@Test
  public void testColumnPrefixFilter() throws IOException {
    String filterString = " ColumnPrefixFilter('qualifier' ) ";
    ColumnPrefixFilter columnPrefixFilter = doTestFilter(filterString, ColumnPrefixFilter.class);
    byte[] columnPrefix = columnPrefixFilter.getPrefix();
    assertEquals("qualifier", new String(columnPrefix, StandardCharsets.UTF_8));
  }
This class tests ParseFilter.java It tests the entire work flow from when a string is given by
the user and how it is parsed to construct the corresponding Filter object
hbase-server/src/test/java/org/apache/hadoop/hbase/filter/TestParseFilter.java