1 導(dǎo)包
mysql 提供的實(shí)現(xiàn)java接口的包路徑
C:\Program Files (x86)\MySQL\Connector.J 5.1\mysql-connector-java-5.1.42-bin.jar
Eclipse 導(dǎo)包 兩種方式
1:Project - Properties - Java Build Path - Add External JARs - 選擇mysql包 // 指定包路徑
2:項(xiàng)目下建文件夾,復(fù)制包進(jìn)去,鼠標(biāo)右鍵 - Build Path - Add To Build Path // 拷貝包
2 JDBC的步驟 (5步)
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class Test {
public static void main(String[] args) {
try {
//1、驅(qū)動(dòng)類加載
Class.forName("com.mysql.jdbc.Driver");
//2、獲取數(shù)據(jù)庫(kù)連接
Connection conn = DriverManager.getConnection(
"jdbc:mysql://localhost:3306/db01","root","123456");
System.out.println(conn); //查看是否建立連接
//3 、通過連接,創(chuàng)建一個(gè)語句對(duì)象,這個(gè)對(duì)象用于執(zhí)行sql語句
Statement stmt = conn.createStatement();
// String sql = "insert into employee value(6,1003,'武松',25,'男','景陽岡',200,2)"; //添加員工
// String sql = "delete from employee where num = 6 "; //刪除員工
String sql = "select * from employee"; //查詢員工
//4、執(zhí)行sql語句
//Statement 的三種常用方式
// int count = stmt.executeUpdate(sql); //返回影響的行數(shù) 并執(zhí)行sql更新語句
// System.out.println(count);
// boolean flag = stmt.execute(sql); //返回值為ResultSet(查詢結(jié)果)才為true
// System.out.println(flag);
ResultSet rs = stmt.executeQuery(sql); //返回查詢結(jié)果
//使用迭代的方式遍歷
while(rs.next()){
System.out.println("姓名:" + rs.getString("name")
+ "\t年齡:" + rs.getInt(4) + "\t地址:" + rs.getString(6));
}
//5、關(guān)閉連接
stmt.close();
conn.close();
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
3 封裝JDBC工具包,以及使用外部配置文件
package com.yuxhu.jdbc.util;
import java.io.IOException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.util.Properties;
public class DBUtils {
static String driver;
static String url;
static String user;
static String password;
//靜態(tài)加載
static{
try {
//加載外部屬性文件
Properties ppt = new Properties();
//加載文件,加載的是類加器目錄下面的db.properties
ppt.load(DBUtils.class.getClassLoader().getResourceAsStream("db.properties"));
driver = ppt.getProperty("jdbc.driver");
url = ppt.getProperty("jdbc.url");
user = ppt.getProperty("jdbc.user");
password = ppt.getProperty("jdbc.password");
//1、驅(qū)動(dòng)類加載
Class.forName(driver);
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
//獲取連接
public static Connection getConnection(){
Connection conn = null;
try {
conn = DriverManager.getConnection(url,user,password);
} catch (SQLException e) {
e.printStackTrace();
}
return conn;
}
//關(guān)閉連接
public static void closeConnection(Connection conn){
if(conn != null){
try {
conn.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
}
#這是一個(gè)數(shù)據(jù)庫(kù)配置文件
#數(shù)據(jù)庫(kù)驅(qū)動(dòng)
jdbc.driver=com.mysql.jdbc.Driver
#數(shù)據(jù)庫(kù)數(shù)據(jù)源
jdbc.url=jdbc:mysql://192.168.0.202:3306/mydb
#數(shù)據(jù)庫(kù)用戶名
jdbc.user=root
#數(shù)據(jù)庫(kù)密碼
jdbc.password=123456
package com.yuxhu.jdbc.util;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class UtilTest {
public static void main(String[] args) {
try {
//使用定義的工具類DBUtils獲取連接
Connection conn = DBUtils.getConnection();
Statement stmt = conn.createStatement();
String sql = "select * from employee"; // 查詢員工
// 4、執(zhí)行sql語句
ResultSet rs = stmt.executeQuery(sql); // 返回查詢結(jié)果
// 使用迭代的方式遍歷
while (rs.next()) {
System.out.println("姓名:" + rs.getString("name") + "\t年齡:" + rs.getInt(4)
+ "\t地址:" + rs.getString(6));
}
// 5、關(guān)閉連接
stmt.close();
conn.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}