1

data/SqlNote.java

@@ -0,0 +1,516 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package net.micode.notes.gtask.data;
+
+import android.appwidget.AppWidgetManager;
+import android.content.ContentResolver;
+import android.content.ContentValues;
+import android.content.Context;
+import android.database.Cursor;
+import android.net.Uri;
+import android.util.Log;
+
+import net.micode.notes.data.Notes;
+import net.micode.notes.data.Notes.DataColumns;
+import net.micode.notes.data.Notes.NoteColumns;
+import net.micode.notes.gtask.exception.ActionFailureException;
+import net.micode.notes.tool.GTaskStringUtils;
+import net.micode.notes.tool.ResourceParser;
+
+import org.json.JSONArray;
+import org.json.JSONException;
+import org.json.JSONObject;
+
+import java.util.ArrayList;
+
+//定义一个类，类名为SqlNote，作用：处理便签数据
+public class SqlNote {
+    //定义一个字符串，表示类名
+    private static final String TAG = SqlNote.class.getSimpleName();
+    //定义一个整型变量，表示无效ID
+    private static final int INVALID_ID = -99999;
+    //定义一个字符串数组，表示便签的列名
+    public static final String[] PROJECTION_NOTE = new String[] {
+            NoteColumns.ID, NoteColumns.ALERTED_DATE, NoteColumns.BG_COLOR_ID,
+            NoteColumns.CREATED_DATE, NoteColumns.HAS_ATTACHMENT, NoteColumns.MODIFIED_DATE,
+            NoteColumns.NOTES_COUNT, NoteColumns.PARENT_ID, NoteColumns.SNIPPET, NoteColumns.TYPE,
+            NoteColumns.WIDGET_ID, NoteColumns.WIDGET_TYPE, NoteColumns.SYNC_ID,
+            NoteColumns.LOCAL_MODIFIED, NoteColumns.ORIGIN_PARENT_ID, NoteColumns.GTASK_ID,
+            NoteColumns.VERSION
+    };
+    //定义一个整型变量，表示ID列
+    public static final int ID_COLUMN = 0;
+    //定义一个整型变量，表示提醒日期列
+    public static final int ALERTED_DATE_COLUMN = 1;
+    // 定义一个整型变量，表示背景颜色ID列
+    public static final int BG_COLOR_ID_COLUMN = 2;
+    //定义一个整型变量，表示创建日期列
+    public static final int CREATED_DATE_COLUMN = 3;
+    //定义一个整型变量，表示是否有附件列
+    public static final int HAS_ATTACHMENT_COLUMN = 4;
+    //定义一个整型变量，表示修改日期列
+    public static final int MODIFIED_DATE_COLUMN = 5;
+    //定义一个整型变量，表示便签数量列
+    public static final int NOTES_COUNT_COLUMN = 6;
+    //定义一个整型变量，表示父ID列
+    public static final int PARENT_ID_COLUMN = 7;
+    //定义一个整型变量，表示摘要列
+    public static final int SNIPPET_COLUMN = 8;
+    //定义一个整型变量，表示类型列
+    public static final int TYPE_COLUMN = 9;
+    //定义一个整型变量，表示小部件ID列
+    public static final int WIDGET_ID_COLUMN = 10;
+    //定义一个整型变量，表示小部件类型列
+    public static final int WIDGET_TYPE_COLUMN = 11;
+    //定义一个整型变量，表示同步ID列
+    public static final int SYNC_ID_COLUMN = 12;
+    //定义一个整型变量，表示本地修改列
+    public static final int LOCAL_MODIFIED_COLUMN = 13;
+    //定义一个整型变量，表示原始父ID列
+    public static final int ORIGIN_PARENT_ID_COLUMN = 14;
+    //定义一个整型变量，表示GTask ID列
+    public static final int GTASK_ID_COLUMN = 15;
+    //定义一个整型变量，表示版本列
+    public static final int VERSION_COLUMN = 16;
+    //定义一个上下文对象
+    private Context mContext;
+    //定义一个内容解析器对象
+    private ContentResolver mContentResolver;
+    //定义一个布尔型变量，表示是否创建
+    private boolean mIsCreate;
+
+    private long mId;
+
+    private long mAlertDate;
+
+    private int mBgColorId;
+
+    private long mCreatedDate;
+
+    private int mHasAttachment;
+
+    private long mModifiedDate;
+
+    private long mParentId;
+
+    private String mSnippet;
+
+    private int mType;
+
+    private int mWidgetId;
+
+    private int mWidgetType;
+
+    private long mOriginParent;
+
+    private long mVersion;
+
+    private ContentValues mDiffNoteValues;
+
+    private ArrayList<SqlData> mDataList;
+    //定义一个构造函数，参数为上下文对象 作用：初始化便签数据
+    public SqlNote(Context context) {
+        mContext = context;
+        mContentResolver = context.getContentResolver();
+        mIsCreate = true;
+        mId = INVALID_ID;
+        mAlertDate = 0;
+        mBgColorId = ResourceParser.getDefaultBgId(context);
+        mCreatedDate = System.currentTimeMillis();
+        mHasAttachment = 0;
+        mModifiedDate = System.currentTimeMillis();
+        mParentId = 0;
+        mSnippet = "";
+        mType = Notes.TYPE_NOTE;
+        mWidgetId = AppWidgetManager.INVALID_APPWIDGET_ID;
+        mWidgetType = Notes.TYPE_WIDGET_INVALIDE;
