java eclipse maven的安装和配置

目录

一、maven简介二、安装和配置maven1、安装maven2、配置maven环境变量

三、eclipse中配置maven1、点击window->perferences2、点击add3、点击Directory4、找到安装maven的根目录即可

四、案例1、entity实体类2、dao方法3、action层4、util包①DBHelper②config.peoperties

一、maven简介

Apache Maven是个项目管理和自动构建工具，基于项目对象模型（POM）的概念。 作用：完成项目的相关操作，如：编译，构建，单元测试，安装，网站生成和基于Maven部署项目。 xxx.class 百度—》 xxx.jar 在百度上进行下载 将xxx.jar导入工程中 私服 工程中的某一个xml文件中写入一个字符串，达到jar下载的作用

二、安装和配置maven

1、安装maven

网址：http://maven.apache.org/download.cgi

2、配置maven环境变量

①MAVEN_HOME 值放maven的安装路径 ②修改path：在其中加入%MAVEN_HOME%\bin ③验证

doc窗口执行命令“mvn –version”

三、eclipse中配置maven

1、点击window->perferences

2、点击add

3、点击Directory

4、找到安装maven的根目录即可

四、案例

1、entity实体类

package com.zking.entity;

public class User {

private Long id;

private String name;

private String loginName;

private String pwd;

private Long rid;

public Long getId() {

return id;

}

public void setId(Long id) {

this.id = id;

}

public String getName() {

return name;

}

public void setName(String name) {

this.name = name;

}

public String getLoginName() {

return loginName;

}

public void setLoginName(String loginName) {

this.loginName = loginName;

}

public String getPwd() {

return pwd;

}

public void setPwd(String pwd) {

this.pwd = pwd;

}

public Long getRid() {

return rid;

}

public void setRid(Long rid) {

this.rid = rid;

}

public User() {

super();

// TODO Auto-generated constructor stub

}

@Override

public String toString() {

return "User [id=" + id + ", name=" + name + ", loginName=" + loginName + ", pwd=" + pwd + ", rid=" + rid + "]";

}

}

2、dao方法

package com.zking.dao;

import java.sql.Connection;

import java.sql.PreparedStatement;

import java.sql.ResultSet;

import com.zking.entity.User;

import com.zking.util.DBAccess;

import com.zking.util.DBHelper;

public class UserDao {

// 登录

public User login(User u){

Connection con=null;

PreparedStatement ps=null;

ResultSet rs=null;

try {

con=DBAccess.getConnection();

String sql="select * from t_oa_user where loginName=? and pwd=?";

ps = con.prepareStatement(sql);

ps.setString(1, u.getLoginName());

ps.setString(2, u.getPwd());

rs=ps.executeQuery();

if(rs.next()) {

u.setId(rs.getLong(1));

u.setName(rs.getString(2));

u.setLoginName(rs.getString(3));

u.setPwd(rs.getString(4));

u.setRid(rs.getLong(5));

}

} catch (Exception e) {

e.printStackTrace();

}finally {

DBHelper.close(con, ps, rs);

}

return u;

}

}

3、action层

package com.zking.web;

import java.io.IOException;

import java.io.PrintWriter;

import javax.servlet.ServletException;

import javax.servlet.annotation.WebServlet;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.zking.dao.UserDao;

import com.zking.entity.User;

@WebServlet("/login.do")

public class UserAction extends HttpServlet{

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

doPost(req, resp);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

//设置编码方式

req.setCharacterEncoding("utf-8");

resp.setCharacterEncoding("utf-8");

resp.setContentType("text/html; charset=UTF-8");

//拿out

PrintWriter out = resp.getWriter();

UserDao ud=new UserDao();

//接收表单传值

String sname = req.getParameter("name");

String pwd = req.getParameter("pwd");

User u=new User();

u.setLoginName(sname);

u.setPwd(pwd);

User u1 = ud.login(u);

if(u1!=null) {

out.print("");

}else{

out.print("");

