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Why is the java.util.Scanner class declared "final"?

I use the scanner class to read several similar files. I would like to expand it to make sure that they all use the same separator, and I can also add methods like skipUntilYouFind (String thisHere) that they are all valid for everyone.

I can make a utility class that contains them, or insert the scanner class as a variable inside another class, but this is more cumbersome.

I found some reasons to declare the final class, but why is this done here?

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3 answers

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public boolean nextBoolean()  {
    clearCaches();
    return Boolean.parseBoolean(next(boolPattern()));
}

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I saw many implementations that used inheritance to change behavior. The end result was usually a monolithic design, and in some cases a broken contract and / or violation of behavior.

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