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Does this do a shallow copy or a deep copy?

Answer

Wiki MarkupNo copy at all, it just changes the {{_refPoint}} variable to reference the passed in array, and presumably eventually garbage collects the old {{double\[3\]}}. This is not in general a good idea, because the code may not behave the way the caller expects, for example:

double d = { 1, 2, 3}
setReferencePoint(d);
d[0] = 3;

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or to make sure the documentation to setReferencePoint explains that it will hold a reference to the array and the user should not modify it.

Wiki MarkupIn fact we generally discourage the use of {{double\[3\]}} for momentum or space point. Try using Hep3Vector instead:

http://java.freehep.org/freehep-physics/apidocs/hep/physics/vec/Hep3Vector.html^{Image Removed}