}

}

}

4、util包

①DBHelper

package com.zking.util;

import java.io.InputStream;

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.PreparedStatement;

import java.sql.ResultSet;

import java.sql.SQLException;

import java.sql.Statement;

import java.util.Properties;

/**

* 提供了一组获得或关闭数据库对象的方法

*

*/

public class DBHelper {

private static String driver;

private static String url;

private static String user;

private static String password;

static {// 静态块执行一次，加载 驱动一次

try {

InputStream is = DBHelper.class

.getResourceAsStream("config.properties");

Properties properties = new Properties();

properties.load(is);

driver = properties.getProperty("driver");

url = properties.getProperty("url");

user = properties.getProperty("user");

password = properties.getProperty("pwd");

Class.forName(driver);

} catch (Exception e) {

e.printStackTrace();

throw new RuntimeException(e);

}

}

/**

* 获得数据连接对象

*

* @return

*/

public static Connection getConnection() {

try {

Connection conn = DriverManager.getConnection(url, user, password);

return conn;

} catch (SQLException e) {

e.printStackTrace();

throw new RuntimeException(e);

}

}

public static void close(ResultSet rs) {

if (null != rs) {

try {

rs.close();

} catch (SQLException e) {

e.printStackTrace();

throw new RuntimeException(e);

}

}

}

public static void close(Statement stmt) {

if (null != stmt) {

try {

stmt.close();

} catch (SQLException e) {

e.printStackTrace();

throw new RuntimeException(e);

}

}

}

public static void close(Connection conn) {

if (null != conn) {

try {

conn.close();

} catch (SQLException e) {

e.printStackTrace();

throw new RuntimeException(e);

}

}

}

public static void myClose(Connection con,PreparedStatement ps,ResultSet rs) {

try {

if(rs!=null) {

rs.close();

}

if(ps!=null) {

ps.close();

}

if(con!=null&&!con.isClosed()) {

con.close();

}

} catch (Exception e) {

e.printStackTrace();

}

}

public static void close(Connection conn, Statement stmt, ResultSet rs) {

close(rs);

close(stmt);

close(conn);

}

public static boolean isOracle() {

return "oracle.jdbc.driver.OracleDriver".equals(driver);

}

public static boolean isSQLServer() {

return "com.microsoft.sqlserver.jdbc.SQLServerDriver".equals(driver);

}

public static boolean isMysql() {

return "com.mysql.jdbc.Driver".equals(driver);

}

public static void main(String[] args) {

Connection conn = DBHelper.getConnection();

DBHelper.close(conn);

System.out.println("isOracle：" + isOracle());

System.out.println("isSQLServer：" + isSQLServer());

System.out.println("isMysql：" + isMysql());

System.out.println("数据库连接(关闭)成功");

}

}

②config.peoperties

#oracle9i

#driver=oracle.jdbc.driver.OracleDriver

#url=jdbc:oracle:thin:@localhost:1521:ora9

#user=test

#pwd=test

#sql2005

#driver=com.microsoft.sqlserver.jdbc.SQLServerDriver

#url=jdbc:sqlserver://localhost:1423;DatabaseName=test

#user=sa

#pwd=sa

#sql2000

#driver=com.microsoft.jdbc.sqlserver.SQLServerDriver

#url=jdbc:microsoft:sqlserver://localhost:1433;databaseName=unit6DB

#user=sa

#pwd=888888

#mysql5

#driver=com.mysql.jdbc.Driver

#url=jdbc:mysql://127.0.0.1:3306/mybatis_ssm?useUnicode=true&characterEncoding=utf8&serverTimezone=GMT

#user=mybatis_ssm

#pwd=xiaoli

#mysql8

driver=com.mysql.cj.jdbc.Driver

url=jdbc:mysql://127.0.0.1:3306/t280?useUnicode=true&characterEncoding=utf8&serverTimezone=GMT&useSSL=true

user=root

pwd=123456

运行效果：

相关链接