基于Servlet实现博客系统--- 前后端分离
目录
一.博客系统概述
1.软件的生命周期
2.学习目标
二.数据库的建立
2.插入数据
三.创建项目
1.建立maven项目
2.导入相关的依赖
3.编写工具类
1.编写数据库相关的工具类
2.编写字符串的工具类
3.编写用户的工具类
4.创建实体类
1.创建user实体类
2.创建blog实体类
5.创建dao层(与数据库交互)
1.UserDao
1.实现登录功能
2.BlogDao
5.4测试DAO层
1.TestUserDao
2.TestBlogDao
5.5编写Common层
1.AppResult
2.AppConfig
6.创建servlet层
1.LoginServlet
2.UserServlet
3.BlogServlet
4.LogoutServlet
7.测试登录功能
1.测试登录接口
1.配置tomcat
2.使用postman测试登录接口
1.用户名为空校验
2.用户名不存在校验
3.密码错误校验
4.正确登录校验
编辑
2.测试用户接口
1.未登录状态
2.登录状态
3.测试博客接口
4.发布博客测试
8.导入前端页面
1.登录页面前端JS代码的实现
2.博客展示页面前端JS代码的实现
3.查看博客详细内容的js代码
4.编写发布博客的js代码
代码获取:基于Servlet实现博客系统--- 前后端分离: 基于Servlet实现博客系统--- 前后端分离
一.博客系统概述
1.软件的生命周期
- 可行性研究
- 需求分析—需求文档
- 概要设计
- 详细设计
- 开发
- 集成测试
- 验收测试
- 上线运行
- 维护
- 退役
2.学习目标
- 熟悉前端怎么发送数据
- 后端怎么接收数据
- 熟悉前后端交互过程中参数的解析方式(前后端要约定好)
- 后端接收到参数之后要做哪些校验
- 数据库如何操作
- 后端返回什么样的结果给前端
- 前端拿到服务器的响应之后做什么样的处理
二.数据库的建立
1.创建数据库和表
#设置数据库的编码集和排序忽略大小写
create database blog_db character set utf8mb4 collate utf8mb4_general_ci;
#建立user表
create table user(
id bigint primary key auto_increment comment '用户id,自增',
username varchar(50) unique not null comment '用户名',
password varchar(50) not null comment '密码'
);
#建立blog表
create table blog(
id bigint primary key auto_increment comment '博客id,自增',
title varchar(1024) not null comment '标题',
cotent text not null comment '内容',
createtime datetime not null comment '发布时间',
userid bigint comment '用户id',
foreign key (userid) references user(id)
);
insert into blog values(null,'我的铅笔','“铅笔，铅笔，5角一支呀!”，“橡皮5折啦，1元一块!”，还没进班，我就听到了这样的吆喝声，小学作文。
进了教室，只见桌椅摆成了柜台的形状，桌子上摆着各种各样的商品，琳琅满目。只见同学们有的在选购自己喜爱的商品，有的在边走边推销，说着：“只要是 想买，我可以给你打七折”，还有的坐在位子上吆喝着：“走过路过，不要错过,”“不看不知道，一看忘不掉!”看见这些情景，我也从书包中拿出我要卖的东 西。我卖的是一个神奇的魔术橡皮盒，它是天蓝色的，正面写着baby bear
魔术橡皮盒。为什么叫魔术橡皮盒呢?原来它可以变魔术，你把抽屉拉开时里面什么也没有，而当你把左侧一个开关推开，再打开抽屉时，里面便会出现一块精 致的小橡皮。这时周 走过来说：“赵越伟，我用这个小火车，小老鼠玩具和这个夹心饼换你的魔术橡皮盒可以吗?”我看了看他的小火车，很好玩，而且我们又是好朋友，于是便和他换 了。程博威这时也在吆喝：“可爱的小狗玩具呀!快来买呀!快来买呀!”我走过去跟他说：“我用这个小火车和你换行吗?”他说：“不行，这个别人已经有人定 购了。”这样的交易活动持续了很久，大家都很开心。
虽然我没有真正当过商人，可我已经感受到：“当商人真的不容易呀!只有想方设法吸引顾客，才能把自己的商品推销出去。”
',now(),1);
INSERT INTO blog VALUES(NULL,'测试1','测试内容',NOW(),2)
2.插入数据
#插入数据
insert into user values(null,'张三','123456'),(null,'李四','123456'); 
三.创建项目
1.建立maven项目
2.导入相关的依赖
javax.servlet
javax.servlet-api
3.1.0
mysql
mysql-connector-java
5.1.47
com.fasterxml.jackson.core
jackson-databind
2.15.2
3.编写工具类
1.编写数据库相关的工具类
采用单例模式创建数据库的工具类
package com.javastudy.utils;
import com.mysql.jdbc.jdbc2.optional.MysqlDataSource;
import javax.sql.DataSource;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
/**
* @author Chooker
* @create 2023-07-04 20:00
*/
public class DButils {
private static DataSource dataSource;
private static final String URL = "jdbc:mysql://localhost:13306/blog_db?characterEncoding=utf8&useSSL=false";
private static final String USER = "root";
private static final String PASSWORD = "woaini520";
//单例模式
private DButils() {
}
static {
MysqlDataSource mysqlDataSource = new MysqlDataSource();
mysqlDataSource.setURL(URL);
mysqlDataSource.setUser(USER);
mysqlDataSource.setPassword(PASSWORD);
dataSource = mysqlDataSource;
}
public static Connection getConnection() throws SQLException {
return dataSource.getConnection();
}
public static void close(ResultSet set, PreparedStatement statement, Connection connection) {
if (set != null) {
try {
set.close();
} catch (SQLException e) {
throw new RuntimeException(e);
}
}
if (statement != null) {
try {
statement.close();
} catch (SQLException e) {
throw new RuntimeException(e);
}
}
if (connection != null) {
try {
connection.close();
} catch (SQLException e) {
throw new RuntimeException(e);
}
}
}
}
2.编写字符串的工具类
package com.javastudy.utils;
/**
* @author Chooker
* @create 2023-07-04 20:35
*/
public class Stringutils {
/**
* 校验字符串是否为空
* @param value
