生成公钥私钥：

/**
 * RSA 生成公钥私钥
 */
public class CreateSecrteKey {

    public static final String KEY_ALGORITHM = "RSA";
    private static final String PUBLIC_KEY = "RSAPublicKey";
    private static final String PRIVATE_KEY = "RSAPrivateKey";

    /**
     * 获取公钥
     * @param keyMap
     * @return
     * @throws Exception
     */
    public static String getPublicKey(Map<String, Object> keyMap) {
        // 获得map中的公钥对象 转为key对象
        Key key = (Key) keyMap.get(PUBLIC_KEY);
        // 编码返回字符串
        return encryptBASE64(key.getEncoded());
    }

    /**
     * 获取私钥
     * @param keyMap
     * @return
     * @throws Exception
     */
    public static String getPrivateKey(Map<String, Object> keyMap) {
        // 获得map中的私钥对象 转为key对象
        Key key = (Key) keyMap.get(PRIVATE_KEY);
        // 编码返回字符串
        return encryptBASE64(key.getEncoded());
    }

    /**
     * 解码返回byte
     * @param key
     * @return
     * @throws Exception
     */
    public static byte[] decryptBASE64(String key) throws Exception {
        return (new BASE64Decoder()).decodeBuffer(key);
    }

    /**
     * 编码返回字符串
     * @param key
     * @return
     * @throws Exception
     */
    public static String encryptBASE64(byte[] key) {
        return (new BASE64Encoder()).encodeBuffer(key);
    }

    /**
     * map对象中存放公私钥
     * @return
     * @throws Exception
     */
    public static Map<String, Object> initKey() throws Exception {
        // 获得对象 KeyPairGenerator 参数 RSA 1024个字节
        KeyPairGenerator keyPairGen = KeyPairGenerator.getInstance(KEY_ALGORITHM);
        keyPairGen.initialize(1024);
        // 通过对象 KeyPairGenerator 获取对象KeyPair
        KeyPair keyPair = keyPairGen.generateKeyPair();

        // 通过对象 KeyPair 获取RSA公私钥对象RSAPublicKey RSAPrivateKey
        RSAPublicKey publicKey = (RSAPublicKey) keyPair.getPublic();
        RSAPrivateKey privateKey = (RSAPrivateKey) keyPair.getPrivate();
        // 公私钥对象存入map中
        Map<String, Object> keyMap = new HashMap<>(2);
        keyMap.put(PUBLIC_KEY, publicKey);
        keyMap.put(PRIVATE_KEY, privateKey);
        return keyMap;
    }

    public static void main(String[] args) {
        Map<String, Object> keyMap;
        try {
            keyMap = initKey();
            String publicKey = getPublicKey(keyMap);
            System.out.println(publicKey);
            String privateKey = getPrivateKey(keyMap);
            System.out.println(privateKey);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

打印公钥私钥：

将生成的公钥私钥放在yml配置中：

配置类：

RSA工具类：

public class RsaUtil {
    /**
     * String to hold name of the encryption algorithm.
     */
    private static final String ALGORITHM = "RSA";

    private static final String CHAR_SET = "utf-8";

    private static final Logger logger = LoggerFactory.getLogger(RsaUtil.class);

    /**
     * Rsa encode string.
     *
     * @param publicCertificate the public certificate
     * @param text              the text
     * @return the string
     */
    public static String rsaEncode(String publicCertificate, String text) {
        try {
            byte[] publicBytes = baseStrToByte(publicCertificate);
            X509EncodedKeySpec keySpec = new X509EncodedKeySpec(publicBytes);
            KeyFactory keyFactory = KeyFactory.getInstance(ALGORITHM);
            PublicKey pubKey = keyFactory.generatePublic(keySpec);
            // get an RSA cipher object and print the provider
            final Cipher cipher = Cipher.getInstance(ALGORITHM);
            // encrypt the plain text using the public key
            cipher.init(Cipher.ENCRYPT_MODE, pubKey);
            byte[] cipherBytes = cipher.doFinal(text.getBytes(CHAR_SET));
            return baseByteToStr(cipherBytes);
        } catch (Exception e) {
            logger.error("publicCertificate:{}  \r\n  text:{}", publicCertificate, text, e);
        }
        return null;
    }


    /**
     * Rsa decode string.
     *
     * @param privateCertificate the private certificate
     * @param text               the text
     * @return the string
     */
    public static String rsaDecode(String privateCertificate, String text) {
        try {
            byte[] privateBytes = baseStrToByte(privateCertificate);
            PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(privateBytes);
            KeyFactory keyFactory = KeyFactory.getInstance(ALGORITHM);
            PrivateKey priKey = keyFactory.generatePrivate(keySpec);
            byte[] cipherText;
            // get an RSA cipher object and print the provider
            final Cipher cipher = Cipher.getInstance(ALGORITHM);
            // encrypt the plain text using the public key
            cipher.init(Cipher.DECRYPT_MODE, priKey);
            byte[] textbyte = baseStrToByte(text);
            cipherText = cipher.doFinal(textbyte);
            return new String(cipherText, CHAR_SET);
        } catch (Exception e) {
            logger.error("privateCertificate:{}  \r\n  text:{}", privateCertificate, text, e);
        }
        return null;
    }


    /**
     * @param str str
     * @return byte[]
     */
    private static byte[] baseStrToByte(String str) {
        return Base64.getDecoder().decode(str);
    }


    /**
     * @param bytes bytes
     * @return String
     */
    private static String baseByteToStr(byte[] bytes) {
        return Base64.getEncoder().encodeToString(bytes);
    }
}

使用：