Patch inclues following two methods and test cases for both.
1) New Method: ByteArrayOutputStream.toInputStream
ByteArrayOutputStream exposes its byte buffers by toByteArray(), which creates a fresh buffer and copy existing data to it.
A new method toInputStream() available in patch returns the current contents of baos, as an InputStream, avoiding unnecessary allocation and copying.
2) New Method: IOUtils.toFullyBufferedInputStream
There are situations where the InputStream source is available and it has to be passed to different modules for processing.
It is needed to fetch the full contents of the InputStream in internal buffer(IOUtils.toByteArray() ), convert this buffer to ByteArrayInputStream and use that stream instead. But this is wasteful since toByteArray() requires one fresh allocation and copy operation.
New method copies InputStream to ByteArrayOutputStream and returns baos.toInputStream(), avoiding unnecessary memory allocation and copy.
Testcases are available in respective classes.