java-JDBC操作数据库

 1 package testJDBC;
 2 
 3 import java.sql.Connection;
 4 import java.sql.DriverManager;
 5 import java.sql.PreparedStatement;
 6 import java.sql.ResultSet;
 7 import java.sql.SQLException;
 8 import java.sql.Statement;
 9 
10 public class TestDB {
11     public static void main(String[] args) throws ClassNotFoundException, SQLException{
12         
13         String url = "jdbc:oracle:thin:@localhost:1521:orcl";
14         String username = "scott";
15         String password = "drew324";
16         
17         //first 
18         Class.forName("oracle.jdbc.driver.OracleDriver");
19         
20         //second
21         String sql = "select * from emp";
22         Connection connection = DriverManager.getConnection(url,username,password);
23         
24         //third
25         //Statement pstmt = connection.createStatement();
26         PreparedStatement pstmt = connection.prepareStatement(sql);
27         
28         //forth
29         //ResultSet resultSet = pstmt.executeQuery(sql);
30         ResultSet resultSet = pstmt.executeQuery();
31         
32         //fifth
33         while(resultSet.next()) {
34             System.out.println(resultSet.getInt(1));
35         }
36         
37         //sixth
38         resultSet.close();
39         pstmt.close();
40         connection.close();
41     }
42 
43 }