How compiler is knowing that which type of exception is occurring?

When an exception occurs in your program, catch blocks are examined sequentially from top to bottom to find a match between the type of exception occurred and the type of the exception that the catch block is handling.

How does Java handle checked and unchecked exceptions?

A checked exception must be handled either by re-throwing or with a try catch block, whereas an unchecked isn’t required to be handled. A runtime exception is a programming error and is fatal whereas a checked exception is an exception condition within your code’s logic and can be recovered or re-tried from.

How compiler Will knows about checked exception?

A compiler for the Java programming language checks, at compile time, that a program contains handlers for checked exceptions, by analyzing which checked exceptions can result from execution of a method or constructor. For each checked exception which is a possible result, the throws clause for the method (§8.4.

Which of the following are checked exceptions in Java?

Some common checked exceptions in Java are IOException, SQLException and ParseException.

What are the checked exceptions in Java?

Checked Exceptions For example, the constructor of FileInputStream throws FileNotFoundException if the input file does not exist. Java verifies checked exceptions at compile-time. Some common checked exceptions in Java are IOException, SQLException and ParseException.

How exceptions are propagated in Java?

Exception propagation in Java occurs when an exception thrown from the top of the stack. When it is not caught, the exception drops down the call stack of the preceding method. If it is not caught there, it further drops down to the previous method.

Does exception propagated automatically in Java?

Whenever methods are called stack is formed and an exception is first thrown from the top of the stack and if it is not caught, it starts coming down the stack to previous methods until it is not caught. unchecked exceptions are automatically propagated in java.

What is the difference between checked and unchecked exceptions in Java?

In Java, the direct parent class of Unchecked Exception RuntimeException. Unlike the checked exceptions, the compiler generally ignores the unchecked exceptions during compilation. Unchecked exceptions are checked during the runtime. Therefore, the compiler does not check whether the user program contains the code to handle them or not.

What happens if the compiler does not handle the unchecked exceptions?

The compiler will never give an error if the code does not handle the unchecked exceptions. They are the direct subclass of the Exception class. JVM needs to catch and handle the checked exception. JVM needs not catch and handle the unchecked exception. Checked Exceptions mainly occur when the chances of failure are too high.

How does the Java compiler check for errors during compilation?

The Java compiler checks the checked exceptions during compilation to verify that a method that is throwing an exception contains the code to handle the exception with the try-catch block or not. And, if there is no code to handle them, then the compiler checks whether the method is declared using the throws keyword.

What is the difference between a checked exception and compilation error?

And, if the compiler finds neither of the two cases, then it gives a compilation error. A checked exception extends the Exception class. For example, if we write a program to read data from a file using a FileReader class and if the file does not exist, then there is a FileNotFoundException.