How to propagate an exception up the call stack for further processing?

In Java, to propagate an exception up the call stack, the throw keyword is used inside a catch block or simply declaring the method with throws.

Example of propagating an exception from a method:

public void method() throws IOException {
    // code that may throw IOException
    if (someCondition) {
        throw new IOException("Input/output error");
    }
}

public void caller() throws IOException {
    method(); // exception is propagated further
}

If you need to catch and rethrow an exception:

try {
    method();
} catch (IOException e) {
    // additional handling logic can be added
    throw e; // propagate the exception upwards
}

Thus, to pass an exception up the call stack, it must be thrown with throw or declared in the method signature with throws.