/** * 查询语句的操作 * * @param sql 查询语句 * @param objects 查询语句的参数 * @return 结果集 */ public ResultSet select(String sql, Object... objects) { try { conn = DBManager.getConnection(); pstm = conn.prepareStatement(sql); if (objects != null && objects.length > 0) { for (int i = 0; i < objects.length; i++) { pstm.setObject(i + 1, objects[i]); } } rs = pstm.executeQuery(); } catch (SQLException e) { e.printStackTrace(); } return rs; }
/** * 根据条件查找信息 * * @param sql * @param t * @return */ public List findListTByCondition(String sql, T t) { List<T> list = new ArrayList<T>(); T vo = null; StringBuffer bsql = new StringBuffer(sql); bsql.append(" 1=1 "); Class tclazz = t.getClass(); Field[] fields = t.getClass().getDeclaredFields(); // 获得属性 try { for (Field field : fields) { conn = DBManager.getConnection(); PropertyDescriptor pd = new PropertyDescriptor(field.getName(), tclazz); // 通过反射获取get方法的属性 Method getMethod = pd.getReadMethod(); // 执行get方法返回一个Object Object o = getMethod.invoke(t); // 执行get方法返回一个Object if (o != null) { // 生成根据信息查询的sql语句 bsql.append(" and ").append(field.getName()); bsql.append("='").append(o).append("'"); } } System.out.println(bsql); pstm = conn.prepareStatement(bsql.toString()); rs = pstm.executeQuery(); // 根据结果集返回集合 while (rs.next()) { vo = autoBeanByRs(rs); list.add(vo); } } catch (SQLException ex) { Logger.getLogger(BasicDao.class.getName()).log(Level.SEVERE, null, ex); } catch (IllegalAccessException ex) { Logger.getLogger(BasicDao.class.getName()).log(Level.SEVERE, null, ex); } catch (IllegalArgumentException ex) { Logger.getLogger(BasicDao.class.getName()).log(Level.SEVERE, null, ex); } catch (InvocationTargetException ex) { Logger.getLogger(BasicDao.class.getName()).log(Level.SEVERE, null, ex); } catch (IntrospectionException ex) { Logger.getLogger(BasicDao.class.getName()).log(Level.SEVERE, null, ex); } DBManager.close(conn, pstm, rs); return list; }
/** * 非查询语句的操作 * * @param sql 非查询的sql语句 * @param objects 非查询语句的参数 * @return 受影响的行数 */ public int executeUpdatePerparement(String sql, Object... objects) { int row = 0; try { conn = DBManager.getConnection(); // 创建prepareStatement ,预编译sql语句 pstm = conn.prepareStatement(sql); if (objects != null && objects.length > 0) { for (int i = 0; i < objects.length; i++) { // 使用给定对象设置指定参数的值。 pstm.setObject(i + 1, objects[i]); } } // 执行语句 row = pstm.executeUpdate(); DBManager.close(conn, pstm, rs); } catch (SQLException e) { e.printStackTrace(); } return row; }
/** * 返回一个实体类 * * @param sql 查询的sql语句 * @param t 传入的实体类 * @param objects 查询语句的参数 * @return 实体类 */ public T findByPredStatmentT(String sql, Object... objects) { T vo = null; try { conn = DBManager.getConnection(); pstm = conn.prepareStatement(sql); if (objects != null && objects.length > 0) { for (int i = 0; i < objects.length; i++) { pstm.setObject(i + 1, objects[i]); } } rs = pstm.executeQuery(); while (rs.next()) { vo = autoBeanByRs(rs); } } catch (SQLException e) { e.printStackTrace(); } DBManager.close(conn, pstm, rs); return vo; }
/** * 根据sql语句查找数据库中的记录 * * @param sql 要查找的Sql语句 * @param objects 传入的参数 * @return 返回的List集合 */ public List<T> findListT(String sql, Object... objects) { List<T> list = new ArrayList<T>(); T vo = null; try { conn = DBManager.getConnection(); pstm = conn.prepareStatement(sql); if (objects != null && objects.length > 0) { for (int i = 0; i < objects.length; i++) { pstm.setObject(i + 1, objects[i]); } } rs = pstm.executeQuery(); while (rs.next()) { vo = autoBeanByRs(rs); list.add(vo); } } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } DBManager.close(conn, pstm, rs); return list; }