Can a Catch Block in a Subclass Handle Checked Exceptions from a Parent Class?

Can a Catch Block in a Subclass Handle Checked Exceptions from a Parent Class?

In Java, checked exceptions are exceptions that must be either caught or declared in the method signature. When dealing with inheritance, it's important to understand how catch blocks in subclasses interact with checked exceptions thrown by parent classes. This explanation clarifies whether a subclass's catch block can catch checked exceptions defined in its parent class and provides insights into best practices.

try {
    parentClassMethod(); // This may throw a checked exception
} catch (CheckedException e) {
    // Handle checked exception
} catch (AnotherCheckedException e) {
    // Handle another type of checked exception
}

Causes

• Checked exceptions are part of the method signature of a class that might throw them.
• A subclass inherits the methods of its parent class, including exceptions defined in the method signatures.

Solutions

• A subclass's catch block can catch checked exceptions if it explicitly declares them or if they are part of the method's broader exception handling.
• Ensure that the catch block in the subclass handles the specific exception type or its supertype.

Mistake: Failing to declare checked exceptions in overridden methods.

Solution: Always include the checked exceptions in the method signature if those are thrown by the parent class.

Mistake: Assuming that a subclass can handle any checked exception without declaring it.

Solution: Recognize that only exceptions declared in the method signature can be caught unless handled through a superclass reference.