1.数据库准备
create database whoere; //创建数据库 use whoere; create table email( //创建数据表，根据需要自行定义，比如基本的账号密码，我还设置了经纬度用于获取用户的位置 `id` int unsigned auto_increment, `account` varchar(20) not null, `password` varchar(20) not null, `Latitude` double, `Longitude` double, `Intention` varchar(100), primary key(`id`) )engine=InnoDB default charset=utf8;
设置模拟数据（随意）：
2.转战NetBeans(各种IDE都可以啦，比如Eclipse、Ij之类的)
安装过程我就不废话了，直接撸码！(需要用到的jar包也放在百度云了，记得导入库中哦)
首先是User类,都是基本的get和set函数。
package net.whoere;
/**
*
* @author SuSu
*/
public class User {
//账户（email)
private String account;
//密码
private String password;
//经度
private double Latitude;
//纬度
private double Longitude;
//意图
private String Intention;
public String getAccount() {
return account;
}
public void setAccount(String account) {
this.account = account;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public double getLatitude(){
return Latitude;
}
public void setLatitude(double Latitude){
this.Latitude = Latitude;
}
public double getLongitude(){
return Longitude;
}
public void setLongitude(double Longitude){
this.Longitude = Longitude;
}
public String getIntention(){
return Intention;
}
public void setIntention(String Intention){
this.Intention = Intention;
}
}
接着是DBManager类,实现数据库的连接与关闭。
package net.whoere;
/**
*
* @author SuSu
*/
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Statement;
import java.sql.ResultSet;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
public class DBManager extends HttpServlet {
ServletConfig config; //定义一个ServletConfig对象
private static String username; //定义数据库用户名
private static String password; //定义数据库连接密码
private static String url; //定义数据库连接URL
private static Connection connection; //定义连接
@Override
public void init(ServletConfig config) throws ServletException {
super.init(config); //继承父类的init()方法
this.config = config; //获取配置信息
username = config.getInitParameter("DBUsername"); //获取数据库用户名
password = config.getInitParameter("DBPassword"); //获取数据库连接密码
url = config.getInitParameter("ConnectionURL"); //获取数据库连接URL
}
//连接数据库
public static Connection getConnection() {
try {
Class.forName("com.mysql.jdbc.Driver").newInstance();
connection = DriverManager.getConnection(url, username, password);
} catch (ClassNotFoundException | InstantiationException
| IllegalAccessException | SQLException ex) {
Logger.getLogger(DBManager.class.getName()).log(Level.SEVERE, null, ex);
}
return connection;
}
//关闭连接，ResultSet是返回数据库的查询内容。
public static void closeAll(Connection connection, Statement statement,
ResultSet resultSet) {
try {
if (resultSet != null) {
resultSet.close();
}
if (statement != null) {
statement.close();
}
if (connection != null) {
connection.close();
}
} catch (SQLException ex) {
Logger.getLogger(DBManager.class.getName()).log(Level.SEVERE, null, ex);
}
}
//没有ResultSet的是关闭修改、增加数据操作（因为不用返回结果）
public static void closeAll(Connection connection, Statement statement) {
try {
if (statement != null) {
statement.close();
}
if (connection != null) {
connection.close();
}
} catch (SQLException ex) {
Logger.getLogger(DBManager.class.getName()).log(Level.SEVERE, null, ex);
}
}
}
UserDAO类
package net.whoere;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.HashMap;
import java.util.Map;
import java.util.logging.Level;
import java.util.logging.Logger;
import net.sf.json.JSONObject;
/**
*
* @author SuSu
*/
public class UserDAO {
//查询账户是否存在，存在返回具体User对象，否则为空。
public static User queryUser(String account) {
//连接数据库
Connection connection = DBManager.getConnection();
PreparedStatement preparedStatement = null;
ResultSet resultSet = null;
//SQL查询语句
StringBuilder sqlStatement = new StringBuilder();
sqlStatement.append("select * from email where account=?"); //问号？的地方会被account替换
//设置数据库的字段值
try {
preparedStatement = connection.prepareStatement(sqlStatement.toString());
preparedStatement.setString(1, account);
resultSet = preparedStatement.executeQuery(); //执行查找语句，获得返回信息
User user = new User();
if (resultSet.next()) { //生成User对象并返回
user.setAccount(resultSet.getString("account")); //设置账户、密码，根据返回的内容还可以设置其他信息