* @return
*/
public static boolean isEmpty(String value) {
if (value == null || "".equals(value)) {
return true;
}
return false;
}
}
3.编写用户的工具类
package com.javastudy.utils;
import com.javastudy.common.AppConfig;
import com.javastudy.entities.User;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
/**
* @author Chooker
* @create 2023-07-06 21:29
*/
public class UserUtils {
public static User checkUserLoginStatus(HttpServletRequest req) {
//判断req对象是否为空
if (req == null) {
return null;
}
HttpSession session = req.getSession(false);
if (session == null) {
return null;
}
User user = (User) session.getAttribute(AppConfig.USER_SESSION_KEY);
return user;
}
}
4.创建实体类
1.创建user实体类
生成相对应的get和set方法和toString()方法(当然也可以使用lombok注解)
package com.javastudy.entities;
import com.fasterxml.jackson.annotation.JsonIgnore;
/**
* @author Chooker
* @create 2023-07-04 20:15
*/
public class User {
private Long id;
private String username;
@JsonIgnore //不参与json序列化
private String password;
private boolean isAuthor;
@Override
public String toString() {
return "User{" +
"id=" + id +
", username='" + username + '\'' +
", password='" + password + '\'' +
", isAuthor=" + isAuthor +
'}';
}
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public boolean isAuthor() {
return isAuthor;
}
public void setAuthor(boolean author) {
isAuthor = author;
}
public User() {
}
public User(Long id, String username, String password) {
this.id = id;
this.username = username;
this.password = password;
}
}
注意:最好在password上面加上JsonIgnore注解,这样在进行json序列化的时候,不会序列化password序列.加之前和之后的区别:可以看到密码没有进行json序列化
2.创建blog实体类
package com.javastudy.entities;
import java.sql.Timestamp;
/**
* @author Chooker
* @create 2023-07-04 20:17
*/
public class Blog {
private Long id;
private String title;
private String content;
private Timestamp createTime;
private Long userId;
@Override
public String toString() {
return "Blog{" +
"id=" + id +
", title='" + title + '\'' +
", content='" + content + '\'' +
", createTime=" + createTime +
", userId=" + userId +
'}';
}
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
public String getContent() {
return content;
}
public void setContent(String content) {
this.content = content;
}
public Timestamp getCreateTime() {
return createTime;
}
public void setCreateTime(Timestamp createTime) {
this.createTime = createTime;
}
public Long getUserId() {
return userId;
}
public void setUserId(Long userId) {
this.userId = userId;
}
public Blog(Long id, String title, String content, Timestamp createTime, Long userId) {
this.id = id;
this.title = title;
this.content = content;
this.createTime = createTime;
this.userId = userId;
}
public Blog() {
}
}
5.创建dao层(与数据库交互)
1.UserDao
1.实现登录功能
package com.javastudy.dao;
import com.javastudy.entities.User;
import com.javastudy.utils.DBUtils;
import com.javastudy.utils.StringUtils;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
/**
* @author Chooker
* @create 2023-07-04 20:33
*/
public class UserDao {
/**
* 根据用户名查询用户信息
*
* @param username
* @return
*/
public User selectByUsername(String username) {
//非空校验
if (StringUtils.isEmpty(username)) {
return null;
}
//进行数据库的查询操作
Connection connection = null;
PreparedStatement preparedStatement = null;
ResultSet resultSet = null;
try {
//1.获取数据库的连接
connection = DBUtils.getConnection();
//2.定义sql语句
String sql = "select * from user where username=?";
//3.对sql语句进行预处理
preparedStatement = connection.prepareStatement(sql);
//4.设置占位符的值
preparedStatement.setString(1, username);
//5.执行sql并获取结果
resultSet = preparedStatement.executeQuery();
//6.构建查询出来的user对象
if (resultSet.next()) {
User user = new User();
user.setId(resultSet.getLong(1));
user.setUsername(resultSet.getString(2));
user.setPassword(resultSet.getString(3));
