从hive中获取数据

MySQL中获取数据

public RestMsg<Object> getZhen( HttpServletRequest request) {

		RestMsg<Object> rm = new RestMsg<Object>();
        List<String> list =  new ArrayList();
		Connection conn = null;
		Statement stmt = null;
		ResultSet rs = null;
		try {
			//第一步：加载MySQL的JDBC的驱动
			Class.forName("com.mysql.jdbc.Driver");
			//取得连接的 url,能访问MySQL数据库的用户名,密码；数据库名
			String url = "jdbc:mysql://10.1.35.13:3306/tsinghuadaxue?useUnicode=true&characterEncoding=utf-8";
			String user = "root";
			String password = "root";
			//第二步：创建与MySQL数据库的连接类的实例
			conn = DriverManager.getConnection(url, user, password);
			//第三步：用conn创建Statement对象类实例 stmt
			stmt = conn.createStatement();
			//第四步：执行查询，用ResultSet类的对象，返回查询的结果
			String sql = "select DISTINCT xzname from zoning WHERE xzname like '%街道' or xzname LIKE '%镇' or xzname LIKE '%乡'";
			rs = stmt.executeQuery(sql);
			while(rs.next()){
				System.out.println(rs.getString(1));      //取得数据库中的数据
				list.add(rs.getString("xzname"));
			}
		} catch (ClassNotFoundException e) {
			//加载JDBC错误,所要用的驱动没有找到
			System.out.println("驱动加载错误");
		}catch (SQLException ex) {
			//显示数据库连接错误或查询错误
			System.err.println("SQLException:"+ex.getMessage());
		}  finally {
			try{
				if(rs != null) {
					rs.close();
					rs = null;
				}
				if(stmt != null) {
					stmt.close();
					stmt = null;
				}
				if(conn != null) {
					conn.close();
					conn = null;
				}
			}catch(SQLException e) {
				System.err.println("SQLException:"+e.getMessage());
			}
		}

		rm = rm.successMsg();
		rm.setResult(list);

		return rm;


	}

hive中获取数据

@Override
    public Map<String, Object> getResultBySelcet(String selectSql, String... field) {
        Map<String,Object> result = new HashMap<>();
        Connection con = null;
        Statement stmt = null;
        ResultSet datSet = null;
        try{
            Class.forName(jdbcHiveDriver);
            con = DriverManager.getConnection(jdbcHiveUrl, hiveUser, hivePwd);
            stmt = con.createStatement();
            datSet = stmt.executeQuery(selectSql);

            if(datSet != null){
                while(datSet.next()){
                    for(String name : field) {
                        if (datSet.getString(name) != null) {
                            result.put(name,datSet.getString(name));
                        }
                    }
                    break;
                }
            }
        }catch (Exception e){
            e.printStackTrace();
        }finally {
            try {
                if (datSet != null) {
                    datSet.close();
                }
                if(stmt != null){
                    stmt.close();
                }
                if(con != null){
                    con.close();
                }
            }catch (Exception e){
                e.printStackTrace();
            }
        }
        return result;
    }

    @Override
    public List<Map<String, Object>> getAllResultBySelcet(String selectSql, String... field) {
        List<Map<String,Object>> result = new ArrayList<>();
        Connection con = null;
        Statement stmt = null;
        ResultSet rs = null;
        try {
            Class.forName(jdbcHiveDriver);
            con = DriverManager.getConnection(jdbcHiveUrl, hiveUser, hivePwd);
            stmt = con.createStatement();
            rs = stmt.executeQuery(selectSql);

            while (rs.next()) {
                Map<String,Object> temp = new HashMap<>();
                for(String name : field) {
                    if (rs.getString(name) != null) {
                        temp.put(name,rs.getString(name));
                    }
                }
                result.add(temp);
            }
            rs.close();
        }catch (Exception e){
            e.printStackTrace();
        }
        finally {
            try {
                if (rs != null) {
                    rs.close();
                }
                if(stmt != null){
                    stmt.close();
                }
                if(con != null){
                    con.close();
                }
            }catch (Exception e){
                e.printStackTrace();
            }
        }
        return result;
    }

最后

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