class - Does Java keep classes in the memory or just objects? -

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i'm assuming answer obvious, new coding , cannot find clear answer.

here why ask: have "fastball" class in baseball game, has 10 unique sets of data (10 difficulty levels) pitched fastball, , 1 blank set of data. when object constructed class, sets blank set of data 1 of 10 data sets based on difficulty. note, there 1 "fastball" object @ 1 time.

i worried 10 of data sets in class remain in java's memory, though 1 being used. legitimate concern? or object thing kept in memory?

java load class , put permanent generation part of jvm's memory, happen every class ever use in code. part called permanent generation. not need ever worry part, unless using application containers hot deployment.

the objects create kept on different part of memory(actually, different generation), called heap, divided again in different generations. jvm sort objects in way jvm thinks good, , job @ it. objects sorted in generation of short lived objects cleaned more aggressively, while permanent generation doesn't cleaned @ all. garbage collector handle cleaning after no references these objects remain , frees memory used.

as have provided no code, hard how program work.

i worried 10 of data sets in class remain in java's memory, though 1 being used. legitimate concern? or object thing kept in memory?

depends on if keep references these fastball objects. if keep reference 1 fastball object @ time, garbage collector clean unreferenced objects.


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