+        mOriginParent = 0;
+        mVersion = 0;
+        mDiffNoteValues = new ContentValues();
+        mDataList = new ArrayList<SqlData>();
+    }
+    //定义一个构造函数，参数为上下文对象和游标对象 作用：初始化便签数据
+    public SqlNote(Context context, Cursor c) {
+        mContext = context;
+        mContentResolver = context.getContentResolver();
+        mIsCreate = false;
+        loadFromCursor(c);
+        mDataList = new ArrayList<SqlData>();
+        if (mType == Notes.TYPE_NOTE)
+            loadDataContent();
+        mDiffNoteValues = new ContentValues();
+    }
+    //定义一个构造函数，参数为上下文对象和ID 作用：初始化便签数据
+    public SqlNote(Context context, long id) {
+        mContext = context;
+        mContentResolver = context.getContentResolver();
+        mIsCreate = false;
+        loadFromCursor(id);
+        mDataList = new ArrayList<SqlData>();
+        if (mType == Notes.TYPE_NOTE)
+            loadDataContent();
+        mDiffNoteValues = new ContentValues();
+
+    }
+    //定义一个方法，参数为JSONObject对象，返回值为布尔型 作用：设置便签内容
+    private void loadFromCursor(long id) {
+        Cursor c = null;
+        try {
+            c = mContentResolver.query(Notes.CONTENT_NOTE_URI, PROJECTION_NOTE, "(_id=?)",
+                    new String[] {
+                        String.valueOf(id)
+                    }, null);
+            if (c != null) {
+                c.moveToNext();
+                loadFromCursor(c);
+            } else {
+                Log.w(TAG, "loadFromCursor: cursor = null");
+            }
+        } finally {
+            if (c != null)
+                c.close();
+        }
+    }
+    //定义一个方法，参数为游标对象 作用：从游标中加载数据
+    private void loadFromCursor(Cursor c) {
+        mId = c.getLong(ID_COLUMN);
+        mAlertDate = c.getLong(ALERTED_DATE_COLUMN);
+        mBgColorId = c.getInt(BG_COLOR_ID_COLUMN);
+        mCreatedDate = c.getLong(CREATED_DATE_COLUMN);
+        mHasAttachment = c.getInt(HAS_ATTACHMENT_COLUMN);
+        mModifiedDate = c.getLong(MODIFIED_DATE_COLUMN);
+        mParentId = c.getLong(PARENT_ID_COLUMN);
+        mSnippet = c.getString(SNIPPET_COLUMN);
+        mType = c.getInt(TYPE_COLUMN);
+        mWidgetId = c.getInt(WIDGET_ID_COLUMN);
+        mWidgetType = c.getInt(WIDGET_TYPE_COLUMN);
+        mVersion = c.getLong(VERSION_COLUMN);
+    }
+    //定义一个方法，参数为游标对象 作用：从游标中加载数据
+    private void loadDataContent() {
+        Cursor c = null;
+        mDataList.clear();
+        try {
+            //查询数据表
+            c = mContentResolver.query(Notes.CONTENT_DATA_URI, SqlData.PROJECTION_DATA,
+                    "(note_id=?)", new String[] {
+                        String.valueOf(mId)
+                    }, null);
+            if (c != null) {//如果游标不为空，则遍历游标
+                if (c.getCount() == 0) {
+                    Log.w(TAG, "it seems that the note has not data");
+                    return;
+                }//如果游标的数量为0，则打印日志信息
+                while (c.moveToNext()) {
+                    SqlData data = new SqlData(mContext, c);
+                    mDataList.add(data);
+                }
+            } else { //如果游标为空，则打印日志信息
+                Log.w(TAG, "loadDataContent: cursor = null");
+            }
+        } finally {//关闭游标
+            if (c != null)
+                c.close();
+        }
+    }
+    //定义一个方法，参数为JSONObject对象，返回值为布尔型 作用：设置内容
+    public boolean setContent(JSONObject js) {
+        try {//捕获异常
+            JSONObject note = js.getJSONObject(GTaskStringUtils.META_HEAD_NOTE);
+            if (note.getInt(NoteColumns.TYPE) == Notes.TYPE_SYSTEM) {
+                Log.w(TAG, "cannot set system folder");
+            } else if (note.getInt(NoteColumns.TYPE) == Notes.TYPE_FOLDER) {
+                //对于文件夹，我们只能更新 snnipet 并键入
+                String snippet = note.has(NoteColumns.SNIPPET) ? note
+                        .getString(NoteColumns.SNIPPET) : "";
+                if (mIsCreate || !mSnippet.equals(snippet)) {
+                    mDiffNoteValues.put(NoteColumns.SNIPPET, snippet);
+                }
+                mSnippet = snippet;
+                //对于文件夹，我们只能更新类型
+                int type = note.has(NoteColumns.TYPE) ? note.getInt(NoteColumns.TYPE)
+                        : Notes.TYPE_NOTE;
