【Java工具类】建议使用Rsa加密JTW，贼安全！

工具类

引入依赖

  <dependency><groupId>io.jsonwebtokengroupId><artifactId>jjwtartifactId><version>0.9.0version>dependency><dependency><groupId>joda-timegroupId><artifactId>joda-timeartifactId><version>2.9.9version>dependency>

import io.jsonwebtoken.Claims;
import io.jsonwebtoken.Jws;
import io.jsonwebtoken.Jwts;
import io.jsonwebtoken.SignatureAlgorithm;
import org.joda.time.DateTime;import java.security.PrivateKey;
import java.security.PublicKey;/*** JWT工具类*/
public class JwtUtils {public static final String JWT_KEY_USERNAME = "username";public static final int EXPIRE_MINUTES = 120;/*** 私钥加密token*/public static String generateToken(String username, PrivateKey privateKey, int expireMinutes) {return Jwts.builder().claim(JWT_KEY_USERNAME, username).setExpiration(DateTime.now().plusMinutes(expireMinutes).toDate()).signWith(SignatureAlgorithm.RS256, privateKey).compact();}/*** 从token解析用户** @param token* @param publicKey* @return* @throws Exception*/public static String getUsernameFromToken(String token, PublicKey publicKey){Jws<Claims> claimsJws = Jwts.parser().setSigningKey(publicKey).parseClaimsJws(token);Claims body = claimsJws.getBody();String username = (String) body.get(JWT_KEY_USERNAME);return username;}
}

import java.io.File;
import java.io.IOException;
import java.nio.file.Files;
import java.security.*;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;/*** RSA工具类*/
public class RsaUtils {public static final String RSA_SECRET = "blbweb@#$%"; //秘钥public static final String RSA_PATH = System.getProperty("user.dir")+"/rsa/";//秘钥保存位置public static final String RSA_PUB_KEY_PATH = RSA_PATH + "pubKey.rsa";//公钥路径public static final String RSA_PRI_KEY_PATH = RSA_PATH + "priKey.rsa";//私钥路径public static PublicKey publicKey; //公钥public static PrivateKey privateKey; //私钥/*** 类加载后，生成公钥和私钥文件*/static {try {File rsa = new File(RSA_PATH);if (!rsa.exists()) {rsa.mkdirs();}File pubKey = new File(RSA_PUB_KEY_PATH);File priKey = new File(RSA_PRI_KEY_PATH);//判断公钥和私钥如果不存在就创建if (!priKey.exists() || !pubKey.exists()) {//创建公钥和私钥文件RsaUtils.generateKey(RSA_PUB_KEY_PATH, RSA_PRI_KEY_PATH, RSA_SECRET);}//读取公钥和私钥内容publicKey = RsaUtils.getPublicKey(RSA_PUB_KEY_PATH);privateKey = RsaUtils.getPrivateKey(RSA_PRI_KEY_PATH);} catch (Exception ex) {ex.printStackTrace();throw new RuntimeException(ex);}}/*** 从文件中读取公钥** @param filename 公钥保存路径，相对于classpath* @return 公钥对象* @throws Exception*/public static PublicKey getPublicKey(String filename) throws Exception {byte[] bytes = readFile(filename);return getPublicKey(bytes);}/*** 从文件中读取密钥** @param filename 私钥保存路径，相对于classpath* @return 私钥对象* @throws Exception*/public static PrivateKey getPrivateKey(String filename) throws Exception {byte[] bytes = readFile(filename);return getPrivateKey(bytes);}/*** 获取公钥** @param bytes 公钥的字节形式* @return* @throws Exception*/public static PublicKey getPublicKey(byte[] bytes) throws Exception {X509EncodedKeySpec spec = new X509EncodedKeySpec(bytes);KeyFactory factory = KeyFactory.getInstance("RSA");return factory.generatePublic(spec);}/*** 获取密钥** @param bytes 私钥的字节形式* @return* @throws Exception*/public static PrivateKey getPrivateKey(byte[] bytes) throws Exception {PKCS8EncodedKeySpec spec = new PKCS8EncodedKeySpec(bytes);KeyFactory factory = KeyFactory.getInstance("RSA");return factory.generatePrivate(spec);}/*** 根据密文，生存rsa公钥和私钥,并写入指定文件** @param publicKeyFilename  公钥文件路径* @param privateKeyFilename 私钥文件路径* @param secret             生成密钥的密文* @throws IOException* @throws NoSuchAlgorithmException*/public static void generateKey(String publicKeyFilename, String privateKeyFilename, String secret) throws Exception {KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA");SecureRandom secureRandom = new SecureRandom(secret.getBytes());keyPairGenerator.initialize(1024, secureRandom);KeyPair keyPair = keyPairGenerator.genKeyPair();// 获取公钥并写出byte[] publicKeyBytes = keyPair.getPublic().getEncoded();writeFile(publicKeyFilename, publicKeyBytes);// 获取私钥并写出byte[] privateKeyBytes = keyPair.getPrivate().getEncoded();writeFile(privateKeyFilename, privateKeyBytes);}private static byte[] readFile(String fileName) throws Exception {return Files.readAllBytes(new File(fileName).toPath());}private static void writeFile(String destPath, byte[] bytes) throws IOException {File dest = new File(destPath);if (!dest.exists()) {dest.createNewFile();}Files.write(dest.toPath(), bytes);}
}