java - Tricking the JVM into casting arrays -

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i'd know there way cast array of supertype , array of subtype. so:

subtype[] subarray = (subtype[])somesupertypearray;

i know @ runtime throws classcastexception. way convert array copy array. in case, copying not option.

can trick jvm beliving cast valid, , bypass class type checks? creating reference array of supertype, through seen subtype array. (possibly facing dangers of unexplainable errors)

if define array like

supertype[] array = {element1, element2}; subtype[] array2 = (subtype[]) array;

it not work, can this:

supertype[] array = new subtype[]{element1, element2}; subtype[] array2 = (subtype[]) array;

you have make sure field array has array of subtype when you're casting it.


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