diff --git a/src/helper/RSAUtils.java b/src/helper/RSAUtils.java
index 8a26ee3..4d817f4 100644
--- a/src/helper/RSAUtils.java
+++ b/src/helper/RSAUtils.java
@@ -7,12 +7,9 @@ import javax.crypto.BadPaddingException;
 import javax.crypto.Cipher;
 import javax.crypto.IllegalBlockSizeException;
 import java.io.IOException;
-import java.io.UnsupportedEncodingException;
+import java.nio.charset.StandardCharsets;
 import java.security.Key;
 import java.security.KeyFactory;
-import java.security.KeyPair;
-import java.security.KeyPairGenerator;
-import java.security.MessageDigest;
 import java.security.PrivateKey;
 import java.security.PublicKey;
 import java.security.spec.PKCS8EncodedKeySpec;
@@ -36,12 +33,8 @@ public class RSAUtils {
         if (StringUtils.isEmpty(plainText)) {
             return plainText;
         }
-        try {
-            byte[] publicEncrypt = encrypt(plainText.getBytes(EncodeConstants.ENCODING_UTF_8), publicKey);
-            return RSAUtils.byte2Base64(publicEncrypt);
-        } catch (UnsupportedEncodingException e) {
-            throw new RuntimeException(e);
-        }
+        byte[] publicEncrypt = encrypt(plainText.getBytes(StandardCharsets.UTF_8), publicKey);
+        return RSAUtils.byte2Base64(publicEncrypt);
     }
 
 
@@ -65,15 +58,9 @@ public class RSAUtils {
         if (bytes == null) {
             return null;
         }
-        try {
-            return new String(bytes, EncodeConstants.ENCODING_UTF_8);
-        } catch (UnsupportedEncodingException e) {
-            throw new RuntimeException(e);
-        }
+        return new String(bytes, StandardCharsets.UTF_8);
     }
 
-
-
     /**
      * RSA加密
      *
@@ -98,14 +85,7 @@ public class RSAUtils {
 
     private static byte[] dealEncryptFragment(byte[] data, Cipher cipher) throws IllegalBlockSizeException, BadPaddingException {
 
-        byte[] result = new byte[]{};
-        int i;
-        for (i = 0; i < data.length; i += FRAGMENT_LENGTH) {
-            byte[] fragment = ArrayUtils.subarray(data, i, i + FRAGMENT_LENGTH);
-            byte[] update = cipher.doFinal(fragment);
-            result = ArrayUtils.addAll(result, update);
-        }
-        return result;
+        return getBytes(data, cipher, FRAGMENT_LENGTH);
     }
 
 
@@ -130,100 +110,20 @@ public class RSAUtils {
 
     private static byte[] dealDecryptFragment(byte[] data, Cipher cipher) throws IllegalBlockSizeException, BadPaddingException {
 
+        return getBytes(data, cipher, FRAGMENT_LENGTH_DECRYPT);
+    }
+
+    private static byte[] getBytes(byte[] data, Cipher cipher, int fragmentLengthDecrypt) throws IllegalBlockSizeException, BadPaddingException {
         byte[] result = new byte[]{};
         int i;
-        for (i = 0; i < data.length; i += FRAGMENT_LENGTH_DECRYPT) {
-            byte[] fragment = ArrayUtils.subarray(data, i, i + FRAGMENT_LENGTH_DECRYPT);
+        for (i = 0; i < data.length; i += fragmentLengthDecrypt) {
+            byte[] fragment = ArrayUtils.subarray(data, i, i + fragmentLengthDecrypt);
             byte[] update = cipher.doFinal(fragment);
             result = ArrayUtils.addAll(result, update);
         }
         return result;
     }
 
-
-
-    public static String sha256(String plainTextData) {
-        if (StringUtils.isEmpty(plainTextData)) {
-            return plainTextData;
-        }
-        try {
-            byte[] bytes = sha256(plainTextData.getBytes(EncodeConstants.ENCODING_UTF_8));
-            return byteArrayToHexString(bytes);
-        } catch (UnsupportedEncodingException e) {
-            LoggerFactory.getLogger().error(e.getMessage(), e);
-        }
-        return plainTextData;
-    }
-
-    private static byte[] sha256(byte[] plainTextData) {
-        if (plainTextData == null || ArrayUtils.isEmpty(plainTextData)) {
-            return plainTextData;
-        }
-        try {
-            MessageDigest messageDigest = MessageDigest.getInstance("SHA-256");
-            messageDigest.update(plainTextData);
-            return  messageDigest.digest();
-        } catch (Exception e) {
-            LoggerFactory.getLogger().error(e.getMessage(), e);
-        }
-        return plainTextData;
-    }
-
-    /**
-     * 将加密后的字节数组转换成字符串
-     *
-     * @param b 字节数组
-     * @return 字符串
-     */
-    public static String byteArrayToHexString(byte[] b) {
-        StringBuilder hs = new StringBuilder();
-        String tempStr;
-        for (int n = 0; b != null && n < b.length; n++) {
-            tempStr = Integer.toHexString(b[n] & 0XFF);
-            if (tempStr.length() == 1)
-                hs.append('0');
-            hs.append(tempStr);
-        }
-        return hs.toString().toLowerCase();
-    }
-
-
-    /**
-     * 生成一个2048位的RSA秘钥对
-     *
-     * @return 秘钥对
-     * @throws Exception 如果无法生成秘钥对则抛出次异常
-     */
-    public static KeyPair getKeyPair() throws Exception {
-        KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA");
-        keyPairGenerator.initialize(2048);
-        return keyPairGenerator.generateKeyPair();
-    }
-
-    /**
-     * 获取RSA公钥的base64编码字符串
-     *
-     * @param keyPair 秘钥对
-     * @return 公钥编码字符串
-     */
-    public static String getPublicKey(KeyPair keyPair) {
-        PublicKey publicKey = keyPair.getPublic();
-        byte[] bytes = publicKey.getEncoded();
-        return byte2Base64(bytes);
-    }
-
-    /**
-     * 获取RSA私钥的base64编码字符串
-     *
-     * @param keyPair 秘钥对
-     * @return 私钥编码字符串
-     */
-    public static String getPrivateKey(KeyPair keyPair) {
-        PrivateKey privateKey = keyPair.getPrivate();
-        byte[] bytes = privateKey.getEncoded();
-        return byte2Base64(bytes);
-    }
-
     public static PublicKey string2PublicKey(String pubStr) {
         try {
             byte[] keyBytes = base642Byte(pubStr);
@@ -257,9 +157,4 @@ public class RSAUtils {
         BASE64Decoder decoder = new BASE64Decoder();
         return decoder.decodeBuffer(base64Key);
     }
-
-    public static void main(String... args) {
-
-    }
-
 }