Understanding TimeUnit

I took a look into TimeUnit and toMillis() method.

 public long toMillis(long paramLong)
 {
    throw new AbstractMethodError();
 }

toMillis() method do nothing other than throw an AbstractMethodError exception.

So, How does toMillis() method convert seconds, minutes, etc to milliseconds?

Each value within TimeUnit overrides it, basically. You never end up calling that implementation, because you never have a reference to an object of type TimeUnit - it's always a subclass representing one of the values.

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