标签：数据 文件 连接 final test pack rgs com blog
1,在根目录创建 mysql.properties 文件,使用这个文件是为了方便以后生成class文件后可修改链接任意数据库
2,导入jar包，自行百度下载。
3,写一个 SqlUtil.class （Sql工具类）
package com.sogood.util;
import java.io.IOException;
import java.sql.*;
import java.util.Properties;
public class SqlUtil {
private static String username;
private static String password;
private static String url;
static {
Properties pps = new Properties();
try {
pps.load(SqlUtil.class.getResourceAsStream("/com/sogood/mysql.properties"));
username = pps.getProperty("username");
password = pps.getProperty("password");
url = pps.getProperty("url");
} catch (IOException e) {
e.printStackTrace();
}
}
public static Connection getConnection() {
Connection con = null;
try {
Class.forName("com.mysql.jdbc.Driver");
con = DriverManager.getConnection(url, username, password);// 创建数据连接
} catch (SQLException e) {
e.printStackTrace();
System.out.println("数据库连接失败");
} catch (ClassNotFoundException e) {
throw new RuntimeException("驱动类找不到");
}
return con;
}
public static void close(Connection con, Statement stm, ResultSet rs) {
if (rs != null) {
try {
rs.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if (stm != null) {
try {
stm.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if (con != null) {
try {
con.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
}
4，写一个Demo.class 类测试一下
1 package com.sogood.jdbc; 2 3 import com.sogood.util.SqlUtil; 4 5 import java.sql.Connection; 6 import java.sql.ResultSet; 7 import java.sql.SQLException; 8 import java.sql.Statement; 9 10 public class Demo { 11 public static void main(String[] args) throws SQLException { 12 query(); 13 } 14 15 private static void query() { 16 Connection con = null; 17 Statement stm = null; 18 ResultSet rs = null; 19 try { 20 con = SqlUtil.getConnection(); 21 String sql = "SELECT * FROM STUDENT"; 22 stm = con.createStatement(); 23 rs = stm.executeQuery(sql); 24 System.out.println("查询结果:"); 25 while (rs.next()) { 26 int id = rs.getInt("id"); 27 System.out.println("id = " + id); 28 } 29 } catch (Exception e) { 30 e.printStackTrace(); 31 } finally { 32 SqlUtil.close(con, stm, rs); 33 } 34 } 35 }
jdbc，采用properties文件保存数据库账号密码以及链接
标签：数据 文件 连接 final test pack rgs com blog
原文地址：http://www.cnblogs.com/qiufuzong/p/6709692.html
