exception is checked or unchecked. If the exception is checked, a throws clause is required unless enclosed in a try-catch block, while it is not needed for unchecked exceptions.

Step by step solution

Understanding Checked and Unchecked Exceptions

In Java, exceptions are categorized into two types: checked and unchecked exceptions. Checked exceptions are the exceptions that are checked by the compiler at compile-time. Unchecked exceptions are those that occur during runtime and are not checked by the compiler.

Checked Exceptions and throws clause

When a method has the potential to throw a checked exception, it must include a throws clause in its header. This is because the compiler checks for proper handling of checked exceptions. To handle a checked exception in a method, one of the following must be done: 1. Enclose the code that may throw the exception in a try-catch block. 2. Declare the exception in the method's header using the throws clause. If the method has a throw statement for a checked exception, it must have a throws clause in its header, except when the throw statement is enclosed in a try-catch block. This alerts the calling method that this exception should be handled or propagated further up the call stack.

Unchecked Exceptions and throws clause

In the case of unchecked exceptions, the compiler does not require the method to have a throws clause in its header, even if the method contains a throw statement. Unchecked exceptions are usually caused by programmer errors, such as accessing an index out of bounds or trying to access a null object. These exceptions are subclasses of RuntimeException and can be handled in a try-catch block, but it is not mandatory.

Conclusion

A method with a throw statement does not always need to have a throws clause in its header. If the throw statement is for a checked exception, then it must have a throws clause, except when the statement is enclosed in a try-catch block. For unchecked exceptions, a throws clause is not required. In general, it's essential to properly handle exceptions to ensure robust and fault-tolerant code.

Unlock Step-by-Step Solutions & Ace Your Exams!

Full Textbook Solutions
Get detailed explanations and key concepts
Unlimited Al creation
Al flashcards, explanations, exams and more...
Ads-free access
To over 500 millions flashcards
Money-back guarantee
We refund you if you fail your exam.

Start your free trial

Over 30 million students worldwide already upgrade their learning with Vaia!

Recommended explanations on Computer Science Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

If a method has a throw statement, does it always have to have a throws clause in its header? Why or why not?

Short Answer

Step by step solution

Understanding Checked and Unchecked Exceptions

Checked Exceptions and throws clause

Unchecked Exceptions and throws clause

Conclusion

One App. One Place for Learning.

Most popular questions from this chapter

Recommended explanations on Computer Science Textbooks

Functional Programming

Data Structures

Computer Programming

Data Representation in Computer Science

Theory of Computation

Databases

Study anywhere. Anytime. Across all devices.