diff --git a/doc/class_diagram.puml b/doc/class_diagram.puml
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+@startuml
+package "net.micode.notes" {
+  package data {
+    class Notes {
+      +TYPE_NOTE
+      +TYPE_WIDGET_2X
+      +TYPE_WIDGET_4X
+    }
+    class NoteItemData {
+      +id
+      +snippet
+      +widgetId
+      +bgColorId
+    }
+  }
+
+  package widget {
+    abstract class NoteWidgetProvider {
+      #update()
+      #getLayoutId()
+      #getBgResourceId()
+      #getWidgetType()
+    }
+    class NoteWidgetProvider_2x
+    class NoteWidgetProvider_4x
+  }
+
+  package ui {
+    class NotesListActivity {
+      +onCreate()
+      +onListItemClick()
+    }
+    class NotesListItem
+  }
+
+  package tool {
+    class ResourceParser {
+      +WidgetBgResources
+    }
+  }
+}
+
+NoteWidgetProvider_2x --|> NoteWidgetProvider
+NoteWidgetProvider_4x --|> NoteWidgetProvider
+NoteWidgetProvider ..> ResourceParser
+NoteWidgetProvider ..> Notes
+NoteItemData ..> Notes
+DataUtils ..> Notes
+NotesListActivity ..> NoteItemData
+NotesListActivity ..> NotesListItem
+class DataUtils {
+  +batchDeleteNotes()
+  +moveNoteToFoler()
+  +batchMoveToFolder()
+  +getUserFolderCount()
+}
+class ContentResolver
+class ContentProviderOperation
+DataUtils --> ContentResolver
+DataUtils --> ContentProviderOperation
+@enduml
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diff --git a/doc/use_case_diagram.puml b/doc/use_case_diagram.puml
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+@startuml
+left to right direction
+actor 用户
+rectangle 笔记系统 {
+  用户 --> (创建笔记)
+  用户 --> (删除笔记)
+  用户 --> (移动笔记)
+  用户 --> (查看笔记)
+}
+@enduml
\ No newline at end of file
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