#Exception handling

Question count - 0     Last updated    - V4 (07-Aug-2024)

What is an Exception in Java?

What are the Exception Handling Keywords in Java?

Explain Java Exception Hierarchy?

What are the important methods of Java Exception Class?

Explain Java 7 ARM Feature and multi-catch block?

What is the difference between Checked and Unchecked Exceptions in Java?

What is the difference between the throw and throws keyword in Java?

How to write custom exceptions in Java?

What are different scenarios causing ?Exception in thread main??

What is the difference between final, finally, and finalize in Java?

What happens when an exception is thrown by the main method?

Can we have an empty catch block?

What is NullPointerException?

What is ArrayIndexOutOfBoundsException?

What is NumberFormatException?

How the exceptions are handled in java? OR Explain exception handling mechanism in java?

What is try block?

What is catch block?

What is finally block?

What is an exception?

What is the difference between error and exception in java?

What is unreachable catch block error?

What are run time exceptions in java. Give example?

What is OutOfMemoryError in java?

what are checked and unchecked exceptions in java?

What is the difference between ClassNotFoundException and NoClassDefFoundError in java?

What is Re-throwing an exception in java?

What is the use of throws keyword in java?

What is the difference between final, finally and finalize in java?

What is ClassCastException in java?

What is the difference between throw, throws and throwable in java?

What is StackOverflowError in java?

What are chained exceptions in java?

What are the legal combinations of try, catch and finally blocks?

What is the use of printStackTrace() method?

What is ClassNotFoundException?

What is SQLException?

What is IOException

Explain the hierarchy of exceptions in java?

Why it is always recommended that clean up operations like closing the DB resources to keep inside a finally block?

Which class is the super class for all types of errors and exceptions in java?

How the exceptions are handled in java? OR Explain exception handling mechanism in java?

How do you create customized exceptions in java?

Can we keep other statements in between try, catch and finally blocks?

Can we write only try block without catch and finally blocks?

Can we keep the statements after finally block If the control is returning from the finally block itself?

Can we throw an exception manually? If yes, how?

Can we override a super class method which is throwing an unchecked exception with checked exception in the sub class?

Does finally block get executed If either try or catch blocks are returning the control?

Give some examples to checked exceptions?

Give some examples to unchecked exceptions?

What is Exception Handling in Java?

Differentiate between Checked and Unchecked Exceptions.

What are the core components of Java's exception handling mechanism?

Explain the try-catch-finally block in Java.

Can finally block be skipped?

What are the advantages of using finally block?

What is the purpose of the throws keyword?

Can you rethrow an exception in Java?

How do you handle multiple exceptions in Java?

What is the difference between throw and throws in Java?

Explain the concept of Custom Exceptions.

What are the best practices for exception handling in Java?

What design pattern is used to implement exception handling features in most languages?

What is the need for finally block?

What is the difference between error and exception?

What is the difference between checked exceptions and unchecked exceptions?

What happens when you throw a checked exception from a method?

What are the options you have to eliminate compilation errors when handling checked exceptions?

Why is exception handling important?

How do you throw an exception from a method?

How do you create a custom exception?

How do you handle multiple exception types with same exception handling block?

How does try with resources work?

In what scenarios is code in finally not executed?

Will finally be executed in the program below?

Exception	It is one of the powerful mechanism to handle the runtime errors The java.lang.Throwable class is the root class of Java Exception hierarchy which is inherited by two subclasses: Exception and Error.
Types	Checked Exception The classes which directly inherit Throwable class except RuntimeException and Error are known as checked exceptions e.g. IOException, SQLException etc. Checked exceptions are checked at compile-time. Unchecked Exception The classes which inherit RuntimeException are known as unchecked exceptions e.g. ArithmeticException, NullPointerException, ArrayIndexOutOfBoundsException etc. Unchecked exceptions are not checked at compile-time, but they are checked at runtime.
Misc	Error - It is irrecoverable e.g. OutOfMemoryError, VirtualMachineError, AssertionError etc. try - It is used to specify a block where we should place exception code. The try block must be followed by either catch or finally. It means, we can't use try block alone. catch - It is used to handle the exception. It must be preceded by try block which means we can't use catch block alone. It can be followed by finally block later. finally - It is used to execute the important code of the program. It is executed whether an exception is handled or not. throw - It is used to throw an exception. throws - It is used to declare exceptions. It doesn't throw an exception. It specifies that there may occur an exception in the method. It is always used with method signature.
Example	ArithmeticException - It is thrown when an exceptional condition has occurred in an arithmetic operation. ArrayIndexOutOfBoundsException - It is thrown to indicate that an array has been accessed with an illegal index. The index is either negative or greater than or equal to the size of the array. ClassNotFoundException - This Exception is raised when we try to access a class whose definition is not found FileNotFoundException - This Exception is raised when a file is not accessible or does not open. IOException - It is thrown when an input-output operation failed or interrupted InterruptedException - It is thrown when a thread is waiting , sleeping , or doing some processing , and it is interrupted. NoSuchFieldException - It is thrown when a class does not contain the field (or variable) specified NoSuchMethodException - It is thrown when accessing a method which is not found. NullPointerException - This exception is raised when referring to the members of a null object. Null represents nothing NumberFormatException - This exception is raised when a method could not convert a string into a numeric format. RuntimeException- This represents any exception which occurs during runtime. StringIndexOutOfBoundsException - It is thrown by String class methods to indicate that an index is either negative than the size of the string

Exception_Handling
Question	Option A	Option B	Option C	Option D
TreeSet internally uses that one to store elements	HashMap	LinkedHashMap	TreeMap	None of these
In which of the following package Exception class exist?	java.util	java.file	java.io	java.lang

Built-in_Exceptions