Check out example codes for "throw io exception java". It will help you in understanding the concepts better.

Code Example 1

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());
    }
}

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