diff --git a/README.md b/README.md
index b5d9ddf..7106e74 100644
--- a/README.md
+++ b/README.md
@@ -115,6 +115,16 @@ CocoaTweet::API::API api(key);
 
 ```
 
+### NOTE
+if you want to call Twitter API using Bearer Token; OAuth2, you can do.
+```
+api.generateBearerToken();
+```
+After call it, always use Bearer Token to access API which kinds of GET method.  
+no affect to POST method.  
+then, if you use this, and ONLY use kind of GET API, you DO NOT need acess token.
+
+
 ## Use API
 ```
 // Post a tweet
diff --git a/api_key.json b/api_key.json
index 33be5e1..37865c0 100644
--- a/api_key.json
+++ b/api_key.json
@@ -1,6 +1,6 @@
 {
-    "consumer_key" : "ZppPUpvBAdG5pG1dXpmunKAWs",
-    "consumer_secret" : "eb8kIaw5xNFCjDkgATk3TmsehOnHhsNW1TCiOM2BK1zM0eOFrR",
-    "access_token" : "2224351076-elEMPKpQEwTRL9wphhqteU8zbjdMMqyMjkmRA2o",
-    "access_token_secret" : "0HiqIMPZwHwoM5cpawvNv5YSKYwEIYt7NXyeIoNfLqOMS"
+    "consumer_key" : "HmXS3q4yrQ2wndiCQzH8YnUQM",
+    "consumer_secret" : "qZwdGJYGFMpz7CSVGPHmbrh0O3Sk99wa0OLMf8HSvKKtNclrnf",
+    "access_token" : "1427931990792146949-iuNX8xBgQSXGtxr5cz8m495OtnXKcw",
+    "access_token_secret" : "A0R7vOOR3pRm4trGLxVbwNiQTkOMAkEh3z5ed3IxJVbJl"
 }
diff --git a/src/cocoatweet/api/interface/httpGet.cc b/src/cocoatweet/api/interface/httpGet.cc
index 663fd41..9699e2c 100644
--- a/src/cocoatweet/api/interface/httpGet.cc
+++ b/src/cocoatweet/api/interface/httpGet.cc
@@ -103,8 +103,9 @@ void HttpGet::process(std::weak_ptr<CocoaTweet::OAuth::OAuth1> _oauth,
     throw std::runtime_error(std::string("INTERNAL ERROR : curl(") + std::to_string(res) + ")");
     exit(1);
   }
-
+#ifndef NDEBUG
   std::cout << rcv << std::endl;
+#endif
   if ((responseCode / 100) == 4) {
     auto j       = nlohmann::json::parse(rcv);
     auto error   = j["errors"][0]["code"];
diff --git a/src/cocoatweet/api/interface/httpPost.cc b/src/cocoatweet/api/interface/httpPost.cc
index 10d4215..e318245 100644
--- a/src/cocoatweet/api/interface/httpPost.cc
+++ b/src/cocoatweet/api/interface/httpPost.cc
@@ -114,6 +114,9 @@ void HttpPost::process(std::weak_ptr<CocoaTweet::OAuth::OAuth1> _oauth,
     exit(1);
   }
 
+#ifndef NDEBUG
+  std::cout << rcv << std::endl;
+#endif
   if ((responseCode / 100) == 4) {
     auto j       = nlohmann::json::parse(rcv);
     auto error   = j["errors"][0]["code"];
diff --git a/src/main.cc b/src/main.cc
index 8487682..fdc0563 100644
--- a/src/main.cc
+++ b/src/main.cc
@@ -1,21 +1,6 @@
-#include "cocoatweet/oauth/key.h"
-#include "cocoatweet/api/api.h"
-#include <cocoatweet/api/directMessage/new.h>
-
+#include <cocoatweet/api/api.h>
 #include <iostream>
-#include <fstream>
-#include <algorithm>
-#include <unistd.h>
-#include <nlohmann/json.hpp>
-
 #include <cocoatweet/exception/exception.h>
-#include <cocoatweet/exception/rateLimitException.h>
-
-bool starts_with(const std::string& s, const std::string& prefix) {
-  auto size = prefix.size();
-  if (s.size() < size) return false;
-  return std::equal(std::begin(prefix), std::end(prefix), std::begin(s));
-}
 
 auto main() -> int {
   // Generate Key object
@@ -36,12 +21,16 @@ auto main() -> int {
 
   // if you want to access api using Bearer Token, call this for get BearerToken;
   // NOTE: call this, always authenticate with Bearer Token, which is Read Only Token
-  // api.generateBearerToken();
+  // try {
+    // api.generateBearerToken();
 
-  // Now, you can use a twitter api
-  // auto status = api.status().update("Hello Twitter World via Cocoa Twitter Library");
-  // api.favorite().create(status.id());
-  // api.favorite().destroy(status.id());
-  // api.status().destroy(status.id());
-  // auto timeline = api.status().userTimeline("milkcocoa0902");
+    // Now, you can use a twitter api
+    // auto status = api.status().update("Hello Twitter World via Cocoa Twitter Library");
+    // api.favorite().create(status.id());
+    // api.favorite().destroy(status.id());
+    // api.status().destroy(status.id());
+    // auto timeline = api.status().userTimeline("milkcocoa0902");
+  // } catch (CocoaTweet::Exception::Exception e) {
+  //   std::cout << e.what() << std::endl;
+  // }
 }