declare array with values java

1int intArray[];    //declaring array
2intArray = new int[20];  // allocating memory to array
3//OR
4int[] intArray = new int[20]; // combining both statements in one

1int[] array = new int[/*size*/];
2// Works for double, char, etc.

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

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

1int[] arr = new int[n];