public String readWPHexString(int numOfBytes) throws IOException {
        StringBuilder b = new StringBuilder();
        for (int i = 0; i < numOfBytes; i++) {
            b.append(readWPHex());
        }
        return b.toString();
    }
@Test
    public void testReadHexString() throws Exception {
        try (WPInputStream wpInputStream = emptyWPStream()) {
            wpInputStream.readWPHexString(10);
            fail("should have thrown EOF");
        } catch (EOFException e) {
            //swallow
        }
    }