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papercrane • today at 1:28 PM • 2 replies • view on HN

    new Integer(10) == new Integer(10) // true
Before value classes this would always be false. The only time comparing Integer objects with == could be true is if Integer object was create by going through Integer.valueOf (or obviously if they were the same object reference.) By default the cached values where -127 to 127, but that is tuneable at runtime.

https://github.com/openjdk/jdk/blob/jdk-27%2B27/src/java.bas...

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tsimionescu • today at 1:51 PM

It could also be true if the instances were created through auto-boxing (e.g. arrayList.add(10); arrayList.add(10); arrayList.get(0) == array List.get(1) //would return true, but false if you used 1000 instead of 10).

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jmyeet • today at 2:58 PM

So you've made my point in showing how complex this is because you're incorrect [1][2]:

> By default, Java maintains a cache of Integer objects for values between -128 and +127.

[1]: https://stackoverflow.com/questions/3130311/weird-integer-bo...

[2]: https://dev.to/marzuk16/understanding-integer-caching-in-jav...

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