### Question:
UTF7Base64Helper { public byte getChar (final int sextet) { return (byte) m_aAlphabet[sextet]; } UTF7Base64Helper(@Nonnull @Nonempty final String sAlphabet); int getSextet(final int ch); boolean contains(final char ch); byte getChar(final int sextet);  }### Answer:
@Test public void testGetChar () { assertEquals ('A', tested.getChar (0)); assertEquals ('/', tested.getChar (63)); assertEquals ('a', tested.getChar (26)); assertEquals ('0', tested.getChar (52)); }