### Question:
SingleCellExtractor implements ByteArrayExtractor { @Override public boolean isApplicable(KeyValue keyValue) { return CellUtil.matchingColumn(keyValue, columnFamily, columnQualifier); } SingleCellExtractor(byte[] columnFamily, byte[] columnQualifier); @Override Collection<byte[]> extract(Result result); @Override byte[] getColumnFamily(); @Override byte[] getColumnQualifier(); @Override boolean isApplicable(KeyValue keyValue); @Override boolean containsTarget(Result result);  }### Answer:
@Test public void testIsApplicable_Match() { assertTrue(extractor.isApplicable(new KeyValue(ROW, COLUMN_FAMILY, COLUMN_QUALIFIER, Bytes.toBytes("value")))); }
@Test public void testIsApplicable_NoMatch_WrongFamily() { assertFalse(extractor.isApplicable(new KeyValue(ROW, Bytes.toBytes("wrong family"), COLUMN_QUALIFIER, Bytes.toBytes("value")))); }
@Test public void testIsApplicable_NoMatch_WrongQualifier() { assertFalse(extractor.isApplicable(new KeyValue(ROW, COLUMN_FAMILY, Bytes.toBytes("wrong qualifier"), Bytes.toBytes("value")))); }