java 采用RSA加密算法 采用的填充方式为：RSA/ECB/OAEPPadding

public static String decrypt(String str, String privateKey) throws Exception{
    //64位解码加密后的字符串
    byte[] inputByte = Base64.decodeBase64(str.getBytes("UTF-8"));
    //base64编码的私钥
    byte[] decoded = Base64.decodeBase64(privateKey);
    RSAPrivateKey priKey = (RSAPrivateKey) KeyFactory.getInstance("RSA").generatePrivate(new PKCS8EncodedKeySpec(decoded));
    //RSA解密
    Cipher cipher = Cipher.getInstance("RSA/ECB/OAEPPadding");
    cipher.init(Cipher.DECRYPT_MODE, priKey);
    String outStr = new String(cipher.doFinal(inputByte));
    return outStr;
}