code: public final boolean isLoaded() {
          checkMapped();
          if ((address == 0) || (capacity() == 0))
              return true;
          long offset = mappingOffset();
          long length = mappingLength(offset);
          return isLoaded0(mappingAddress(offset), length, Bits.pageCount(length));
      }
docs: Tells whether or not this buffer's content is resident in physical
  memory.
  
  <p> A return value of <tt>true</tt> implies that it is highly likely
  that all of the data in this buffer is resident in physical memory and
  may therefore be accessed without incurring any virtual-memory page
  faults or I/O operations.  A return value of <tt>false</tt> does not
  necessarily imply that the buffer's content is not resident in physical
  memory.
  
  <p> The returned value is a hint, rather than a guarantee, because the
  underlying operating system may have paged out some of the buffer's data
  by the time that an invocation of this method returns.  </p>
  
  @return <tt>true</tt> if it is likely that this buffer's content
  is resident in physical memory