java - Is there a difference between int[] b = new int[a.length] b=a and int[] b = a? -

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is there difference between 

int[] b = new int[a.length]; b=a;

and

int[] b = a;

in java?

they're same, there few differences:

  • in general, first 1 create array becomes unreachable (eligible garbage collection), not exist. (in both versions, b ends referring same array a, aside caveats below.)
  • if a null, first 1 throw nullpointerexception.
  • if you're unlucky, first 1 throw outofmemoryerror or similar.
  • the first 1 more cause compiler warnings, findbugs warnings, etc.

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