如何使用JJWT及JWT讲解和工具类

{ "typ" : "JWT" , "alg" : "HS256" }

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iss: jwt签发者

sub: jwt所面向的用户

aud: 接收jwt的一方

exp: jwt的过期时间，这个过期时间必须要大于签发时间

nbf: 定义在什么时间之前，该jwt都是不可用的.

iat: jwt的签发时间

jti: jwt的唯一身份标识，主要用来作为一次性token,从而回避重放攻击。

{ "sub" : "1234567890" , "name" : "John Doe" , "admin" : true }

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< dependency >

     < groupId >io.jsonwebtoken</ groupId >

     < artifactId >jjwt</ artifactId >

     < version >0.9.0</ version >

</ dependency >

import com.sun.scenario.effect.impl.sw.sse.SSEBlend_SRC_OUTPeer;

import io.jsonwebtoken.Claims;

import io.jsonwebtoken.JwtBuilder;

import io.jsonwebtoken.Jwts;

import io.jsonwebtoken.SignatureAlgorithm;

import java.util.Date;

import java.util.HashMap;

public class TestJWT {

     public static void main(String[] args) {

         testCreateJWT();

         testParseJWT();

     }

     public static void testCreateJWT() {

         JwtBuilder builder = Jwts.builder()

                 .setId( "404" )                   // 设置唯一编号

                 .setSubject( "邢立豹" )            // 设置主题 可以是JSON数据

                 .setIssuedAt( new Date())        // 设置签发日期

                 // .setExpiration(new Date())      // 设置过期时间

                 // 设置签名 使用HS256算法 并设置SecretKey(字符串)

                 .signWith(SignatureAlgorithm.HS256, "LICHUN" );

         HashMap<String, Object> userInfo = new HashMap<>();

         userInfo.put( "name" , "枯木何日可逢春" );

         userInfo.put( "age" , "21" );

         builder.addClaims(userInfo);

         System.out.println(builder测试数据pact());

     }

     public static void testParseJWT() {

         String str = "eyJhbGciOiJIUzI1NiJ9.eyJqdGkiOiI0MDQiLCJzdWIiOiLpgqLnq4vosbkiLCJpYXQiOjE2MzA2ODAzNTMsImV4cCI6MTYzMDY4MDM1MywibmFtZSI6Iuaer-acqOS9leaXpeWPr-mAouaYpSIsImFnZSI6IjIxIn0.59i5xfLz9A-wTOJI9KxkF7zqp4zsLEWRC5DYlcy_Akc" ;

         Claims claims = Jwts.parser()

                 .setSigningKey( "LICHUN" )

                 .parseClaimsJws(str)

                 .getBody();

         System.out.println(claims);

     }

}

package com.lichun.utils;

import io.jsonwebtoken.Claims;

import io.jsonwebtoken.JwtBuilder;

import io.jsonwebtoken.Jwts;

import io.jsonwebtoken.SignatureAlgorithm;

import javax.crypto.SecretKey;

import javax.crypto.spec.SecretKeySpec;

import java.util.Base64;

import java.util.Date;

public class JWTUtil {

     // 有效期

     public static final Long JWT_TTL = 3600000L;

     // JWT令牌信息

     public static final String JWT_KEY = "LICHUN" ;

     public static String createJWT(String id, String subject, Long ttlMillis) {

         SignatureAlgorithm signatureAlgorithm = SignatureAlgorithm.HS256;

         long nowMillis = System.currentTimeMillis();

         Date now = new Date(nowMillis);

         if (ttlMillis == null ) {

             ttlMillis = JWT_TTL;

         }

         long expMillis = nowMillis + ttlMillis;

         Date expDate = new Date(expMillis);

         SecretKey secretKey = generalKey();

         JwtBuilder builder = Jwts.builder()

                 .setId(id)                      // 设置唯一编号

                 .setSubject(subject)            // 设置主题 可以是JSON数据

                 .setIssuer( "admin" )

                 .setIssuedAt(now)               // 设置签发日期

                 .setExpiration(expDate)         // 设置过期时间

                 // 设置签名 使用HS256算法 并设置SecretKey(字符串)

                 .signWith(SignatureAlgorithm.HS256, secretKey);

         return builder测试数据pact();

     }

     /**

      * 生成加密secretKey

      * @return

      */

     public static SecretKey generalKey() {

         byte [] encodedKey = Base64.getEncoder().encode(JWT_KEY.getBytes());

         SecretKey key = new SecretKeySpec(encodedKey, 0 , encodedKey.length, "AES" );

         return key;

     }

     /**

      * 解析令牌数据

      */

     public static Claims parseJWT(String jwt) throws Exception {

         SecretKey secretKey = generalKey();

         return Jwts.parser()

                 .setSigningKey(secretKey)

                 .parseClaimsJws(jwt)

                 .getBody();

     }

}