class UnsafeByteArrayInputStream extends InputStream {

    @Override
    public void mark(int readAheadLimit) {
        mMark = mPosition;
    }

    public  UnsafeByteArrayInputStream(byte[] buf);
    public  UnsafeByteArrayInputStream(byte[] buf, int offset);
    public  UnsafeByteArrayInputStream(byte[] buf, int offset, int length);

}