array-utils-to-cast-array.md

Java cast primitive arrays and primitive wrapper arrays

Before talk about ArrayUtils library lets remember some concepts:

• You can't cast differents wrapper types because they are a Objects
• For number wrapper types you can always use base class 'Number' methods. For instance:

Double d = new Double(2.5);
int i = d.intValue();

• Equal wrapper and primitive types (as Double and double) can be casted implicitly

double dm = new Double(1);

• Is impossible cast differents wrapper and primitive types, also explicitly

//This line will crash
int im = (int) new Double(0);

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To cast primitive arrays and wrapper arrays use ArrayUtils library from apache

import org.apache.commons.lang.ArrayUtils;

ArrayUtils.toPrimitive(Boolean[] array);
ArrayUtils.toObject(boolean[] array)