Java Utililty Methods Array Sub Array

String[] sub(String[] a, String[] b)
subtract b from a

TreeSet<String> s = new TreeSet<>(Arrays.asList(a));
s.removeAll(Arrays.asList(b));
if (s.size() != a.length) {
 return s.toArray(new String[s.size()]);
} else {
 return a;

List sub(T[] source, int first, int last)
sub

if (first < 0 || last < 0 || first >= source.length || last >= source.length)
 throw new ArrayIndexOutOfBoundsException();
List<T> result = new ArrayList<T>();
for (int i = first; i <= last; i++)
 result.add(source[i]);
return result;

boolean[] subarray(boolean[] array, int fromIndex, int length)
Building on the arraycopy function in System, this function returns a "subarray" of a larger array.

boolean[] tempArray = new boolean[length];
try {
 System.arraycopy(array, fromIndex, tempArray, 0, tempArray.length);
} catch (ArrayIndexOutOfBoundsException e) {
 System.out.println("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
 System.out.println("Array of length:" + array.length);
 System.out.println("From index with length:" + fromIndex + "," + length);
 System.out.println("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
...

byte[] subArray(byte[] a, int beginIndex, int endIndex)
Returns the new array that is the sub-array of the specified array .

if (a == null || a.length == 0 || beginIndex < 0 || endIndex > a.length || beginIndex > endIndex) {
 return new byte[0];
} else {
 byte[] b = new byte[endIndex - beginIndex];
 System.arraycopy(a, beginIndex, b, 0, b.length);
 return b;

byte[] subArray(byte[] array, int beginIndex, int endIndex)
Extract a sub array of bytes out of the byte array.

int length = endIndex - beginIndex;
byte[] subarray = new byte[length];
System.arraycopy(array, beginIndex, subarray, 0, length);
return subarray;

byte[] subarray(byte[] array, int offset, int length)
NOTE: subarray method implemented for arrays of type byte Extracts a sub array from an array of a primitive type.

validateOffsetLength(array, array.length, offset, length);
byte[] sub = new byte[length];
for (int i = 0; i < length; i++)
 sub[i] = array[offset + i];
return sub;

byte[] subarray(byte[] array, int startIndexInclusive, int endIndexExclusive)

Produces a new byte array containing the elements between the start and end indices.

The start index is inclusive, the end index exclusive.

if (array == null) {
 return null;
if (startIndexInclusive < 0) {
 startIndexInclusive = 0;
if (endIndexExclusive > array.length) {
 endIndexExclusive = array.length;
...

byte[] subarray(byte[] array, int startIndexInclusive, int endIndexExclusive)
subarray

if (array == null) {
 return null;
if (startIndexInclusive < 0) {
 startIndexInclusive = 0;
if (endIndexExclusive > array.length) {
 endIndexExclusive = array.length;
...

byte[] subArray(byte[] b, int offset, int length)
Return a subarray of the byte array in parameter.

byte[] sub = new byte[length];
for (int i = offset; i < offset + length; i++)
 sub[i - offset] = b[i];
return sub;

byte[] subarray(byte[] b, int ofs, int len)
subarray

byte[] out = new byte[len];
System.arraycopy(b, ofs, out, 0, len);
return out;