• JDBC的实例


    实例1.  使用纯Java的方式连接数据库

     3   import java.sql.Connection;
     4   import java.sql.DriverManager;
     5   import java.sql.SQLException;
     6   
     7   
     8   public class Test1 {
     9   
    10       public static void main(String[] args){
    11          //1:加载数据库驱动
    12           try {
    13              Class.forName("com.mysql.jdbc.Driver");
    14          } catch (ClassNotFoundException e) {
    15              e.printStackTrace();
    16         }
    17          
    18          
    19        
    20         //2:建立连接,获得Connection对象
    21 
    22         //Eclipse:导入包的快捷键:Ctrl+Shift+O
    23          //代码的格式化:Ctro+Shift+F
    24           
    25           Connection conn=null;
    26          try {
    27             conn=DriverManager.getConnection("jdbc:mysql://localhost:3306/day01","root","root");
    28              System.out.println("連接成功");
    29          } catch (SQLException e) {
    30              e.printStackTrace();
    31          }
    32              //3.获取Statement对象
    33         try {
    34             stmt=conn.createStatement();
    35             //stmt.execute(sql);
    36             stmt.executeUpdate(sql);
    37             
    38         } catch (Exception e) {
    39         }
    40          
    41         //4:关闭资源
    42           try {
    43            conn.close();
    44        } catch (SQLException e) {
    45              e.printStackTrace();
    46         }
    47      }
    48     }

    需求:使用ResultSet查询dog信息

     1 import java.sql.Connection;
     2 import java.sql.DriverManager;
     3 import java.sql.ResultSet;
     4 import java.sql.Statement;
     5 
     6 /**
     7  * 需求:使用ResultSet查询dog信息
     8  * 
     9  * @author10  *
    11  */
    12 
    13 public class Test3 {
    14     public static void main(String[] args) {
    15         Connection conn = null;
    16         Statement stmt = null;
    17         ResultSet rs = null;
    18 
    19         String url = "jdbc:mysql://localhost:3306/day01";
    20         String user = "root";
    21         String password = "root";
    22         String sql = "SELECT * FROM dog";
    23 
    24         try {
    25             Class.forName("com.mysql.jdbc.Driver");
    26             conn = DriverManager.getConnection(url, user, password);
    27             stmt = conn.createStatement();
    28             rs = stmt.executeQuery(sql);
    29 
    30             // 遍历rs
    31             // rs.next();指针下移    
    32             while (rs.next()) {
    33                 // 在MySql数据库中index从1开始
    34                 System.out.println(rs.getObject(1) + "	");
    35                 System.out.println(rs.getObject(2) + "	");
    36                 System.out.println(rs.getObject("health") + "	");
    37                 System.out.println(rs.getObject("love") + "	");
    38                 System.out.println(rs.getObject("strain") + "	");
    39 
    40             }
    41 
    42         } catch (Exception e) {
    43 
    44         } finally {
    45             try {
    46                 if (null != rs) {
    47                     rs.close();
    48                 }
    49                 if (null != stmt) {
    50                     stmt.close();
    51                 }
    52                 if (null != conn) {
    53                     conn.close();
    54                 }
    55             } catch (Exception e2) {
    56             }
    57 
    58         }
    59 
    60     }
    61 }
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  • 原文地址:https://www.cnblogs.com/binzhihua-666/p/6180744.html
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