+                //如果是创建或者类型不同，则将类型放入差异便签值中
+                if (mIsCreate || mType != type) {
+                    mDiffNoteValues.put(NoteColumns.TYPE, type);
+                }
+                mType = type;
+                //对于文件夹，我们只能更新小部件类型
+            } else if (note.getInt(NoteColumns.TYPE) == Notes.TYPE_NOTE) {
+                JSONArray dataArray = js.getJSONArray(GTaskStringUtils.META_HEAD_DATA);
+                long id = note.has(NoteColumns.ID) ? note.getLong(NoteColumns.ID) : INVALID_ID;
+                if (mIsCreate || mId != id) {
+                    mDiffNoteValues.put(NoteColumns.ID, id);
+                }
+                mId = id;
+                //如果是创建或者提醒日期不同，则将提醒日期放入差异便签值中
+                long alertDate = note.has(NoteColumns.ALERTED_DATE) ? note
+                        .getLong(NoteColumns.ALERTED_DATE) : 0;
+                if (mIsCreate || mAlertDate != alertDate) {
+                    mDiffNoteValues.put(NoteColumns.ALERTED_DATE, alertDate);
+                }
+                mAlertDate = alertDate;
+                //如果是创建或者背景颜色ID不同，则将背景颜色ID放入差异便签值中
+                int bgColorId = note.has(NoteColumns.BG_COLOR_ID) ? note
+                        .getInt(NoteColumns.BG_COLOR_ID) : ResourceParser.getDefaultBgId(mContext);
+                if (mIsCreate || mBgColorId != bgColorId) {
+                    mDiffNoteValues.put(NoteColumns.BG_COLOR_ID, bgColorId);
+                }
+                mBgColorId = bgColorId;
+                //如果是创建或者创建日期不同，则将创建日期放入差异便签值中
+                long createDate = note.has(NoteColumns.CREATED_DATE) ? note
+                        .getLong(NoteColumns.CREATED_DATE) : System.currentTimeMillis();
+                if (mIsCreate || mCreatedDate != createDate) {//如果是创建或者创建日期不同，则将创建日期放入差异便签值中
+                    mDiffNoteValues.put(NoteColumns.CREATED_DATE, createDate);
+                }
+                mCreatedDate = createDate;
+                //如果是创建或者是否有附件不同，则将是否有附件放入差异便签值中
+                int hasAttachment = note.has(NoteColumns.HAS_ATTACHMENT) ? note
+                        .getInt(NoteColumns.HAS_ATTACHMENT) : 0;
+                if (mIsCreate || mHasAttachment != hasAttachment) {
+                    mDiffNoteValues.put(NoteColumns.HAS_ATTACHMENT, hasAttachment);
+                }
+                mHasAttachment = hasAttachment;
+                //如果是创建或者修改日期不同，则将修改日期放入差异便签值中
+                long modifiedDate = note.has(NoteColumns.MODIFIED_DATE) ? note
+                        .getLong(NoteColumns.MODIFIED_DATE) : System.currentTimeMillis();
+                if (mIsCreate || mModifiedDate != modifiedDate) {
+                    mDiffNoteValues.put(NoteColumns.MODIFIED_DATE, modifiedDate);
+                }
+                mModifiedDate = modifiedDate;
+                //如果是创建或者父ID不同，则将父ID放入差异便签值中
+                long parentId = note.has(NoteColumns.PARENT_ID) ? note
+                        .getLong(NoteColumns.PARENT_ID) : 0;
+                if (mIsCreate || mParentId != parentId) {
+                    mDiffNoteValues.put(NoteColumns.PARENT_ID, parentId);
+                }
+                mParentId = parentId;
+                //如果是创建或者摘要不同，则将摘要放入差异便签值中
+                String snippet = note.has(NoteColumns.SNIPPET) ? note
+                        .getString(NoteColumns.SNIPPET) : "";
+                if (mIsCreate || !mSnippet.equals(snippet)) {
+                    mDiffNoteValues.put(NoteColumns.SNIPPET, snippet);
+                }
+                mSnippet = snippet;
+                //如果是创建或者类型不同，则将类型放入差异便签值中
+                int type = note.has(NoteColumns.TYPE) ? note.getInt(NoteColumns.TYPE)
+                        : Notes.TYPE_NOTE;
+                if (mIsCreate || mType != type) {
+                    mDiffNoteValues.put(NoteColumns.TYPE, type);
+                }
+                mType = type;
+                //如果是创建或者小部件ID不同，则将小部件ID放入差异便签值中
+                int widgetId = note.has(NoteColumns.WIDGET_ID) ? note.getInt(NoteColumns.WIDGET_ID)
+                        : AppWidgetManager.INVALID_APPWIDGET_ID;
+                if (mIsCreate || mWidgetId != widgetId) {
+                    mDiffNoteValues.put(NoteColumns.WIDGET_ID, widgetId);
