java开发jwt示例

pom文件引入

        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>2.15.1</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-core</artifactId>
            <version>2.15.1</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-annotations</artifactId>
            <version>2.15.1</version>
        </dependency>
        <dependency>
            <groupId>com.auth0</groupId>
            <artifactId>java-jwt</artifactId>
            <version>4.4.0</version>
        </dependency>

ras生成工具类

import java.security.spec.InvalidKeySpecException;
import java.util.Base64;
import javax.crypto.Cipher;
import java.security.KeyFactory;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;

/**
 * Java RSA 加密工具类
 *
 */
public class RSAUtils {

    /**
     * 密钥长度 于原文长度对应 以及越长速度越慢
     */
    private final static int KEY_SIZE = 1024;

    public static KeyPair createKeyPair(int size) throws NoSuchAlgorithmException {
        // KeyPairGenerator类用于生成公钥和私钥对，基于RSA算法生成对象
        KeyPairGenerator keyPairGen = KeyPairGenerator.getInstance("RSA");
        // 初始化密钥对生成器
        keyPairGen.initialize(Math.max(size, KEY_SIZE), new SecureRandom());
        // 生成一个密钥对，保存在keyPair中
        KeyPair keyPair = keyPairGen.generateKeyPair();
        return keyPair;
    }

    /**
     * 随机生成密钥对
     */
    public static String[] genKeyPair(int size) throws NoSuchAlgorithmException {
        KeyPair keyPair = createKeyPair(size);
        // 得到私钥
        RSAPrivateKey privateKey = (RSAPrivateKey) keyPair.getPrivate();
        // 得到公钥
        RSAPublicKey publicKey = (RSAPublicKey) keyPair.getPublic();
        String publicKeyString = Base64.getEncoder().encodeToString(publicKey.getEncoded());
        // 得到私钥字符串
        String privateKeyString = Base64.getEncoder().encodeToString(privateKey.getEncoded());
        // 将公钥和私钥保存到Map
        return new String[]{publicKeyString, privateKeyString};
    }

    public static RSAPublicKey toRSAPublicKey (String publicKey) throws NoSuchAlgorithmException, InvalidKeySpecException {
        byte[] decoded = Base64.getDecoder().decode(publicKey);
        return (RSAPublicKey) KeyFactory.getInstance("RSA").generatePublic(new X509EncodedKeySpec(decoded));
    }

    public static RSAPrivateKey toRSAPrivateKey (String privateKey) throws NoSuchAlgorithmException, InvalidKeySpecException {
        byte[] decoded = Base64.getDecoder().decode(privateKey);
        return  (RSAPrivateKey) KeyFactory.getInstance("RSA").generatePrivate(new PKCS8EncodedKeySpec(decoded));
    }

    /**
     * RSA公钥加密
     *
     * @param str    加密字符串
     * @param publicKey 公钥
     * @return 密文
     * @throws Exception 加密过程中的异常信息
     */
    public static String encrypt(String str, String publicKey) throws Exception {
        //base64编码的公钥
        byte[] decoded = Base64.getDecoder().decode(publicKey);
        RSAPublicKey pubKey = (RSAPublicKey) KeyFactory.getInstance("RSA").generatePublic(new X509EncodedKeySpec(decoded));
        //RSA加密
        Cipher cipher = Cipher.getInstance("RSA");
        cipher.init(Cipher.ENCRYPT_MODE, pubKey);
        String outStr = Base64.getEncoder().encodeToString(cipher.doFinal(str.getBytes("UTF-8")));
        return outStr;
    }

    /**
     * RSA私钥解密
     *
     * @param str    加密字符串
     * @param privateKey 私钥
     * @return 明文
     * @throws Exception 解密过程中的异常信息
     */
    public static String decrypt(String str, String privateKey) throws Exception {
        //64位解码加密后的字符串
        byte[] inputByte = Base64.getDecoder().decode(str);
        //base64编码的私钥
        byte[] decoded = Base64.getDecoder().decode(privateKey);
        RSAPrivateKey priKey = (RSAPrivateKey) KeyFactory.getInstance("RSA").generatePrivate(new PKCS8EncodedKeySpec(decoded));
        //RSA解密
        Cipher cipher = Cipher.getInstance("RSA");
        cipher.init(Cipher.DECRYPT_MODE, priKey);
        String outStr = new String(cipher.doFinal(inputByte));
        return outStr;
    }

}

示例

import com.auth0.jwt.JWT;
import com.auth0.jwt.algorithms.Algorithm;
import com.auth0.jwt.interfaces.DecodedJWT;
import com.auth0.jwt.interfaces.JWTVerifier;
import com.example.demo.util.RSAUtils;
import org.junit.jupiter.api.Test;

import java.security.NoSuchAlgorithmException;
import java.time.Instant;
import java.time.temporal.ChronoUnit;
import java.util.Arrays;

public class JWTTest {

    String[] keys;

    {
        try {
            keys = RSAUtils.genKeyPair(1024);
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        }
    }

    @Test
    public void test() {
        try {
            System.out.println(Arrays.toString(keys));
            Algorithm algorithm = Algorithm.RSA256(
                    RSAUtils.toRSAPublicKey(keys[0]),
                    RSAUtils.toRSAPrivateKey(keys[1]));
            String token = JWT.create()
                    .withIssuer("auth0")
                    .withExpiresAt(Instant.now().plus(1, ChronoUnit.DAYS))
                    .sign(algorithm);
            System.out.println(token);
            decodedJWT(algorithm, token);
        } catch (Exception e){
            e.printStackTrace();
        }
    }

    private void decodedJWT(Algorithm algorithm, String token) {
        DecodedJWT decodedJWT;
        try {
            JWTVerifier verifier = JWT.require(algorithm)
                    .withIssuer("auth0")
                    .build();
            decodedJWT = verifier.verify(token);
            System.out.println(decodedJWT.getPayload());
        } catch (Exception e){
            e.printStackTrace();
        }
    }

}