eclipse如何连接mysqleclipse如何连接mysqleclipse如何连接mysqleclipse如何连接mysqleclipse如何连接mysqleclipse如何连接mysqleclipse如何连接mysql
建立一个hibernate的配置表
首先安装mysql数据库,具体安装方法可以上百度搜下,也可以按照下面的方法来安装mysql:
安装Mysql:
下载xampp,安装;
打开xampp 控制面板,启动mysql
把Mysql的执行文件路径添加到PATH环境变量中来
Mysql安装完成
下载mysql的连接jar包:mysql-connector-java-5.1.22-bin.jar;
启动......
答案就在这里:eclipse连接mysql
----------------------Hi,地球人,我是问答机器人小S,上面的内容就是我狂拽酷炫叼炸天的答案,除了赞同,你还有别的选择吗?
首先引入mysql-connector-java-5.1.37.jar这个jar包,然后下面代码就可以连接了:
Class.forName("com.mysql.jdbc.Driver");
Connection conn = (Connection) DriverManager.getConnection("jdbc:mysql://localhost:3306/db", "root", "");
Statement stmt = conn.createStatement();
ResultSet rs = stmt.executeQuery("select * from user");
下面这个方法就是连接MySQL数据库,当然你需要引入相应的包,import中所要引入的包即可,如3楼所说。
package com.icss.dao;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
/**
@author Ф
*
*/
public class BaseDao {
protected Connection conn;
protected void openconnection() throws ClassNotFoundException,SQLException{ //主要是这个方法,其他的不用看
try {
if( conn == null || conn.isClosed() ){
Class.forName("com.mysql.jdbc.Driver");
conn = DriverManager.getConnection("jdbc:mysql://127.0.0.1:3306/table","root","123456");//对应的是IP--用户名--密码
}
} catch (ClassNotFoundException e) {
throw e;
} catch (SQLException e) {
throw e;
}
}
public void closeResource(){
if(conn != null){
try {
conn.close();
conn = null;
} catch (Exception e) {
e.printStackTrace();
}
}
}
public void beginTransaction() throws Exception{
this.openconnection();
if(conn != null){
conn.setAutoCommit(false);
}
}
public void commit() throws Exception{
if(conn != null){
conn.commit();
}
}
public void rollback() throws Exception{
if(conn != null){
conn.rollback();
}
}
}
如何使用这个方法?
package com.icss.dao;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.ArrayList;
import java.util.List;
import com.icss.service.dto.OrderFlow;
public class FlowDao extends BaseDao{
public List<OrderFlow> getFlowInfo(String orderid) throws Exception{
List<OrderFlow> flows = null;
String sql="select o.state,o.orderinfo,o.uname,o.orderid,f.flowinfo " +
" from tflow f,torder o where o.orderid = f.orderid and o.orderid=?";//这里是sql语句,你随便
this.openconnection();
PreparedStatement ps = this.conn.prepareStatement(sql);
ps.setString(1, orderid);
ResultSet rs = ps.executeQuery();//这里是执行sql语句,并把结果返回给rs这个对象,其中resultset是sql包自带的类,不要担心
if(rs != null){//下面的代码是告诉你如何取出来刚才查到的数据
flows = new ArrayList<OrderFlow>();
while(rs.next()){
OrderFlow flow = new OrderFlow();
flow.setFlowinfo(rs.getString("flowinfo"));
flow.setOrderid(rs.getString("orderid"));
flow.setOrderinfo(rs.getString("orderinfo"));
flow.setUname(rs.getString("uname"));
flows.add(flow);
}
}
return flows;
}
}
注:如果你觉得封装成方法比较麻烦,你完全可以把上面主要的代码拿过来全部写到main函数中也行,相比而言前者可能更加面向对象,更加灵活,想必你也知道。ok,就这些。
String sql="select o.state,o.orderinfo,o.uname,o.orderid,f.flowinfo " +
" from tflow f,torder o where o.orderid = f.orderid and o.orderid=?";//这里是sql语句,你随便写
Class.forName("com.mysql.jdbc.Driver");
conn = DriverManager.getConnection("jdbc:mysql://127.0.0.1:3306/table","root","123456");//对应的是IP--用户名--密码
PreparedStatement ps = conn.prepareStatement(sql);
ResultSet rs = ps.executeQuery();//这里是执行sql语句,并把结果返回给rs这个对象,其中resultset是sql包自带的类,不要担心
if(rs != null){//下面的代码是告诉你如何取出来刚才查到的数据
flows = new ArrayList<OrderFlow>();
while(rs.next()){
OrderFlow flow = new OrderFlow();
flow.setFlowinfo(rs.getString("flowinfo"));
flow.setOrderid(rs.getString("orderid"));
flow.setOrderinfo(rs.getString("orderinfo"));
flow.setUname(rs.getString("uname"));
flows.add(flow);
}
}
首先引入mysql-connector-java-5.1.37.jar这个jar包,然后下面代码就可以连接了:
Class.forName("com.mysql.jdbc.Driver");
Connection conn = (Connection) DriverManager.getConnection("jdbc:mysql://localhost:3306/db", "root", "");
Statement stmt = conn.createStatement();
ResultSet rs = stmt.executeQuery("select * from user");
三楼 方式
JDBC啊,感觉这个问题很奇怪,应该是怎么使用java连接Mysql数据库吧,eclipse是的ide,不能连接mysql啊