单元测试应用示例——测试工具类

工具类cn.com.pcgames.gamehall2.util.SqlHelper是游戏大厅DAO层辅助工具类.例如:SqlHelper?.buildInsert(List<FieldDesc?> fields, String tablename,String[] excludes);
根据数据库表元信息，表名生成sql插入语句,使用示例代码如cn.com.pcgames.gamehall2.repository.impl.GameDAOImpl

   public class GameDAOImpl extends AbstractRepository<Game> implements GameDAO {

        private  List<FieldDesc> tableFields;

        public void setTableFields(List<FieldDesc> tableFields) {
                this.tableFields = tableFields;
        }

        public void init() {
                this.tableFields = SqlHelper.listFields(simpleJdbcTemplate, "game");
        }

        public GameDAOImpl() {
                super(Game.class);
        }

        public long createGame(Game game) {
                long gameId = idGenerator.generate("game", "gameId");
                game.setGameId(gameId);
                //SqlHelper生成插入语句
                String sql = SqlHelper.buildInsert(tableFields, "game", null);
                Object[] params = SqlHelper.getParameters(game, tableFields, null);
                int result = simpleJdbcTemplate.update(sql, params);

                return result == 1 ? gameId : 0;
        }
        
       ......
     }

如何单元测试SqlHelper.buildInsert?
测试SqlHelper.buildInsert(List<FieldDesc?> fields, String tablename,String[] excludes);方法，需要准备fields,tablename,excludes这三个参数

• 准备fields

fields是数据库表的元信息,元信息依赖SimpleJdbcTemplate对象根据表名获取,我们让测试类SqlHelperTest继承之AbstractTransactionalJUnit4SpringContextTests
以获得applicationContext对象的引用，然后注入SimpleJdbcTemplate对象.

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = { "classpath:applicationContext.xml" })
public class SqlHelperTest extends
                AbstractTransactionalJUnit4SpringContextTests {

        @Autowired
        SimpleJdbcTemplate simpleJdbcTemplate;

        ......
}

• 准备tablename,我们可以在数据库中创建一张表，用来测试

        private void createTesttable(String table) {

                simpleJdbcTemplate.update("DROP TABLE IF EXISTS `" + table + "`");

                simpleJdbcTemplate
                                .update("CREATE TABLE `" + table + "` ("
                                                + "`id` bigint(20) NOT NULL,"
                                                + "`createAt` timestamp NULL DEFAULT NULL,"
                                                + "`name` varchar(50) DEFAULT NULL,"
                                                + "`age` int(11) DEFAULT NULL,"
                                                + "`info` text,"
                                                + "`rate` float DEFAULT NULL,"
                                                + "PRIMARY KEY (`id`)"
                                                + ") ENGINE=InnoDB DEFAULT CHARSET=gbk;");

                Calendar calendar = Calendar.getInstance();
                calendar.set(Calendar.YEAR, 2011);
                calendar.set(Calendar.MONTH, 10);
                calendar.set(Calendar.DAY_OF_MONTH, 10);
                calendar.set(Calendar.HOUR_OF_DAY, 23);
                calendar.set(Calendar.MINUTE, 23);
                calendar.set(Calendar.SECOND, 23);

                int rows = simpleJdbcTemplate.update(
                                "INSERT INTO test_table VALUES(?,?,?,?,?,?)", new Object[] {
                                                393648562, calendar.getTime(), "chenyang", 25,
                                                "速度第一,完美第二",0.35 });

                Assert.assertEquals(1, rows);

        }

• excludes用来指定，哪些字段不参与构建sql插入语句，这里可以设置null
  

测试准备工作，做好了，下面就可以编写测试了

        @Test
        public void testBuildInsert() {
                List<FieldDesc> list = newFieldDescs();
                String insert = SqlHelper.buildInsert(list, "game", null);
                Assert.assertEquals("INSERT INTO game (gameId,createAt) VALUES (?,?)",
                                insert);

        }

        private List<FieldDesc> newFieldDescs() {
                List<FieldDesc> list = new ArrayList<FieldDesc>();
                FieldDesc id = new FieldDesc();
                id.setField("gameId");
                id.setType("int(11)");
                FieldDesc createAt = new FieldDesc();
                createAt.setField("createAt");
                createAt.setType("timestamp");
                list.add(id);
                list.add(createAt);
                return list;
        }