### Question:
CharTag { @Override public String toString() { int vLen = 0; if (value != null) vLen = value.length(); int sbSize = tagId.length() + lengthSize + vLen + 32; StringBuilder sb = new StringBuilder(sbSize) .append("tag: ") .append(tagId) .append(", len: ") .append(vLen); if (vLen > 0) sb.append(", value: ") .append(value); return sb.toString(); } protected  CharTag(String tagId, String value); String getTLV(); String getTagId(); String getValue(); @Override String toString();  }### Answer:
@Test void testToString() { assertEquals("tag: 02, len: 8, value: valueXYZ", instance.toString()); }
@Test void testToStringNullValue() { instance = tagMap.createTLV("K7", null); assertEquals("tag: K7, len: 0", instance.toString()); }