user.setPassword(resultSet.getString("password"));
return user;
} else {
return null;
}
} catch (SQLException ex) {
Logger.getLogger(UserDAO.class.getName()).log(Level.SEVERE, null, ex);
return null;
} finally {
DBManager.closeAll(connection, preparedStatement, resultSet); //关闭连接
}
}
//查询其他用户的信息，返回json格式，内容包括账号，位置，意图。
public static JSONObject queryUser() {
String sql1="select account,Latitude,Longitude,Intention from whoere.email"; //sql语句
Connection connection = DBManager.getConnection();
PreparedStatement preparedStatement = null;
Map<String, String> message = new HashMap<>();
JSONObject jsonObject = new JSONObject();
try {
preparedStatement = connection.prepareStatement(sql1);
} catch (SQLException ex) {
Logger.getLogger(UserDAO.class.getName()).log(Level.SEVERE, null, ex);
}
ResultSet resultSet = null;
try {
resultSet = preparedStatement.executeQuery();
for(int i = 1;resultSet.next();i++) {
message.put("account", resultSet.getString("account"));
message.put("Latitude", ""+resultSet.getDouble("Latitude"));
message.put("Longitude", ""+resultSet.getDouble("Longitude"));
message.put("Intention", resultSet.getString("Intention"));
jsonObject.put(i, message);
}
} catch (SQLException ex) {
Logger.getLogger(UserDAO.class.getName()).log(Level.SEVERE, null, ex);
}
DBManager.closeAll(connection, preparedStatement, resultSet);
return jsonObject;
}
//修改位置信息
public static void UpdateLocation(String account,String Latitude,String Longitude) {
Connection connection = DBManager.getConnection();
PreparedStatement preparedStatement = null;
//生成SQL代码
StringBuilder sqlStatement = new StringBuilder();
sqlStatement.append("update whoere.email set Latitude = ? ,Longitude = ? where account = ?");
//设置数据库的字段值
try {
preparedStatement = connection.prepareStatement(sqlStatement.toString());
preparedStatement.setString(1, Latitude);
preparedStatement.setString(2, Longitude);
preparedStatement.setString(3, account);
preparedStatement.executeUpdate();
} catch (SQLException ex) {
} finally {
DBManager.closeAll(connection, preparedStatement);
}
}
//实现注册账号功能(还有些问题！)
public static void Register(String account,String password){
//获得数据库的连接对象
Connection connection = DBManager.getConnection();
PreparedStatement preparedStatement = null;
//生成SQL代码
StringBuilder sqlStatement = new StringBuilder();
sqlStatement.append("insert into whoere.email (account,password) values (?,?)");
//设置数据库的字段值
try {
preparedStatement = connection.prepareStatement(sqlStatement.toString());
preparedStatement.setString(1, account);
preparedStatement.setString(2, password);
preparedStatement.executeUpdate();
} catch (SQLException ex) {
} finally {
DBManager.closeAll(connection, preparedStatement);
}
}
}
接着我们先建立一个LoginServlet吧，用于登录
package net.whoere;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.HashMap;
import java.util.Map;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import net.sf.json.JSONObject;
/**
*
* @author SuSu
*/
public class LoginServlet extends HttpServlet {
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
// 设置响应内容类型
response.setContentType("text/html;charset=utf-8");
request.setCharacterEncoding("utf-8");
response.setCharacterEncoding("utf-8");
try (PrintWriter out = response.getWriter()) {
//获得请求中传来的用户名和密码
String account = request.getParameter("account").trim();
String password = request.getParameter("password").trim();
//密码验证结果
Boolean verifyResult = verifyLogin(account, password);
Map<String, String> params = new HashMap<>();
JSONObject jsonObject = new JSONObject();
if (verifyResult) {
params.put("Result", "success");
} else {
params.put("Result", "failed");
}
jsonObject.put("params", params);
out.write(jsonObject.toString());
}
}
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doPost(request, response);
}
//验证用户名密码是否正确
private Boolean verifyLogin(String userName, String password) {
User user = UserDAO.queryUser(userName);
//账户密码验证
return null != user && password.equals(user.getPassword());
}
}
(持续更新中！)