+                }
+                mWidgetId = widgetId;
+                //如果是创建或者小部件类型不同，则将小部件类型放入差异便签值中
+                int widgetType = note.has(NoteColumns.WIDGET_TYPE) ? note
+                        .getInt(NoteColumns.WIDGET_TYPE) : Notes.TYPE_WIDGET_INVALIDE;
+                if (mIsCreate || mWidgetType != widgetType) {
+                    mDiffNoteValues.put(NoteColumns.WIDGET_TYPE, widgetType);
+                }
+                mWidgetType = widgetType;
+
+                long originParent = note.has(NoteColumns.ORIGIN_PARENT_ID) ? note
+                        .getLong(NoteColumns.ORIGIN_PARENT_ID) : 0;
+                if (mIsCreate || mOriginParent != originParent) {
+                    mDiffNoteValues.put(NoteColumns.ORIGIN_PARENT_ID, originParent);
+                }
+                mOriginParent = originParent;
+                //如果是创建或者GTask ID不同，则将GTask ID放入差异便签值中，否则将GTask ID放入差异便签值中
+                for (int i = 0; i < dataArray.length(); i++) {
+                    JSONObject data = dataArray.getJSONObject(i);
+                    SqlData sqlData = null;
+                    if (data.has(DataColumns.ID)) {
+                        long dataId = data.getLong(DataColumns.ID);
+                        for (SqlData temp : mDataList) {
+                            if (dataId == temp.getId()) {
+                                sqlData = temp;
+                            }
+                        }
+                    }
+                    //如果sqlData为空，则创建一个新的SqlData对象
+                    if (sqlData == null) {
+                        sqlData = new SqlData(mContext);
+                        mDataList.add(sqlData);
+                    }
+
+                    sqlData.setContent(data);
+                }
+            }
+            //捕获异常，打印异常信息作用：设置内容
+        } catch (JSONException e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+            return false;
+        }
+        return true;
+    }
+    //定义一个方法，返回JSONObject对象 作用：获取内容
+    public JSONObject getContent() {
+        try {
+            JSONObject js = new JSONObject();
+            //如果是创建，则打印日志信息
+            if (mIsCreate) {
+                Log.e(TAG, "it seems that we haven't created this in database yet");
+                return null;
+            }
+            //创建一个JSONObject对象
+            JSONObject note = new JSONObject();
+            if (mType == Notes.TYPE_NOTE) {
+                note.put(NoteColumns.ID, mId);
+                note.put(NoteColumns.ALERTED_DATE, mAlertDate);
+                note.put(NoteColumns.BG_COLOR_ID, mBgColorId);
+                note.put(NoteColumns.CREATED_DATE, mCreatedDate);
+                note.put(NoteColumns.HAS_ATTACHMENT, mHasAttachment);
+                note.put(NoteColumns.MODIFIED_DATE, mModifiedDate);
+                note.put(NoteColumns.PARENT_ID, mParentId);
+                note.put(NoteColumns.SNIPPET, mSnippet);
+                note.put(NoteColumns.TYPE, mType);
+                note.put(NoteColumns.WIDGET_ID, mWidgetId);
+                note.put(NoteColumns.WIDGET_TYPE, mWidgetType);
+                note.put(NoteColumns.ORIGIN_PARENT_ID, mOriginParent);
+                js.put(GTaskStringUtils.META_HEAD_NOTE, note);
+
+                JSONArray dataArray = new JSONArray();
+                for (SqlData sqlData : mDataList) {
+                    JSONObject data = sqlData.getContent();
+                    if (data != null) {
+                        dataArray.put(data);
+                    }
+                }
+                js.put(GTaskStringUtils.META_HEAD_DATA, dataArray);
+                //如果是文件夹，则打印日志信息
+            } else if (mType == Notes.TYPE_FOLDER || mType == Notes.TYPE_SYSTEM) {
+                note.put(NoteColumns.ID, mId);
+                note.put(NoteColumns.TYPE, mType);
+                note.put(NoteColumns.SNIPPET, mSnippet);
+                js.put(GTaskStringUtils.META_HEAD_NOTE, note);
+            }
+
+            return js;
+            //捕获异常，打印异常信息
+        } catch (JSONException e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+        }
+        return null;
+    }
+    //定义一个方法，返回JSONObject对象 作用：获取内容
