public static byte[] toByteArray(InputStream input) throws IOException {
    ByteArrayOutputStream output = new ByteArrayOutputStream();
    int n;
    byte[] buffer = new byte[4096];
    while (-1 != (n = input.read(buffer))) {
      output.write(buffer, 0, n);
    }

    return output.toByteArray();
  }
Even thought this is only used in a test, caller of MemberMXBean.processCommand(String, Map,
Byte[][]) will need to use this method to convert a fileList to Byte[][] to call that
deprecated API.

Once that deprecated API is removed, we can delete this method and the tests.
geode-core/src/main/java/org/apache/geode/management/internal/util/ManagementUtils.java