do java arrays need a length at initialization code example

Example 1: java create array with values

//Given values must match array type
int[] myIntArray = {1, 2, 3};

Example 2: declare array with values java

int[] myIntArray = new int[3];
int[] myIntArray = {1, 2, 3};
int[] myIntArray = new int[]{1, 2, 3};