+    public void setParentId(long id) {
+        mParentId = id;
+        mDiffNoteValues.put(NoteColumns.PARENT_ID, id);
+    }
+    //定义一个方法，返回JSONObject对象 作用：获取内容
+    public void setGtaskId(String gid) {
+        mDiffNoteValues.put(NoteColumns.GTASK_ID, gid);
+    }
+    //定义一个方法，返回JSONObject对象 作用：获取内容
+    public void setSyncId(long syncId) {
+        mDiffNoteValues.put(NoteColumns.SYNC_ID, syncId);
+    }
+    //定义一个方法，返回JSONObject对象 作用：获取内容
+    public void resetLocalModified() {
+        mDiffNoteValues.put(NoteColumns.LOCAL_MODIFIED, 0);
+    }
+
+    public long getId() {
+        return mId;
+    }
+
+    public long getParentId() {
+        return mParentId;
+    }
+
+    public String getSnippet() {
+        return mSnippet;
+    }
+
+    public boolean isNoteType() {
+        return mType == Notes.TYPE_NOTE;
+    }
+    //定义一个方法，返回布尔型 作用：是否是文件夹类型
+    public void commit(boolean validateVersion) {
+        if (mIsCreate) {//如果是创建，则打印日志信息
+            if (mId == INVALID_ID && mDiffNoteValues.containsKey(NoteColumns.ID)) {
+                mDiffNoteValues.remove(NoteColumns.ID);
+            }
+            //如果是创建，则插入数据
+            Uri uri = mContentResolver.insert(Notes.CONTENT_NOTE_URI, mDiffNoteValues);
+            try {//捕获异常，打印异常信息
+                mId = Long.valueOf(uri.getPathSegments().get(1));
+            } catch (NumberFormatException e) {
+                Log.e(TAG, "Get note id error :" + e.toString());
+                throw new ActionFailureException("create note failed");
+            }
+            if (mId == 0) {
+                throw new IllegalStateException("Create thread id failed");
+            }
+            //如果是便签类型，则插入数据
+            if (mType == Notes.TYPE_NOTE) {
+                for (SqlData sqlData : mDataList) {
+                    sqlData.commit(mId, false, -1);
+                }
+            }
+            //如果是文件夹类型，则打印日志信息
+        } else {
+            if (mId <= 0 && mId != Notes.ID_ROOT_FOLDER && mId != Notes.ID_CALL_RECORD_FOLDER) {
+                Log.e(TAG, "No such note");
+                throw new IllegalStateException("Try to update note with invalid id");
+            }
+            //如果是便签类型，则更新数据
+            if (mDiffNoteValues.size() > 0) {
+                mVersion ++;
+                int result = 0;
+                if (!validateVersion) {
+                    result = mContentResolver.update(Notes.CONTENT_NOTE_URI, mDiffNoteValues, "("
+                            + NoteColumns.ID + "=?)", new String[] {
+                        String.valueOf(mId)
+                    });
+                } else {
+                    //如果是便签类型，则更新数据
+                    result = mContentResolver.update(Notes.CONTENT_NOTE_URI, mDiffNoteValues, "("
+                            + NoteColumns.ID + "=?) AND (" + NoteColumns.VERSION + "<=?)",
+                            new String[] {
+                                    String.valueOf(mId), String.valueOf(mVersion)
+                            });
+                }
+                //如果结果为0，则打印日志信息
+                if (result == 0) {
+                    Log.w(TAG, "there is no update. maybe user updates note when syncing");
+                }
+            }
+            //如果是便签类型，则更新数据
+            if (mType == Notes.TYPE_NOTE) {
+                for (SqlData sqlData : mDataList) {
+                    sqlData.commit(mId, validateVersion, mVersion);
+                }
+            }
+        }
+        //如果是便签类型，则打印日志信息
+        // refresh local info
+        loadFromCursor(mId);
+        if (mType == Notes.TYPE_NOTE)
+            loadDataContent();
+        //如果是便签类型，则清空差异便签值
+        mDiffNoteValues.clear();
+        mIsCreate = false;
+    }
+}

data/Task.java

@@ -0,0 +1,368 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package net.micode.notes.gtask.data;
+
+import android.database.Cursor;
+import android.text.TextUtils;
+import android.util.Log;
+
+import net.micode.notes.data.Notes;
+import net.micode.notes.data.Notes.DataColumns;
+import net.micode.notes.data.Notes.DataConstants;
+import net.micode.notes.data.Notes.NoteColumns;
+import net.micode.notes.gtask.exception.ActionFailureException;
