As a long-time Java developer, I absolutely abhor the assumption that everything can be safely subclassed and overridden unless it is explicitly declared as final.
Implementation inheritance breaks encapsulation. It creates an intimate entanglement between the internal implementation details of the super- and sub-classes. Every time you extend a class or override a method that wasn't explicitly and carefully designed to be subclassed and overridden safely, you are _writing hacky code_.
There are, of course, places for hacky code. If you understand why something is hacky and feel it's a worthwhile trade-off then by all means you should be able to do it. Java, though, encourages people to pepper their code with such hacks before they have learned why they shouldn't.
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As a long-time Java developer, I absolutely abhor the assumption that everything can be safely subclassed and overridden unless it is explicitly declared as final.
Implementation inheritance breaks encapsulation. It creates an intimate entanglement between the internal implementation details of the super- and sub-classes. Every time you extend a class or override a method that wasn't explicitly and carefully designed to be subclassed and overridden safely, you are _writing hacky code_.
There are, of course, places for hacky code. If you understand why something is hacky and feel it's a worthwhile trade-off then by all means you should be able to do it. Java, though, encourages people to pepper their code with such hacks before they have learned why they shouldn't.