Java Utililty Methods ByteBuffer Expand

ByteBuffer expand(ByteBuffer bb, int minSize, int maxSize)
Ensure that specified buffer has at least enough capacity to accommodate 'minSize' additional bytes, but not more than 'maxSize' additional bytes.

if (maxSize != -1 && maxSize < minSize) {
 throw new IllegalArgumentException("maxSize < minSize");
if (bb == null) {
 int size = Math.max(minSize, INITIAL_CAPACITY);
 if (maxSize != -1 && size > maxSize)
 size = maxSize;
 return ByteBuffer.allocate(size);
...

ByteBuffer expandBuffer(ByteBuffer existingBuffer, int additionalRequired)
expand Buffer

int pos = existingBuffer.position();
if ((pos + additionalRequired) > existingBuffer.limit()) {
 if ((pos + additionalRequired) < existingBuffer.capacity()) {
 existingBuffer.limit(pos + additionalRequired);
 } else {
 int newCapacity = existingBuffer.capacity() + additionalRequired;
 java.nio.ByteBuffer newBuffer = java.nio.ByteBuffer.allocate(newCapacity);
 existingBuffer.flip();
...