+import net.micode.notes.tool.GTaskStringUtils;
+
+import org.json.JSONArray;
+import org.json.JSONException;
+import org.json.JSONObject;
+
+//任务类，继承自Node类
+public class Task extends Node {
+    //定义一个字符串，表示任务类的简单名称
+    private static final String TAG = Task.class.getSimpleName();
+    //定义一个布尔型变量，表示任务是否已完成
+    private boolean mCompleted;
+
+    private String mNotes;
+
+    private JSONObject mMetaInfo;
+
+    private Task mPriorSibling;
+
+    private TaskList mParent;
+    //定义一个整型变量，表示同步操作为更新本地
+    public Task() {
+        super();
+        mCompleted = false;
+        mNotes = null;
+        mPriorSibling = null;
+        mParent = null;
+        mMetaInfo = null;
+    }
+    //定义一个整型变量，表示同步操作为更新本地
+    public JSONObject getCreateAction(int actionId) {
+        JSONObject js = new JSONObject();
+        // try catch语句，捕获异常
+        try {
+            // action_type
+            js.put(GTaskStringUtils.GTASK_JSON_ACTION_TYPE,
+                    GTaskStringUtils.GTASK_JSON_ACTION_TYPE_CREATE);
+            //
+            // action_id
+            js.put(GTaskStringUtils.GTASK_JSON_ACTION_ID, actionId);
+
+            // index
+            js.put(GTaskStringUtils.GTASK_JSON_INDEX, mParent.getChildTaskIndex(this));
+
+            // entity_delta
+            JSONObject entity = new JSONObject();
+            entity.put(GTaskStringUtils.GTASK_JSON_NAME, getName());
+            entity.put(GTaskStringUtils.GTASK_JSON_CREATOR_ID, "null");
+            entity.put(GTaskStringUtils.GTASK_JSON_ENTITY_TYPE,
+                    GTaskStringUtils.GTASK_JSON_TYPE_TASK);
+            // notes，作用：获取任务的备注
+            if (getNotes() != null) {
+                entity.put(GTaskStringUtils.GTASK_JSON_NOTES, getNotes());
+            }
+            // deleted，作用：获取任务是否已删除
+            js.put(GTaskStringUtils.GTASK_JSON_ENTITY_DELTA, entity);
+            // parent_id，作用：获取任务的父ID
+            js.put(GTaskStringUtils.GTASK_JSON_PARENT_ID, mParent.getGid());
+
+            // dest_parent_type
+            js.put(GTaskStringUtils.GTASK_JSON_DEST_PARENT_TYPE,
+                    GTaskStringUtils.GTASK_JSON_TYPE_GROUP);
+
+            // list_id
+            js.put(GTaskStringUtils.GTASK_JSON_LIST_ID, mParent.getGid());
+
+            // prior_sibling_id
+            if (mPriorSibling != null) {
+                js.put(GTaskStringUtils.GTASK_JSON_PRIOR_SIBLING_ID, mPriorSibling.getGid());
+            }
+
+        } catch (JSONException e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+            throw new ActionFailureException("fail to generate task-create jsonobject");
+        }
+
+        return js;
+    }
+    //定义一个整型变量，表示同步操作为更新本地
+    public JSONObject getUpdateAction(int actionId) {
+        JSONObject js = new JSONObject();
+        // try catch语句，捕获异常
+        try {
+            // action_type
+            js.put(GTaskStringUtils.GTASK_JSON_ACTION_TYPE,
+                    GTaskStringUtils.GTASK_JSON_ACTION_TYPE_UPDATE);
+
+            // action_id
+            js.put(GTaskStringUtils.GTASK_JSON_ACTION_ID, actionId);
+
+            // id
+            js.put(GTaskStringUtils.GTASK_JSON_ID, getGid());
+
+            // entity_delta
+            JSONObject entity = new JSONObject();
+            entity.put(GTaskStringUtils.GTASK_JSON_NAME, getName());
+            // notes，作用：获取任务的备注
+            if (getNotes() != null) {
+                entity.put(GTaskStringUtils.GTASK_JSON_NOTES, getNotes());
+            }
+            entity.put(GTaskStringUtils.GTASK_JSON_DELETED, getDeleted());
+            js.put(GTaskStringUtils.GTASK_JSON_ENTITY_DELTA, entity);
+        //捕获异常
+        } catch (JSONException e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+            throw new ActionFailureException("fail to generate task-update jsonobject");
+        }
+
+        return js;
+    }
+    //定义一个整型变量，表示同步操作为更新本地
+    public void setContentByRemoteJSON(JSONObject js) {
+        if (js != null) {
+            try {
+                // 获取任务的ID
+                if (js.has(GTaskStringUtils.GTASK_JSON_ID)) {
+                    setGid(js.getString(GTaskStringUtils.GTASK_JSON_ID));
+                }
+
+                // last_modified
