MyBatis学习笔记-Spring集成DAO层实现方式记录

Spring MyBatis 版本如下：

spring                  4.2.6.RELEASE

mybatis                3.4.0

mybatis-spring    1.3.0

Spring集成MyBatis的DAO层两种实现方式如下

第一种基于传统DAO层接口实现类方式：

public interface IUserDAO extends IGenericDAO {

}

@Repository("userDAO")
public class UserDAOImpl extends GenericDAOImpl implements IUserDAO {

}

@Repository("genericDAO")
public class GenericDAOImpl
	extends SqlSessionDaoSupport implements IGenericDAO {

	@Resource(name = "sqlSessionTemplate")
	protected SqlSessionTemplate sqlSessionTemplate = null;

	public static final String INSERT = "insert";
	public static final String INSERT_BATCH = "insertBatch";
    	public static final String UPDATE = "update";
    	public static final String UPDATE_BATCH = "updateBatch";
    	public static final String DELETE_BY_PK = "deleteByPK";
    	public static final String READ_DATA_BY_PK = "readDataByPK";
    	public static final String READ_DATA_BY_CONDITION = "readDataByCondition";
    	public static final String READ_DATA_LIST_BY_CONDITION = "readDataListByCondition";
    	public static final String READ_DATA_PAGINATION_BY_CONDITION = "readDataPaginationByCondition";
    	public static final String READ_COUNT_BY_CONDITION = "readCountByCondition";

	
	private Class entityClass = null;

	@SuppressWarnings("unchecked")
	public GenericDAOImpl() {
        Type type = getClass().getGenericSuperclass();
        if (type instanceof ParameterizedType) {
            entityClass = (Class) ((ParameterizedType) type).getActualTypeArguments()[0];
        }
	}
	
	@Override
	@Resource(name = "sqlSessionTemplate")
	public void setSqlSessionTemplate(SqlSessionTemplate sqlSessionTemplate) {
		super.setSqlSessionTemplate(sqlSessionTemplate);
	}
	
	protected SqlSession sqlSession() {
		return sqlSessionTemplate.getSqlSessionFactory().openSession();
	}
	
	protected void closeSession(SqlSession sqlSession) {
		if (null != sqlSession) sqlSession.close();
	}
	
	protected SqlSession batchSqlSession() {
		return sqlSessionTemplate.getSqlSessionFactory().openSession(ExecutorType.BATCH);
	}

	protected String obtainSQLID(String sqlId) {
		Configuration configuration = sqlSessionTemplate.getConfiguration();
		String dialect = "mysql";
		if (null != configuration.getVariables()) {
			dialect = configuration.getVariables().getProperty("dialect");
		}
		StringBuffer sb = new StringBuffer();
		sb.append(dialect).append(".").append(entityClass.getName()).append(".").append(sqlId);
		return sb.toString();
	}

	@Override
	public void insert(Entity entity) {
		sqlSessionTemplate.insert(obtainSQLID(INSERT), entity);
	}
	
	@Override
	public void insert(List entities) throws DataException {
		SqlSession sqlSession = batchSqlSession();
		for (int i = 0, len = entities.size(); i < len; i++) {
			sqlSession.insert(obtainSQLID(INSERT), entities.get(i));
		}
		sqlSession.flushStatements();
		closeSession(sqlSession);
	}

	@Override
	public void update(Entity entity) {
		sqlSessionTemplate.update(obtainSQLID(UPDATE), entity);
	}

	@Override
	public void update(List entities) throws DataException {
		SqlSession sqlSession = batchSqlSession();
		for (int i = 0, len = entities.size(); i < len; i++) {
			sqlSession.update(obtainSQLID(UPDATE), entities.get(i));
		}
		sqlSession.flushStatements();
		closeSession(sqlSession);
	}
	
	@Override
	public void delete(Entity entity) throws DataException {
		
	}

	@Override
	public void deleteByPK(PK primaryKey) {
		sqlSessionTemplate.delete(obtainSQLID(DELETE_BY_PK), primaryKey);
	}
	
	@SuppressWarnings("unchecked")
	@Override
	public Entity readDataByPK(PK pk) {
		return (Entity) sqlSessionTemplate.selectOne(obtainSQLID(READ_DATA_BY_PK), pk);
	}

	@SuppressWarnings("unchecked")
	@Override
	public Entity readDataByCondition(Query query) {
		Map map = query.getCondition();
		return (Entity) sqlSessionTemplate.selectOne(obtainSQLID(READ_DATA_BY_CONDITION), map);
	}
	
	@SuppressWarnings("unchecked")
	@Override
	public List readDataListByCondition(Query query) throws DataException {
		Map map = query.getCondition();
		List