The java.io package functionally overlaps the java.nio package. There is duplication in both the Java and native code layers. Saliently, much of the functionality of the FileInputStream, FileOutputStream, and RandomAccessFile classes is duplicative of capabilities available in NIO's FileChannel. Layering java.io on top of java.nio would increase consistency across the two packages and allow for the removal of much of the java.io native code, if not an overall reduction in the overall number of lines of code in general.