+                // 获取任务的最后修改时间
+                if (js.has(GTaskStringUtils.GTASK_JSON_LAST_MODIFIED)) {
+                    setLastModified(js.getLong(GTaskStringUtils.GTASK_JSON_LAST_MODIFIED));
+                }
+
+                // name
+                // 获取任务的名称
+                if (js.has(GTaskStringUtils.GTASK_JSON_NAME)) {
+                    setName(js.getString(GTaskStringUtils.GTASK_JSON_NAME));
+                }
+
+                // notes
+                // 获取任务的备注
+                if (js.has(GTaskStringUtils.GTASK_JSON_NOTES)) {
+                    setNotes(js.getString(GTaskStringUtils.GTASK_JSON_NOTES));
+                }
+
+                // deleted
+                // 获取任务是否已删除
+                if (js.has(GTaskStringUtils.GTASK_JSON_DELETED)) {
+                    setDeleted(js.getBoolean(GTaskStringUtils.GTASK_JSON_DELETED));
+                }
+
+                // completed
+                // 获取任务是否已完成
+                if (js.has(GTaskStringUtils.GTASK_JSON_COMPLETED)) {
+                    setCompleted(js.getBoolean(GTaskStringUtils.GTASK_JSON_COMPLETED));
+                }
+            } catch (JSONException e) {
+                Log.e(TAG, e.toString());
+                e.printStackTrace();
+                throw new ActionFailureException("fail to get task content from jsonobject");
+            }
+        }
+    }
+    //定义一个整型变量，表示同步操作为更新本地
+    public void setContentByLocalJSON(JSONObject js) {
+        if (js == null || !js.has(GTaskStringUtils.META_HEAD_NOTE)
+                || !js.has(GTaskStringUtils.META_HEAD_DATA)) {
+            Log.w(TAG, "setContentByLocalJSON: nothing is avaiable");
+        }
+        // try catch语句，捕获异常
+        try {
+            JSONObject note = js.getJSONObject(GTaskStringUtils.META_HEAD_NOTE);
+            JSONArray dataArray = js.getJSONArray(GTaskStringUtils.META_HEAD_DATA);
+
+            if (note.getInt(NoteColumns.TYPE) != Notes.TYPE_NOTE) {
+                Log.e(TAG, "invalid type");
+                return;
+            }
+
+            for (int i = 0; i < dataArray.length(); i++) {
+                JSONObject data = dataArray.getJSONObject(i);
+                if (TextUtils.equals(data.getString(DataColumns.MIME_TYPE), DataConstants.NOTE)) {
+                    setName(data.getString(DataColumns.CONTENT));
+                    break;
+                }
+            }
+        //捕获异常
+        } catch (JSONException e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+            throw new ActionFailureException("fail to get task content from jsonobject");
+        } catch (JSONException e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+        }
+    }
+    //定义一个整型变量，表示同步操作为更新本地
+    public JSONObject getLocalJSONFromContent() {
+        String name = getName();
+        try {
+            if (mMetaInfo == null) {
+                // new task created from web
+                if (name == null) {
+                    Log.w(TAG, "the note seems to be an empty one");
+                    return null;
+                }
+                //创建一个JSONObject对象
+                JSONObject js = new JSONObject();
+                JSONObject note = new JSONObject();
+                JSONArray dataArray = new JSONArray();
+                JSONObject data = new JSONObject();
+                data.put(DataColumns.CONTENT, name);
+                dataArray.put(data);
+                js.put(GTaskStringUtils.META_HEAD_DATA, dataArray);
+                note.put(NoteColumns.TYPE, Notes.TYPE_NOTE);
+                js.put(GTaskStringUtils.META_HEAD_NOTE, note);
+                return js;
+            } else {
+
+               同步任务
+                JSONObject note = mMetaInfo.getJSONObject(GTaskStringUtils.META_HEAD_NOTE);
+                JSONArray dataArray = mMetaInfo.getJSONArray(GTaskStringUtils.META_HEAD_DATA);
+                //遍历JSONArray数组，获取数据
+                for (int i = 0; i < dataArray.length(); i++) {
+                    JSONObject data = dataArray.getJSONObject(i);
+                    if (TextUtils.equals(data.getString(DataColumns.MIME_TYPE), DataConstants.NOTE)) {
+                        data.put(DataColumns.CONTENT, getName());