return user;
}
} catch (SQLException e) {
throw new RuntimeException(e);
} finally {
DBUtils.close(resultSet, preparedStatement, connection);
}
return null;
}
/**
* 根据用户id查询用户信息
*
* @param id
* @return
*/
public User selectById(Long id) {
if (id == null || id < 0) {
return null;
}
//进行数据库的查询操作
Connection connection = null;
PreparedStatement preparedStatement = null;
ResultSet resultSet = null;
try {
connection = DBUtils.getConnection();
String sql = "select id,username,password from user where id=?";
preparedStatement = connection.prepareStatement(sql);
preparedStatement.setLong(1, id);
resultSet = preparedStatement.executeQuery();
if (resultSet.next()) {
User user = new User();
user.setId(resultSet.getLong(1));
user.setUsername(resultSet.getString(2));
user.setPassword(resultSet.getString(3));
return user;
}
} catch (SQLException e) {
throw new RuntimeException(e);
} finally {
DBUtils.close(resultSet, preparedStatement, connection);
}
return null;
}
}
2.BlogDao
package com.javastudy.dao;
import com.javastudy.entities.Blog;
import com.javastudy.utils.DBUtils;
import com.javastudy.utils.StringUtils;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
/**
* @author Chooker
* @create 2023-07-04 20:33
*/
public class BlogDao {
/**
* 查询所有的博客信息
*
* @return
*/
public List selectAll() {
Connection connection = null;
PreparedStatement preparedStatement = null;
ResultSet resultSet = null;
try {
connection = DBUtils.getConnection();
String sql = "select id,title,content,createTime,userId from blog order by createTime desc";
preparedStatement = connection.prepareStatement(sql);
List list = null;
resultSet = preparedStatement.executeQuery();
while (resultSet.next()) {
if (list == null) {
list = new ArrayList<>();
}
Blog blog = new Blog();
blog.setId(resultSet.getLong(1));
blog.setTitle(resultSet.getString(2));
blog.setContent(resultSet.getString(3));
blog.setCreateTime(resultSet.getTimestamp(4));
blog.setUserId(resultSet.getLong(5));
list.add(blog);
}
return list;
} catch (SQLException e) {
throw new RuntimeException(e);
} finally {
DBUtils.close(resultSet, preparedStatement, connection);
}
}
/**
* 根据博客id查询博客信息
*
* @param id
* @return
*/
public Blog selectById(Long id) {
if (id == null || id < 0) {
return null;
}
//进行数据库的查询操作
Connection connection = null;
PreparedStatement preparedStatement = null;
ResultSet resultSet = null;
try {
connection = DBUtils.getConnection();
String sql = "select id,title,content,createTime,userId from blog where id=?";
preparedStatement = connection.prepareStatement(sql);
preparedStatement.setLong(1, id);
resultSet = preparedStatement.executeQuery();
if (resultSet.next()) {
Blog blog = new Blog();
blog.setId(resultSet.getLong(1));
blog.setTitle(resultSet.getString(2));
blog.setContent(resultSet.getString(3));
blog.setCreateTime(resultSet.getTimestamp(4));
blog.setUserId(resultSet.getLong(5));
return blog;
}
} catch (SQLException e) {
throw new RuntimeException(e);
} finally {
DBUtils.close(resultSet, preparedStatement, connection);
}
return null;
}
/**
* 发布一篇博客
*
* @param blog
* @return 发布了多少条博客
*/
public int insert(Blog blog) {
if (blog == null || StringUtils.isEmpty(blog.getTitle()) || StringUtils.isEmpty(blog.getContent())
|| blog.getUserId() == null) {
return 0;
}
Connection connection = null;
PreparedStatement preparedStatement = null;
try {
connection = DBUtils.getConnection();
String sql = "insert into blog values(null,?,?,?,?)";
//预处理sql
preparedStatement = connection.prepareStatement(sql);
preparedStatement.setString(1, blog.getTitle());
preparedStatement.setString(2, blog.getContent());
preparedStatement.setTimestamp(3, blog.getCreateTime());
preparedStatement.setLong(4, blog.getUserId());
return preparedStatement.executeUpdate();
