### Question:
Between extends BaseComparison { @Override public void appendValue(DatabaseType databaseType, StringBuilder sb, List<ArgumentHolder> argList) throws SQLException { if (low == null) { throw new IllegalArgumentException("BETWEEN low value for '" + columnName + "' is null"); } if (high == null) { throw new IllegalArgumentException("BETWEEN high value for '" + columnName + "' is null"); } appendArgOrValue(databaseType, fieldType, sb, argList, low); sb.append("AND "); appendArgOrValue(databaseType, fieldType, sb, argList, high); } Between(String columnName, FieldType fieldType, Object low, Object high); @Override void appendOperation(StringBuilder sb); @Override void appendValue(DatabaseType databaseType, StringBuilder sb, List<ArgumentHolder> argList);  }### Answer:
@Test(expected = IllegalArgumentException.class) public void testAppendValueLowNull() throws Exception { new Between(COLUMN_NAME, numberFieldType, null, 20L).appendValue(null, new StringBuilder(), new ArrayList<ArgumentHolder>()); }
@Test(expected = IllegalArgumentException.class) public void testAppendValueHighNull() throws Exception { new Between(COLUMN_NAME, numberFieldType, 10L, null).appendValue(null, new StringBuilder(), new ArrayList<ArgumentHolder>()); }