diff --git a/components/educoder/course/course.js b/components/educoder/course/course.js
deleted file mode 100644
index f1916d1..0000000
--- a/components/educoder/course/course.js
+++ /dev/null
@@ -1,23 +0,0 @@
-// components/educoder/course/course.js
-Component({
-  /**
-   * 组件的属性列表
-   */
-  properties: {
-
-  },
-
-  /**
-   * 组件的初始数据
-   */
-  data: {
-
-  },
-
-  /**
-   * 组件的方法列表
-   */
-  methods: {
-    
-  }
-})
diff --git a/components/educoder/course/course.json b/components/educoder/course/course.json
deleted file mode 100644
index e8cfaaf..0000000
--- a/components/educoder/course/course.json
+++ /dev/null
@@ -1,4 +0,0 @@
-{
-  "component": true,
-  "usingComponents": {}
-}
\ No newline at end of file
diff --git a/components/educoder/course/course.wxml b/components/educoder/course/course.wxml
deleted file mode 100644
index e69de29..0000000
diff --git a/components/educoder/course/course.wxss b/components/educoder/course/course.wxss
deleted file mode 100644
index c088431..0000000
--- a/components/educoder/course/course.wxss
+++ /dev/null
@@ -1 +0,0 @@
-/* components/educoder/course/course.wxss */
\ No newline at end of file
diff --git a/components/modal/join_course/join_course.js b/components/modal/join_course/join_course.js
deleted file mode 100644
index 0f9cf2f..0000000
--- a/components/modal/join_course/join_course.js
+++ /dev/null
@@ -1,23 +0,0 @@
-// components/modal/join_course/join_course.js
-Component({
-  /**
-   * 组件的属性列表
-   */
-  properties: {
-
-  },
-
-  /**
-   * 组件的初始数据
-   */
-  data: {
-
-  },
-
-  /**
-   * 组件的方法列表
-   */
-  methods: {
-    
-  }
-})
diff --git a/components/modal/join_course/join_course.json b/components/modal/join_course/join_course.json
deleted file mode 100644
index e8cfaaf..0000000
--- a/components/modal/join_course/join_course.json
+++ /dev/null
@@ -1,4 +0,0 @@
-{
-  "component": true,
-  "usingComponents": {}
-}
\ No newline at end of file
diff --git a/components/modal/join_course/join_course.wxml b/components/modal/join_course/join_course.wxml
deleted file mode 100644
index dbfcd17..0000000
--- a/components/modal/join_course/join_course.wxml
+++ /dev/null
@@ -1,10 +0,0 @@
-<!--components/modal/join_course/join_course.wxml-->
-<modal id="modal" hidden="{{!show_join_course_modal}}" title="加入课堂" confirm-text="提交" cancel-text="取消" bindcancel="cancel_join_course_modal" bindconfirm="join_course">
-  <input type='text' bindinput="update_invite_code"  class="code-input" placeholder="邀请码" auto-focus/>
-  <checkbox-group bindchange="update_identities">
-      <text>身份：</text>
-      <lable class="identity"><checkbox value="professor"/>教师</lable>
-      <lable class="identity"><checkbox value="assistant_professor"/>助教</lable>
-      <lable class="identity"><checkbox value="student"/>学生</lable>
-  </checkbox-group>
-</modal>
diff --git a/components/modal/join_course/join_course.wxss b/components/modal/join_course/join_course.wxss
deleted file mode 100644
index daf1971..0000000
--- a/components/modal/join_course/join_course.wxss
+++ /dev/null
@@ -1,9 +0,0 @@
-.code-input{
-  border-radius: 10rpx;
-  border: 1rpx solid; 
-  height: 36px;
-  margin-bottom: 24rpx;
-}
-lable.identity{
-  margin-right: 16rpx;
-}
\ No newline at end of file
diff --git a/data/requests.js b/data/requests.js
index b2d908f..556469c 100644
--- a/data/requests.js
+++ b/data/requests.js
@@ -34,6 +34,7 @@ export class Session {
         if ("cookies" in res) {
           cookies = res["cookies"];
         } else if(res.header["Set-Cookie"]){
+          //@todo: better solution
           cookies = res.header["Set-Cookie"].replace(", ", "@@").replace(",","||").replace("@@",", ").split("||");
         }else{
           console.warn("request.js: no cookies setted in this request");
diff --git a/utils/pathutils.js b/utils/pathutils.js
index 0993d0d..de5c039 100644
--- a/utils/pathutils.js
+++ b/utils/pathutils.js
@@ -1,3 +1,5 @@
 /**
+ * 路径相关工具类
  * analyse url path to get info in order to navigate to the right page
+ * to be finished...
  */
\ No newline at end of file
diff --git a/utils/userutils.js b/utils/userutils.js
index e69de29..250f972 100644
--- a/utils/userutils.js
+++ b/utils/userutils.js
@@ -0,0 +1,4 @@
+/**
+ * 用户相关工具类
+ * to be finished...
+ */
\ No newline at end of file