The length of an array in Java is immutable. So, you need to copy the desired part into a new array.
Use copyOfRange
method from java.util.Arrays class:
int[] newArray = Arrays.copyOfRange(oldArray, startIndex, endIndex);
startIndex is the initial index of the range to be copied, inclusive.
endIndex is the final index of the range to be copied, exclusive. (This index may lie outside the array)
E.g.:
//index 0 1 2 3 4
int[] arr = {10, 20, 30, 40, 50};
Arrays.copyOfRange(arr, 0, 2); // returns {10, 20}
Arrays.copyOfRange(arr, 1, 4); // returns {20, 30, 40}
Arrays.copyOfRange(arr, 2, arr.length); // returns {30, 40, 50} (length = 5)