} catch (SQLException e) {
throw new RuntimeException(e);
} finally {
DBUtils.close(null, preparedStatement, connection);
}
}
}
5.4测试DAO层
1.TestUserDao
import com.javastudy.dao.UserDao;
import com.javastudy.entities.User;
import org.junit.Test;
/**
* @author Chooker
* @create 2023-07-06 21:12
*/
public class TestUser {
@Test
public void test01(){
UserDao userDao=new UserDao();
User user = userDao.selectByUsername("张三");
System.out.println(user);
}
}
2.TestBlogDao
import com.javastudy.dao.BlogDao;
import com.javastudy.entities.Blog;
import org.junit.Test;
import java.util.List;
/**
* @author Chooker
* @create 2023-07-06 21:05
*/
public class TestBlog {
@Test
public void test01(){
BlogDao blogDao = new BlogDao();
List blogs = blogDao.selectAll();
System.out.println(blogs);
}
}
5.5编写Common层
1.AppResult
package com.javastudy.common;
/**
* @author Chooker
* @create 2023-07-05 11:24
*/
public class AppResult {
//状态码
private Integer code;
//描述信息
private String message;
//相关数据
private T data;
public Integer getCode() {
return code;
}
public void setCode(Integer code) {
this.code = code;
}
public String getMessage() {
return message;
}
public void setMessage(String message) {
this.message = message;
}
public T getData() {
return data;
}
public void setData(T data) {
this.data = data;
}
public AppResult(Integer code, String message, T data) {
this.code = code;
this.message = message;
this.data = data;
}
public static AppResult success(T data) {
return new AppResult(0, "操作成功", data);
}
public static AppResult success(String message) {
return new AppResult(0, message, null);
}
public static AppResult success() {
return new AppResult(0, "操作成功", null);
}
public static AppResult fail(String message) {
return new AppResult(-1, message, null);
}
public static AppResult fail() {
return new AppResult(-1, "操作失败", null);
}
}
2.AppConfig
package com.javastudy.common;
/**
* @author Chooker
* @create 2023-07-05 17:37
*/
public class AppConfig {
public static final String USER_SESSION_KEY="USERSESSIONKEY";
}
6.创建servlet层
1.LoginServlet
package com.javastudy.servlet;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.javastudy.common.AppConfig;
import com.javastudy.common.AppResult;
import com.javastudy.dao.UserDao;
import com.javastudy.entities.User;
import com.javastudy.utils.Stringutils;
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 javax.servlet.http.HttpSession;
import java.io.IOException;
/**
* @author Chooker
* @create 2023-07-04 21:00
*/
@WebServlet("/login")
public class LoginServlet extends HttpServlet {
ObjectMapper objectMapper = new ObjectMapper();
UserDao userDao = new UserDao();
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
this.doPost(req, resp);
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
//设置编码集
req.setCharacterEncoding("utf-8");
resp.setContentType("application/json;charset=utf-8");
String username = req.getParameter("username");
String password = req.getParameter("password");
if (Stringutils.isEmpty(username) || Stringutils.isEmpty(password)) {
AppResult appResult = AppResult.fail("用户名或者密码为空");
resp.getWriter().write(objectMapper.writeValueAsString(appResult));
return;
}
User user = userDao.selectByUsername(username);
if (user == null) {
AppResult appResult = AppResult.fail("用户名不存在");
resp.getWriter().write(objectMapper.writeValueAsString(appResult));
return;
}
//验证密码是否错误
if (!user.getPassword().equals(password)) {
AppResult appResult = AppResult.fail("密码错误");
resp.getWriter().write(objectMapper.writeValueAsString(appResult));
return;
}
//登录成功 保存用户信息到session中
HttpSession session = req.getSession(true);
AppResult appResult = AppResult.success("登录成功");
//使用全局定义的sessionKey
session.setAttribute(AppConfig.USER_SESSION_KEY, user);
