### Question:
GenQuerySelectField extends GenQueryField { public static GenQuerySelectField instance(final RodsGenQueryEnum selectField, final SelectFieldTypes selectFieldType, final SelectFieldSource selectFieldSource) throws JargonException { if (selectField == null) { throw new JargonException("select field was null"); } return new GenQuerySelectField(selectField.getName(), String.valueOf(selectField.getNumericValue()), selectFieldType, selectFieldSource); } private  GenQuerySelectField(final String selectFieldColumnName, final String selectFieldNumericTranslation,
			final SelectFieldTypes selectFieldType, final SelectFieldSource selectFieldSource); static GenQuerySelectField instance(final RodsGenQueryEnum selectField,
			final SelectFieldTypes selectFieldType, final SelectFieldSource selectFieldSource); static GenQuerySelectField instance(final String selectFieldName, final String selectFieldNumericTranslation,
			final SelectFieldTypes selectFieldType, final SelectFieldSource selectFieldSource); @Override String toString(); SelectFieldTypes getSelectFieldType();  }### Answer:
@Test public final void testInstanceRodsGenQueryEnumSelectFieldTypesSelectFieldSource() throws Exception { GenQuerySelectField selectField = GenQuerySelectField.instance(RodsGenQueryEnum.COL_AUDIT_ACTION_ID, GenQuerySelectField.SelectFieldTypes.FIELD, GenQuerySelectField.SelectFieldSource.DEFINED_QUERY_FIELD); Assert.assertNotNull("null instance", selectField); }
@Test(expected = IllegalArgumentException.class) public final void testInstanceNullRodsGenQueryEnum() throws Exception { GenQuerySelectField.instance(null, GenQuerySelectField.SelectFieldTypes.FIELD, GenQuerySelectField.SelectFieldSource.DEFINED_QUERY_FIELD); }
@Test(expected = IllegalArgumentException.class) public final void testInstanceNullSelectFieldType() throws Exception { GenQuerySelectField.instance(RodsGenQueryEnum.COL_AUDIT_ACTION_ID, null, GenQuerySelectField.SelectFieldSource.DEFINED_QUERY_FIELD); }
@Test(expected = IllegalArgumentException.class) public final void testInstanceNullSelectFieldSource() throws Exception { GenQuerySelectField.instance(RodsGenQueryEnum.COL_AUDIT_ACTION_ID, GenQuerySelectField.SelectFieldTypes.FIELD, null); }
@Test public final void testInstanceWithNameAndType() throws Exception { GenQuerySelectField selectField = GenQuerySelectField.instance("blah", "1234", GenQuerySelectField.SelectFieldTypes.FIELD, GenQuerySelectField.SelectFieldSource.DEFINED_QUERY_FIELD); Assert.assertNotNull("null instance", selectField); }