第一步：创建项目
添加Maven依赖：
xml
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>fastjson</artifactId>
<version>1.2.62</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>io.jsonwebtoken</groupId>
<artifactId>jjwt-api</artifactId>
<version>0.11.2</version>
</dependency>
<dependency>
<groupId>io.jsonwebtoken</groupId>
<artifactId>jjwt-impl</artifactId>
<version>0.11.2</version>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>io.jsonwebtoken</groupId>
<artifactId>jjwt-jackson</artifactId>
<version>0.11.2</version>
<scope>runtime</scope>
</dependency>
<!-- 集成Thymeleaf-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>
<dependency>
<groupId>net.sourceforge.nekohtml</groupId>
<artifactId>nekohtml</artifactId>
<version>1.9.22</version>
</dependency>在resources/static目录下创建js文件夹，然后在其中添加jquery3.3.1.js文件
编辑application.yml：
javascript
server:
port: 80
servlet:
context-path: /jwt
spring:
thymeleaf:
#前缀，也就是模板存放的路径
prefix: classpath:/templates/
#编码格式
encoding: UTF-8
check-template-location: false
#关闭缓存，不然无法看到实时页面
cache: false
#后缀
suffix: .html
#设置不严格的html
mode: HTML
servlet:
content-type: text/html第二步：创建表示用户的实体类：
java
@Getter
@Setter
@ToString
@Builder
@AllArgsConstructor
@NoArgsConstructor
public class User implements Serializable {
private static final long serialVersionUID = -8390887042859558153L;
private Integer id;
private String username;
private String password;
}第三步：创建常量类：
java
public interface JwtConst {
//JWT签发者
String JWT_ID = "098f6bcd4621d373cade4e832627b4f6";
// 密钥, 经过Base64加密, 可自行替换
String JWT_SECRECT = "MDk4ZjZiY2Q0NjIxZD";
// 过期时间，单位毫秒
int JWT_TTL = 60*60*1000;
}第四步：Jwt工具类：
java
public class JwtUtil {
private static Key key = Keys.secretKeyFor(SignatureAlgorithm.HS256);
public static String createJWT(String id, String subject, int ttl) {
Calendar calendar = Calendar.getInstance();
JwtBuilder builder = Jwts.builder()
.setId(id) //JWT唯一标识
.setIssuedAt(calendar.getTime()) //签发时间
.setSubject(subject) //JWT的主题，比如JSON类型的User对象
.signWith(key);
calendar.add(Calendar.MINUTE, ttl); // ttl过期时间，单位分钟
builder.setExpiration(calendar.getTime()); //过期时间
return builder.compact();
}
public static Claims parseJwt(String jwt){
Claims claims = Jwts.parserBuilder().setSigningKey(key)
.build().parseClaimsJws(jwt).getBody();
return claims;
}
public static String createSubject(User user){
return JSON.toJSONString(user);
}
}第五步：创建表示服务器端返回结果的类：
java
@Data
@NoArgsConstructor
@AllArgsConstructor
public class Result<T> {
private int code;
private String msg;
private T data;
public Result(int code, String msg) {
this.code = code;
this.msg = msg;
}
}第六步：创建Controller：
生成、解析JWT的Controller
java
@Controller
@RequestMapping("/jwt")
public class JWTController {
@RequestMapping("/login")
@ResponseBody
public Result<String> login(String username, String password) {
if (username == null || password == null) {
return new Result<String>(789, "用户名或密码不正确", null);
}
User user = new User(1001, username, password);
String jwt = JwtUtil.createJWT(JwtConst.JWT_ID,
JwtUtil.createSubject(user), JwtConst.JWT_TTL);
System.out.println(jwt);
return new Result<>(200, "请求成功！", jwt);
}
@RequestMapping("/parseJwt")
@ResponseBody
public User parseJwt(HttpServletRequest request) {
String jwt = request.getHeader("Authorization");
String token = JSON.parseObject(jwt).getString("token");
Claims claims = JwtUtil.parseJwt(token);
String subject = claims.getSubject();
User user = JSON.parseObject(subject, User.class);
System.out.println(user);
return user;
}
}页面分发的Controller：
java
@Controller
public class DispatchController {
@GetMapping("/login")
public String showLogin(){
return "/login";
}
@GetMapping("/showJwt")
public String showJwt(){
return "showJwt";
}
@GetMapping("/index")
public String index(){
return "index";
}
}第七步：前端页面：
login.html
html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>登录页面</title>
<script src="js/jquery3.5.1.js" type="text/javascript"></script>
</head>
<body>
<form id="loginForm">
<input type="text" name="username" value="zhangsan"><br>
<input type="password" name="password" value="123456">
</form>
<button id="btn">登录</button>
<script>
$(function () {
$("#btn").click(function () {
$.ajax({
type: "POST",//请求方式
url: "jwt/login", //请求地址
dataType: "JSON", //预期服务器端返回的数据的类型
data: $("#loginForm").serialize(),//数据，json字符串
success: function (result) { //请求成功
console.log(result);
if (result.code == 200) {
//获取令牌并保存到本地
localStorage.setItem("token", '{"token":"' + result.data + '"}');
}
if (result.code == 789) {
window.location = "login";
}
},
error: function (e) { //请求失败，包含具体的错误信息
console.log(e.status);
console.log(e.responseText);
}
});
});
});
</script>
</body>
</html>注：第一次点登录按钮时，无法将token数据保存在Application中，原因未找到，发现原因的朋友麻烦告诉我一声。
index.html
html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>首页</title>
<script src="js/jquery3.3.1.js" type="text/javascript"></script>
</head>
<body>
首页启动时请求后台的解析Jwt的的请求
<div id="sh"></div>
<script>
$(function () {
$.ajax({
url: "jwt/parseJwt",
headers: {Authorization: localStorage.getItem("token")},
success:function (res) {
console.info(res);
$("#sh").text(JSON.stringify(res));
}
})
});
</script>
</body>
</html>第八步：部署运行查看结果：
注：第一次点登录按钮时，无法将token数据保存在Application中，原因未找到。