+                        break;
+                    }
+                }
+                //创建一个JSONObject对象
+                note.put(NoteColumns.TYPE, Notes.TYPE_NOTE);
+                return mMetaInfo;
+            }
+        } catch (JSONException e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+            return null;
+        }
+    }
+    //定义一个整型变量，表示同步操作为更新本地
+    public void setMetaInfo(MetaData metaData) {
+        // try catch语句，捕获异常
+        if (metaData != null && metaData.getNotes() != null) {
+            try {
+                mMetaInfo = new JSONObject(metaData.getNotes());
+            } catch (JSONException e) {
+                Log.w(TAG, e.toString());
+                mMetaInfo = null;
+            }
+        }
+    }
+    //定义一个整型变量，表示同步操作为更新本地
+    public int getSyncAction(Cursor c) {
+        try {
+            JSONObject noteInfo = null;
+            //判断JSONObject对象是否为空
+            if (mMetaInfo != null && mMetaInfo.has(GTaskStringUtils.META_HEAD_NOTE)) {
+                noteInfo = mMetaInfo.getJSONObject(GTaskStringUtils.META_HEAD_NOTE);
+            }
+            //判断Cursor对象是否为空
+            if (noteInfo == null) {
+                Log.w(TAG, "it seems that note meta has been deleted");
+                return SYNC_ACTION_UPDATE_REMOTE;
+            }
+            //判断JSONObject对象是否包含指定的键
+            if (!noteInfo.has(NoteColumns.ID)) {
+                Log.w(TAG, "remote note id seems to be deleted");
+                return SYNC_ACTION_UPDATE_LOCAL;
+            }
+            //判断Cursor对象是否包含指定的列
+            // validate the note id now
+            if (c.getLong(SqlNote.ID_COLUMN) != noteInfo.getLong(NoteColumns.ID)) {
+                Log.w(TAG, "note id doesn't match");
+                return SYNC_ACTION_UPDATE_LOCAL;
+            }
+            //判断Cursor对象是否包含指定的列
+            if (c.getInt(SqlNote.LOCAL_MODIFIED_COLUMN) == 0) {
+                // there is no local update
+                if (c.getLong(SqlNote.SYNC_ID_COLUMN) == getLastModified()) {
+                    // no update both side
+                    return SYNC_ACTION_NONE;
+                } else {
+                    // apply remote to local
+                    return SYNC_ACTION_UPDATE_LOCAL;
+                }
+                //  Cursor对象是否包含指定的列
+            } else {
+                // validate gtask id
+                if (!c.getString(SqlNote.GTASK_ID_COLUMN).equals(getGid())) {
+                    Log.e(TAG, "gtask id doesn't match");
+                    return SYNC_ACTION_ERROR;
+                }
+                // Cursor对象是否包含指定的列，获取任务的最后修改时间
+                if (c.getLong(SqlNote.SYNC_ID_COLUMN) == getLastModified()) {
+                    // local modification only
+                    return SYNC_ACTION_UPDATE_REMOTE;
+                } else {
+                    return SYNC_ACTION_UPDATE_CONFLICT;
+                }
+            }
+        } catch (Exception e) {
+            Log.e(TAG, e.toString());
+            e.printStackTrace();
+        }
+
+        return SYNC_ACTION_ERROR;
+    }
+    //定义一个整型变量，表示同步操作为更新本地
+    public boolean isWorthSaving() {
+        return mMetaInfo != null || (getName() != null && getName().trim().length() > 0)
+                || (getNotes() != null && getNotes().trim().length() > 0);
+    }
+    //定义一个整型变量，表示同步操作为更新本地
+    public void setCompleted(boolean completed) {
+        this.mCompleted = completed;
+    }
+    //定义一个整型变量，表示同步操作为更新本地
+    public void setNotes(String notes) {
+        this.mNotes = notes;
+    }
+    //定义一个整型变量，表示同步操作为更新本地
+    public void setPriorSibling(Task priorSibling) {
+        this.mPriorSibling = priorSibling;
+    }
+    //定义一个整型变量，表示同步操作为更新本地
+    public void setParent(TaskList parent) {
+        this.mParent = parent;
+    }
+    //定义一个整型变量，表示同步操作为更新本地
+    public boolean getCompleted() {
+        return this.mCompleted;
+    }
+    //定义一个整型变量，表示同步操作为更新本地
+    public String getNotes() {
+        return this.mNotes;
+    }
+    //定义一个整型变量，表示同步操作为更新本地
+    public Task getPriorSibling() {
+        return this.mPriorSibling;
+    }
+    //定义一个整型变量，表示同步操作为更新本地
+    public TaskList getParent() {
+        return this.mParent;
+    }
+
+}