What is the use of throws io exception in java?

Answer 1

an IOException is any unexpected problem the compiler encounters while attempting to run a program. Possible problems the compiler may encounter are attempting to read from a file that does not exist, write to a file which has an invalid name (a slash or a question mark in the title should do it), or attempting to read the next token in a file when there are no more tokens.

Answer 2

When something throws an IOException, it means that whatever is throwing the exception (perhaps a try{}catch block that reads data from a file) can throw an IOException, for example if the file is not found, corrupted, etc, or when the file is otherwise unable to be read, or any other of a list of issues that can occur with the IO package and it's extensions.

Answer 3

The "throws exception" clause in a method is used to indicate that a function may throw an exception during its execution. This is necessary if one of two conditions exist: 1) the exception might be generated by calling some method within this method that would throw an IOException (notably input/output stream methods), or 2) the method might throw a new IOException as a result of unusual processing conditions that make further execution impossible. A method that does not directly handle an exception will throw this exception to its calling method, which must then either handle the exception or pass it to its calling method, and so on up the execution stack. Exceptions which are thrown up past the top of the execution stack cause a stack trace to be printed and the program to cease execution.