resp.getWriter().write(objectMapper.writeValueAsString(appResult));
}
}
2.UserServlet
package com.javastudy.servlet;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.javastudy.common.AppConfig;
import com.javastudy.common.AppResult;
import com.javastudy.dao.BlogDao;
import com.javastudy.dao.UserDao;
import com.javastudy.entities.Blog;
import com.javastudy.entities.User;
import com.javastudy.utils.StringUtils;
import com.javastudy.utils.UserUtils;
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 javax.servlet.http.HttpSession;
import java.io.IOException;
/**
* @author Chooker
* @create 2023-07-06 15:05
*/
@WebServlet("/user")
public class UserServlet extends HttpServlet {
private ObjectMapper objectMapper = new ObjectMapper();
private UserDao userDao = new UserDao();
private BlogDao blogDao = new BlogDao();
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
req.setCharacterEncoding("utf-8");
resp.setContentType("application/json;charset=utf-8");
HttpSession session = req.getSession(false);
//判断session
if (UserUtils.checkUserLoginStatus(req) == null) {
//设置状态码 403 表示用户没有权限
resp.setStatus(403);
//错误描述
AppResult appResult = AppResult.fail("用户没有登录,请登录后再试");
//代表用户没有登录
resp.getWriter().write(objectMapper.writeValueAsString(appResult));
return;
}
String blogId = req.getParameter("blogId");
String jsonStr = null;
if (StringUtils.isEmpty(blogId)) {
User user = (User) session.getAttribute(AppConfig.USER_SESSION_KEY);
jsonStr = objectMapper.writeValueAsString(AppResult.success(user));
} else {
Blog blog = blogDao.selectById(Long.valueOf(blogId));
if (blog == null) {
resp.getWriter().write(objectMapper.writeValueAsString(AppResult.fail("没有找到对应的博客")));
return;
}
User user = userDao.selectById(blog.getUserId());
jsonStr = objectMapper.writeValueAsString(AppResult.success(user));
}
//返回json
resp.getWriter().write(jsonStr);
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
super.doPost(req, resp);
}
}
3.BlogServlet
package com.javastudy.servlet;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.javastudy.common.AppResult;
import com.javastudy.dao.BlogDao;
import com.javastudy.entities.Blog;
import com.javastudy.entities.User;
import com.javastudy.utils.StringUtils;
import com.javastudy.utils.UserUtils;
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 javax.servlet.http.HttpSession;
import java.io.IOException;
import java.sql.Timestamp;
import java.time.LocalDateTime;
import java.util.ArrayList;
import java.util.List;
/**
* @author Chooker
* @create 2023-07-06 21:16
*/
@WebServlet("/blog")
public class BlogServlet extends HttpServlet {
BlogDao blogDao = new BlogDao();
ObjectMapper objectMapper = new ObjectMapper();
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
req.setCharacterEncoding("utf-8");
resp.setContentType("application/json;charset=utf-8");
//校验用户登录状态
HttpSession session = req.getSession(false);
//判断session
if (UserUtils.checkUserLoginStatus(req) == null) {
//设置状态码 403 表示用户没有权限
resp.setStatus(403);
//错误描述
AppResult appResult = AppResult.fail("用户没有登录,请登录后再试");
//代表用户没有登录
resp.getWriter().write(objectMapper.writeValueAsString(appResult));
return;
}
String blogId = req.getParameter("blogId");
String jsonStr = null;
if (StringUtils.isEmpty(blogId)) {
List blogs = blogDao.selectAll();
//非空的校验
if (blogs == null) {
blogs = new ArrayList<>();
}
jsonStr = objectMapper.writeValueAsString(AppResult.success(blogs));
} else {
Blog blog = blogDao.selectById(Long.valueOf(blogId));
if (blog == null) {
resp.getWriter().write(objectMapper.writeValueAsString(AppResult.fail("没有找到对应的博客")));
return;
}
jsonStr = objectMapper.writeValueAsString(AppResult.success(blog));
}
resp.getWriter().write(jsonStr);
