throw exception return java code example

Example 1: throw io exception java

public static void foo() throws IOException {
    // some code here, when something goes wrong, you might do:
    throw new IOException("error message");
}

public static void main(String[] args) {
    try {
        foo();
    } catch (IOException e) {
        System.out.println(e.getMessage());
    }
}

Example 2: in java how to throw exception from function

public void doChangePin(int oldPin, int pin) throws Exception {	//need to add throws followed by exception name
		if (oldPin == pinCode) {
			pinCode = pin;
		} else {
			throw new Exception("some message");	//throwing the exception by creating its new object
		}
	}