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Exception Handling:



Exception Handling:

An exception/error is an abnormal condition that breaks/disrupts the normal program flow. The abnormal condition occurs at run-time i.e. during code execution.
For example, a C program gets terminated when division by zero is encountered at the run-time as this is not a defined operation and result in run-time error. The other familiar example in case of C-language is that of null pointer exception, which occurs when we try to access a memory location through an un-initialized pointer. The program gets terminated in this case also.
Java has a separate construct for exception/error handling like C++. It is possible to recover from an exception/error at run-time and continue the program exception using the exception-handling construct.
A java exception/error is an object of class Exception/Error or one of its sub-class. JVM creates an object of class Exception/Error or one o         f their sub-class whenever exception/error occurs at the run –time. The exception/error object contains details about the exception/error, which can be accessed using the public methods provided for this purpose.
The are two immediate sub classes of class Throwable:
1.      Error
2.      Exception
Exception is the runtime error. If we have not specified a semi-colon, not declared a variables etc.. Then these all errors at being notified the complier, so these are known as the compile time error
But, if we divide a number by zero, if we access an element in an array outside its bound then an exception is occurred, and this all will occur at the run-time

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