「javajdbc代码」jdbc的代码

博主:adminadmin 2023-03-20 09:31:09 282

本篇文章给大家谈谈javajdbc代码,以及jdbc的代码对应的知识点,希望对各位有所帮助,不要忘了收藏本站喔。

本文目录一览:

javajdbc代码解决

你每次执行增删改查的时候 都会注册一次JDBC驱动,目的只是简单的获取conn连接 ,建议单独编写一个获取conn的方法

pirvate Conntection getConn(){

return DriverManager.getConnection(url,username,password);

}

手打

在每次调用 通用方法的时候 获取一次这个方法即可

用java的动态代理模式写jdbc 求代码 谢谢

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.SQLException;

public class DBConnection {

private final String DRIVER="com.mysql.jdbc.Driver";//mysql数据库驱动

private final String URL="jdbc:mysql://localhost:3306/test";//url

private final String USERNAME="root";//用户名

private final String PASSWORD="root";

Connection conn=null;//定义对象

public DBConnection(){//初始化

try{

Class.forName(DRIVER);

conn =DriverManager.getConnection(URL,USERNAME,PASSWORD);//

System.out.println("连接成功!");

}

catch(ClassNotFoundException e){

e.printStackTrace();

}

catch(SQLException e){

e.printStackTrace();

}

}

public Connection getConnection(){

return this.conn;

}

public void distory(){//用完数据库关闭

try{

conn.close();

}

catch (SQLException e){

e.printStackTrace();

}

}

}

用的时候直接调用conn这个变量就可以了!!!!

java连接数据库的代码

用这个类吧.好的话,给我加加分.

import java.sql.*;

/**

* @功能: 一个JDBC的本地化API连接类,封装了数据操作方法,只用传一个SQL语句即可

* @作者: 李开欢

* @日期: 2007/

*/

public class ConnectionDemo {

/*

* 这里可以将常量全部放入另一个类中,以方便修改

*/

private static Connection conn;

private static Statement ps;

private static ResultSet rs;

private static final String DRIVER = "com.microsoft.jdbc.sqlserver.SQLServerDriver";

private static final String URL = "jdbc:microsoft:sqlserver://localhost:1433;DatabaseName=mydb";

private static final String USER ="sa";

private static final String PASS = "sa";

public ConnectionDemo() {

// TODO Auto-generated constructor stub

ConnectionDemo.getConnection();

}

public static Connection getConnection(){

System.out.println("连接中...");

try {

Class.forName(ConnectionDemo.DRIVER);

conn = DriverManager.getConnection(ConnectionDemo.URL, ConnectionDemo.USER, ConnectionDemo.PASS);

System.out.println("成功连接");

} catch (ClassNotFoundException e) {

// TODO Auto-generated catch block

e.printStackTrace();

} catch (SQLException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

return conn;

}

public static Statement getStatement(String sql){

System.out.println("执行SQL语句中...");

try {

ps = conn.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE, ResultSet.CONCUR_UPDATABLE);

if(sql.substring(0, 6).equals("select")){

rs = ps.executeQuery(sql);

System.out.println("执行完查询操作,结果已返回ResultSet集合");

}else if(sql.substring(0, 6).equals("delete")){

ps.executeUpdate(sql);

System.out.println("已执行完毕删除操作");

}else if(sql.substring(0, 6).equals("insert")){

ps.executeUpdate(sql);

System.out.println("已执行完毕增加操作");

}else{

ps.executeUpdate(sql);

System.out.println("已执行完毕更新操作");

}

} catch (SQLException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

return ps;

}

public static ResultSet getResultSet(){

System.out.println("查询结果为:");

return rs;

}

public static void closeConnection(){

System.out.println("关闭连接中...");

try {

if (rs != null) {

rs.close();

System.out.println("已关闭ResultSet");

}

if (ps != null) {

ps.close();

System.out.println("已关闭Statement");

}

if (conn != null) {

conn.close();

System.out.println("已关闭Connection");

}

} catch (Exception e) {

// TODO: handle exception

}

}

public static void main(String[] args) {

// TODO Auto-generated method stub

ConnectionDemo.getConnection();

String sql = "delete from type where id = 1";

ConnectionDemo.getStatement(sql);

String sql2 = "insert into type values(1,'教学设备')";

ConnectionDemo.getStatement(sql2);

String sql1 = "select * from type";

ConnectionDemo.getStatement(sql1);

ResultSet rs = ConnectionDemo.getResultSet();

System.out.println("编号 "+"类 型");

try {

while(rs.next()){

System.out.print(" "+rs.getInt(1)+" ");

System.out.println(rs.getString(2));

}

} catch (SQLException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

ConnectionDemo.closeConnection();

}

}

java 实现 jdbc连接oracle 数据库的java代码怎么写

package com.jdbc.test;

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.ResultSet;

import java.sql.Statement;

public class JDBCTest {

public static void main(String[] args) throws Exception {

//1.加载驱动

//Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");

//Class.forName("com.mysql.jdbc.Driver");

Class.forName("oracle.jdbc.driver.OracleDriver");

//2.创建数据库连接对象

//Connection conn = DriverManager.getConnection("jdbc:sqlserver://localhost:1433;databaseName=db","sa","sqlpass");

//Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/db?useUnicode=truecharacterEncoding=UTF-8","root","123456");

Connection conn = DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl","scott","Oracle123");

//3.创建数据库命令执行对象

Statement stmt = conn.createStatement();

// PreparedStatement ps = conn.prepareStatement("select * from t_user");

//4.执行数据库命令

ResultSet rs = stmt.executeQuery("select * from t_user");

// ResultSet rs = ps.executeQuery();

//5.处理执行结果

while (rs.next()) {

int id = rs.getInt("id");

String username = rs.getString("username");

String password = rs.getString("password");

System.out.println(id + "\t" + username + "\t" + password);

}

//6.释放数据库资源

if (rs != null) {

rs.close();

}

// if (ps != null) {

// ps.close();

// }

if (stmt != null) {

stmt.close();

}

if (conn != null) {

conn.close();

}

}

}

这是以前写的3中数据库的链接已经测试过了。

关于javajdbc代码和jdbc的代码的介绍到此就结束了,不知道你从中找到你需要的信息了吗 ?如果你还想了解更多这方面的信息,记得收藏关注本站。