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
req.setCharacterEncoding("utf-8");
resp.setContentType("application/json;charset=utf-8");
//校验用户登录状态
HttpSession session = req.getSession(false);
User user = UserUtils.checkUserLoginStatus(req);
//判断session
if (user == null) {
//设置状态码 403 表示用户没有权限
resp.setStatus(403);
//错误描述
AppResult appResult = AppResult.fail("用户没有登录,请登录后再试");
//代表用户没有登录
resp.getWriter().write(objectMapper.writeValueAsString(appResult));
return;
}
String title = req.getParameter("title");
String content = req.getParameter("content");
if (StringUtils.isEmpty(title) || StringUtils.isEmpty(content)) {
AppResult appResult = AppResult.fail("文章的标题或者内容为空");
//代表用户没有登录
resp.getWriter().write(objectMapper.writeValueAsString(appResult));
return;
}
Blog blog = new Blog();
blog.setTitle(title);
blog.setContent(content);
blog.setCreateTime(Timestamp.valueOf(LocalDateTime.now()));
blog.setUserId(user.getId());
int insert = blogDao.insert(blog);
if (insert <= 0) {
AppResult appResult = AppResult.fail("文章发布失败,请重新发布");
//代表用户没有登录
resp.getWriter().write(objectMapper.writeValueAsString(appResult));
return;
}
resp.getWriter().write(objectMapper.writeValueAsString(AppResult.success("发布成功")));
}
@Override
protected void doDelete(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
req.setCharacterEncoding("utf-8");
resp.setContentType("application/json;charset=utf-8");
//校验用户登录状态
HttpSession session = req.getSession(false);
User user = UserUtils.checkUserLoginStatus(req);
//判断session
if (user == null) {
//设置状态码 403 表示用户没有权限
resp.setStatus(403);
//错误描述
AppResult appResult = AppResult.fail("用户没有登录,请登录后再试");
//代表用户没有登录
resp.getWriter().write(objectMapper.writeValueAsString(appResult));
return;
}
String blogId = req.getParameter("blogId");
Blog blog = blogDao.selectById(Long.valueOf(blogId));
if (blog == null) {
resp.getWriter().write(objectMapper.writeValueAsString(AppResult.fail("不存在这个博客")));
return;
}
if (blog.getUserId() != user.getId()) {
resp.getWriter().write(objectMapper.writeValueAsString(AppResult.fail("无权删除别人的博客")));
return;
}
if (StringUtils.isEmpty(blogId)) {
resp.getWriter().write(objectMapper.writeValueAsString(AppResult.fail("参数校验失败")));
return;
}
//调用DAO进行删除操作
int row = blogDao.deleteById(Long.valueOf(blogId));
if (row != 1) {
resp.getWriter().write(objectMapper.writeValueAsString(AppResult.fail("删除失败")));
return;
}
resp.getWriter().write(objectMapper.writeValueAsString(AppResult.success("删除成功")));
}
}
4.LogoutServlet
package com.javastudy.servlet;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.javastudy.common.AppResult;
import com.javastudy.utils.UserUtils;
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 javax.servlet.http.HttpSession;
import java.io.IOException;
/**
* @author Chooker
* @create 2023-07-10 12:34
*/
@WebServlet("/logout")
public class LogoutServlet extends HttpServlet {
ObjectMapper objectMapper = new ObjectMapper();
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
req.setCharacterEncoding("utf-8");
resp.setContentType("application/json;charset=utf-8");
HttpSession session = req.getSession(false);
//判断session
if (UserUtils.checkUserLoginStatus(req) == null) {
//设置状态码 403 表示用户没有权限
resp.setStatus(403);
//错误描述
AppResult appResult = AppResult.fail("用户没有登录,请登录后再试");
//代表用户没有登录
resp.getWriter().write(objectMapper.writeValueAsString(appResult));
return;
}
if (session != null) {
session.invalidate();
}
resp.getWriter().write(objectMapper.writeValueAsString(AppResult.success("注销成功")));
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
super.doPost(req, resp);
}
}
7.测试登录功能
1.测试登录接口
1.配置tomcat
2.使用postman测试登录接口
1.用户名为空校验
符合代码的预期
2.用户名不存在校验
符合预期
3.密码错误校验
符合预期
4.正确登录校验
符合预期
2.测试用户接口
1.未登录状态
2.登录状态
3.测试博客接口
4.发布博客测试
发布博客成功.
