2.JDBC-02

1 driverClass = com.mysql.jdbc.Driver
2 url = jdbc:mysql://localhost:3306/day02
3 user = root
4 password = 123456

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ResourceBundle;

public class JdbcUtils01 {
    static final String DRIVERCLASS;
    static final String URL;
    static final String USER;
    static final String PASSWORD;
    
    static{              //静态代码块
        //获取ResourceBundle    ctrl+2 松手按L
        //块编辑 alt+shift+a
        //变大写ctrl+shift+x
        //变小写ctrl+shift+y
        //向下复制一行alt+ctrl+下箭头
        //向上复制一行alt+ctrl+上箭头
        ResourceBundle bundle = ResourceBundle.getBundle("jdbc");
        
        //获取指定内容
        DRIVERCLASS = bundle.getString("driverClass");
        URL = bundle.getString("url");
        USER = bundle.getString("user");
        PASSWORD = bundle.getString("password");
    }
    
    static{
        //注册驱动
        try {
            Class.forName(DRIVERCLASS);
        } catch (ClassNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

    public static Connection getConnection() throws SQLException {
        return DriverManager.getConnection(URL, USER, PASSWORD);
    }

    /**
     * 释放资源
     * @param conn 链接
     * @param st 语句执行者
     * @param rs 结果集
     */
    public static void closeResource(Connection conn, Statement st, ResultSet rs) {
        closeResultSet(rs);
        closeStatement(st);
        closeConn(conn);
    }
    /**
     * 释放链接
     * @param conn 链接
     */
    public static void closeConn(Connection conn) {
        if (conn != null) {
            try {
                conn.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
            conn = null;
        }
    }
    /**
     * 释放语句执行者
     * @param st 语句执行者
     */
    public static void closeStatement(Statement st) {
        if (st != null) {
            try {
                st.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
            st = null;
        }    
    }
    /**
     * 释放结果集
     * @param rs 结果集
     */
    public static void closeResultSet(ResultSet rs) {
        if (rs != null) {
            try {
                rs.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
            rs = null;
        }
    }
    
}

 1 //更新操作
 2     //@Test
 3     public void f4(){
 4         Connection conn = null;
 5         ResultSet rs = null;
 6         PreparedStatement st = null;
 7         
 8         try {
 9             conn = JdbcUtils01.getConnection();
10             String sql = "update category set cname = ? where cid = ?";
11             st = conn.prepareStatement(sql);
12             st.setString(1, "手机");
13             st.setString(2, "c006");
14             
15             int i = st.executeUpdate();
16             
17             if(i==1){
18                 System.out.println("success");
19             }else{
20                 System.out.println("fail");
21             }
22             
23         } catch (SQLException e) {
24             e.printStackTrace();
25         }finally{
26             //释放资源
27             JdbcUtils01.closeResource(conn, st, rs);
28         }    
29     }
30     
31     //删除操作
32     @Test
33     public void f5(){
34         Connection conn = null;
35         ResultSet rs = null;
36         PreparedStatement st = null;
37         
38         try {
39             conn = JdbcUtils01.getConnection();
40             String sql = "delete from category where cid = ?";
41             st = conn.prepareStatement(sql);
42             st.setString(1, "c006");
43             
44             int i = st.executeUpdate();
45             if(i==1){
46                 System.out.println("success");
47             }else{
48                 System.out.println("fail");
49             }
50         } catch (SQLException e) {
51             e.printStackTrace();
52         }finally{
53             JdbcUtils01.closeResource(conn, st, rs);
54         }
55     }

1                //创建连接池
2 　　　　　　BasicDataSource ds = new BasicDataSource();
3 
4 　　　　　　//配置信息
5 　　　　　　ds.setDriverClassName("com.mysql.jdbc.Driver");
6 　　　　　　ds.setUrl("jdbc:mysql:///day07");
7 　　　　　　ds.setUsername("root");
8 　　　　　　ds.setPassword("1234");                        

1 //存放配置文件
2 Properties prop = new Properties();
3 prop.load(new FileInputStream("src/dbcp.properties"));
4 //设置
5 //prop.setProperty("driverClassName", "com.mysql.jdbc.Driver");
6 //创建连接池
7 DataSource ds = new BasicDataSourceFactory().createDataSource(prop);