In Java, throw and throws are used to handle exceptions, but they have different purposes and are used in different contexts.
throw is a keyword that is used to throw an exception explicitly in a method or block of code. It is used to indicate that an exceptional situation has occurred and the program cannot continue executing normally.
For example:
public void divide(int a, int b) {
if(b == 0) {
throw new ArithmeticException(“Division by zero”);
}
int result = a / b;
System.out.println(“Result: ” + result);
}
In this example, if the value of b is 0, the method will throw an ArithmeticException with the message “Division by zero”.
throws is a keyword that is used to declare that a method may throw one or more exceptions. It is used in the method signature to indicate that the method is capable of throwing an exception, but it does not actually throw the exception itself.
For example:
public void readFile(String fileName) throws FileNotFoundException {
// Code to read file
}
In this example, the method readFile may throw a FileNotFoundException, but it is not responsible for handling the exception. Instead, the calling code must handle the exception by using a try-catch block or declaring the exception using the throws keyword in its own method signature.
In summary, throw is used to throw an exception explicitly, while throws is used to declare that a method may throw one or more exceptions. throw is used inside a method or block of code, while throws is used in the method signature.