8.导入前端页面
关于前段的html,css等信息可以到这个链接进行下载:
链接：https://pan.baidu.com/s/1BlLCsAzpN0szCsSEJYyF8Q?pwd=kvfu
提取码：kvfu
1.登录页面前端JS代码的实现
首先我们需要引入js的依赖
注意点:记得将表单的属性全部去掉,可以仅仅当这是一个标签,不需要表单的提交,这样会整个页面刷新,我们使用的是AJAX的局部提交技术,可以将form标签改为div标签也可以
其次就是我们需要将按钮的属性从submit改为button,如果不修改的话,当我们点击按钮的时候自动提交给本页面,刷新本页面,之前填的信息都没有了,一次仅仅是一个button即可,之后通过绑定click事件进行相关的操作.
2.博客展示页面前端JS代码的实现
3.查看博客详细内容的js代码
4.编写发布博客的js代码
三.部署并发布
1.购买服务器
购买服务器,可以从阿里云,腾讯云中购买服务器
选择centos
设置密码,购买即可
进入控制台,点击进入云服务器
点击即可进入服务器实例
2.配置服务器
通过xshell连接服务器,主机即为刚才买服务器的公网ip,只有有密码的验证,即为设置的自定义密码
登陆之后的页面
1.安装JDK
yum -y install java-1.8.0-openjdk.x86_64
注意:可通过Shift+insert复制到xshell中,有些笔记本电脑需要(Shift+Fn+insert)
通过以下命令验证是否安装成功,出现一下信息表示安装成功
java -version
2.安装数据库
安装mariadb服务
yum install -y mariadb-server
安装mariadb命令行客户端
yum install -y mariadb
安装mariadb C library
yum install -y mariadb-libs
安装mariadb开发包
yum install -y mariadb-devel
启动服务
systemctl start mariadb
设置服务开启自启动
systemctl enable mariadb
查看服务状态
systemctl status mariadb
active表示启动成功
安装成功之后可以正常连接服务器
语法与mysql一致
可以通过以下代码来进行设置密码和修改密码,默认没有密码
set password for 'root' @'localhost'=password('newpassword');
修改数据库的端口号:
vi /etc/my.cnf.d/server.cnf
重启数据库服务
systemctl restart mariadb
查看端口号:
show variables like 'port';
3.安装tomcat
下载 Tomcat 压缩包
通过官网进行下载: Apache Tomcat® - Apache Tomcat 8 Software Downloads
通过,下面的命令下载拖拽工具
yum -y install lrzsz
直接将压缩包拖拽到命令行
安装解压工具
yum -y install unzip
解压压缩包
unzip apache-tomcat-8.5.47.zi
此时表示解压成功
进入到tomcat的bin目录下,启动tomcat
chmmod +x ./*.sh (因为没有执行权限,所以先改权限)
./startup.sh (启动)
通过以下命令查询状态
netstat -anp | grep 8080
进入控制台配置安全规则
防火墙设置
查看防火墙状态(如果没开启,建议开启,不开启可以直接访问,开启了需要进行已下的操作访问)
systemctl status firewalld
启动防火墙和关闭防火墙
systemctl start firewalld
systemctl stop firewalld
查看开放的端口号
firewall-cmd --list-ports
开启8080端口
firewall-cmd --permanent --add-port=8080/tcp
重启防火墙
firewall-cmd --reload
设置开机启动
systemctl enable firewalld
访问地址:公网ip:8080,看到以下的画面表示tomcat开启成功
3.部署发布
将项目打为war包,拖拽到tomcat的webapps目录下
创建数据库
两种方式:第一种我们可以一点点复制粘贴sql语句到数据库中,一步一步的执行
第二种,我们可以将sql语句写到一个文件中,然后拖拽到一个目录下,然后执行以下的语句
source /root/java78/create.sql
此时即可
注意:需要将项目war包里面的设置与linux服务器中的配置一样,比如数据库的信息之类的.