Spring 学习笔记（四）—— bean配置之数据库连接

本人使用的是SQL Server数据库，一个名为demo的数据库下有note和userT两个表，如下图：

 

两个表的内容如下图：

接下来在Bean.xml配置数据库的连接：

以上配置用到了3个jar包，如有需要，可到https://download.csdn.net/download/m940034240/10849605下载

接下来在代码中进行简单的查询

public class SQLServerQueryApp {		
   public static void main(String[] args) {
      ApplicationContext context = 
             new ClassPathXmlApplicationContext("Beans.xml");
      //使用jdbc
      JdbcTemplate jdbcTemplateObject = new JdbcTemplate((DataSource) context.getBean("dataSource")) ;
      String SQL = "select count(*) from dbo.[userT]";
      int rowCount = jdbcTemplateObject.queryForObject(SQL, Integer.class);
      System.out.println("userT表数据条数："+rowCount);   
      
      //使用c3p0
      DataSource ds = context.getBean("dataSource2", DataSource.class);
      Connection conn;
		try {
			conn = ds.getConnection();
			 PreparedStatement pStatement = conn.prepareStatement("select * from note");
		      ResultSet resultSet =pStatement.executeQuery();
		      List> list = new ArrayList<>();
				while (resultSet.next()) {
					Map map = new HashMap<>();
					ResultSetMetaData metaData = resultSet.getMetaData();
					int count = metaData.getColumnCount();
					for(int i = 1; i <= count; i++) {
						Object object = resultSet.getObject(i);
						map.put(metaData.getColumnLabel(i), object);
					}
					list.add(map);
				}
				System.out.println("查询结果："+list.toString());
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
   }
}

运行输出结果：

userT表数据条数：24
查询结果：[{addTime=2018-04-18 09:59:55.0, name=1B281739B5BDC2D8118D27964688CB78_qq, editTime=null, title=2018-04-18的笔记, message=, audioPath=/storage/emulated/0/VoiceNote/1B281739B5BDC2D8118D27964688CB78_qq/2018_04_18_09_59_30/1524016795230.wav}, ........内容省略]