Differences between throw and throws in java

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In this post we will be discussing differences between throw and throws

Differences between throw and throws in java >

	throw	throws
1	throw keyword is used to throw an exception explicitly.	throws keyword is used to declare an exception.
2	throw is used inside method. Example > static void m(){    throw new FileNotFoundException(); }	throws is used in method declaration. Example > static void m() throws FileNotFoundException{ }
3	throw is always followed by instanceof Exception class. Example > throw new FileNotFoundException()	throws is always followed by name of Exception class. Example > throws FileNotFoundException
4	throw can be used to throw only one exception at time. Example > throw new FileNotFoundException()	throws can be used to throw multiple exception at time. Example > throws FileNotFoundException, NullPointerException and many more...
5	throw cannot propagate exception to calling method.	throws can propagate exception to calling method. Please see these programs to understand how exception is propagated to calling method. Program 1 - Handling Exception by throwing it from m() method (using throws keyword) and handling it in try-catch block from where call to method m() was made. Program 2 - Throwing Exception from m() method and then again throwing it from calling method [ i.e. main method]

Similarities between throw and throws in java >

Though there are not much similarities between two, but both are keywords in java.

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Labels: Core Java Exception Differences and Similarities Exceptions