What is the default initialization of an array in Java?

Question

So I\'m declaring and initializing an int array:

static final int UN = 0;
int[] arr = new int[size];
for (int i = 0; i < size; i++) {
    arr[i] = UN;
}
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Answer 1

From the Java Language Specification:

• Each class variable, instance variable, or array component is initialized with a default value when it is created (§15.9, §15.10):

  • For type byte, the default value is zero, that is, the value of (byte)0.
  • For type short, the default value is zero, that is, the value of (short)0.
  • For type int, the default value is zero, that is, 0.
  • For type long, the default value is zero, that is, 0L.
  • For type float, the default value is positive zero, that is, 0.0f.
  • For type double, the default value is positive zero, that is, 0.0d.
  • For type char, the default value is the null character, that is, '\u0000'.
  • For type boolean, the default value is false.
  • For all reference types (§4.3), the default value is null.