data/Contact.java和data/Notes.java的注释

notes/data/Contact.java

@@ -25,46 +25,51 @@ import android.util.Log;
 
 import java.util.HashMap;
 
-public class Contact {
+public class Contact {//联系人
     private static HashMap<String, String> sContactCache;
     private static final String TAG = "Contact";
-
+     //定义字符串CALLER_ID_SELECTION
     private static final String CALLER_ID_SELECTION = "PHONE_NUMBERS_EQUAL(" + Phone.NUMBER
     + ",?) AND " + Data.MIMETYPE + "='" + Phone.CONTENT_ITEM_TYPE + "'"
     + " AND " + Data.RAW_CONTACT_ID + " IN "
             + "(SELECT raw_contact_id "
             + " FROM phone_lookup"
             + " WHERE min_match = '+')";
-
+    //获取联系人
     public static String getContact(Context context, String phoneNumber) {
         if(sContactCache == null) {
             sContactCache = new HashMap<String, String>();
         }
-
+        //查找HasMap中是否有phoneNumber信息
         if(sContactCache.containsKey(phoneNumber)) {
             return sContactCache.get(phoneNumber);
         }
 
         String selection = CALLER_ID_SELECTION.replace("+",
                 PhoneNumberUtils.toCallerIDMinMatch(phoneNumber));
+        //查找数据库中phoneNumber的信息
         Cursor cursor = context.getContentResolver().query(
                 Data.CONTENT_URI,
                 new String [] { Phone.DISPLAY_NAME },
                 selection,
                 new String[] { phoneNumber },
                 null);
-
+        //判定查询结果
+        //moveToFirst()返回第一条
         if (cursor != null && cursor.moveToFirst()) {
             try {
+                //找到相关信息
                 String name = cursor.getString(0);
                 sContactCache.put(phoneNumber, name);
                 return name;
+            //异常
             } catch (IndexOutOfBoundsException e) {
                 Log.e(TAG, " Cursor get string error " + e.toString());
                 return null;
             } finally {
                 cursor.close();
             }
+            //未找到相关信息
         } else {
             Log.d(TAG, "No contact matched with number:" + phoneNumber);
             return null;

notes/data/Notes.java

@@ -17,9 +17,11 @@
 package net.micode.notes.data;
 
 import android.net.Uri;
+//Notes 类中定义了很多变量，这些常量大多都是int型和string型
 public class Notes {
     public static final String AUTHORITY = "micode_notes";
     public static final String TAG = "Notes";
+    //以下三个常量对NoteColumns.TYPE的值进行设置时会用到
     public static final int TYPE_NOTE     = 0;
     public static final int TYPE_FOLDER   = 1;
     public static final int TYPE_SYSTEM   = 2;
@@ -54,13 +56,15 @@ public class Notes {
     /**
      * Uri to query all notes and folders
      */
+    //定义查询便签和文件夹的指针
     public static final Uri CONTENT_NOTE_URI = Uri.parse("content://" + AUTHORITY + "/note");
 
     /**
      * Uri to query data
      */
+    //定义查找数据的指针
     public static final Uri CONTENT_DATA_URI = Uri.parse("content://" + AUTHORITY + "/data");
-
+    //定义NoteColumns的常量，用于后面创建数据库的表头
     public interface NoteColumns {
         /**
          * The unique ID for a row
@@ -166,7 +170,7 @@ public class Notes {
          */
         public static final String VERSION = "version";
     }
-
+    //定义DateColumns的常量，用于后面创建数据库的表头
     public interface DataColumns {
         /**
          * The unique ID for a row
@@ -239,7 +243,7 @@ public class Notes {
          * <P> Type: TEXT </P>
          */
         public static final String DATA5 = "data5";
-    }
+    } //主要是定义存储便签内容数据的
 
     public static final class TextNote implements DataColumns {
         /**
@@ -255,7 +259,7 @@ public class Notes {
         public static final String CONTENT_ITEM_TYPE = "vnd.android.cursor.item/text_note";
 
         public static final Uri CONTENT_URI = Uri.parse("content://" + AUTHORITY + "/text_note");
-    }
+    }//文本内容的数据结构
 
     public static final class CallNote implements DataColumns {
         /**
@@ -275,5 +279,5 @@ public class Notes {
         public static final String CONTENT_ITEM_TYPE = "vnd.android.cursor.item/call_note";
 
         public static final Uri CONTENT_URI = Uri.parse("content://" + AUTHORITY + "/call_note");
-    }
+    }//电话内容的数据结构
 }