// 多行注释，说明版权信息和许可证 /* * 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. */ // 导入所需的类 package net.micode.notes.gtask.data; import android.content.ContentResolver; import android.content.ContentUris; 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.DataConstants; import net.micode.notes.data.Notes.NoteColumns; import net.micode.notes.data.NotesDatabaseHelper.TABLE; import net.micode.notes.gtask.exception.ActionFailureException; import org.json.JSONException; import org.json.JSONObject; // SqlData类用于处理与数据库相关的操作 public class SqlData { // 类的标签，用于日志记录 private static final String TAG = SqlData.class.getSimpleName(); // 定义一个无效的ID值 private static final int INVALID_ID = -99999; // 数据库查询的列 public static final String[] PROJECTION_DATA = new String[] { DataColumns.ID, DataColumns.MIME_TYPE, DataColumns.CONTENT, DataColumns.DATA1, DataColumns.DATA3 }; // 定义查询列的索引 public static final int DATA_ID_COLUMN = 0; public static final int DATA_MIME_TYPE_COLUMN = 1; public static final int DATA_CONTENT_COLUMN = 2; public static final int DATA_CONTENT_DATA_1_COLUMN = 3; public static final int DATA_CONTENT_DATA_3_COLUMN = 4; // 成员变量 private ContentResolver mContentResolver; // 内容解析器 private boolean mIsCreate; // 是否为创建操作 private long mDataId; // 数据ID private String mDataMimeType; // 数据MIME类型 private String mDataContent; // 数据内容 private long mDataContentData1; // 数据内容的DATA1字段 private String mDataContentData3; // 数据内容的DATA3字段 private ContentValues mDiffDataValues; // 与数据库不同的数据内容 // 构造函数，用于创建新的SqlData对象 public SqlData(Context context) { mContentResolver = context.getContentResolver(); mIsCreate = true; mDataId = INVALID_ID; mDataMimeType = DataConstants.NOTE; mDataContent = ""; mDataContentData1 = 0; mDataContentData3 = ""; mDiffDataValues = new ContentValues(); } // 构造函数，用于从数据库中加载现有的SqlData对象 public SqlData(Context context, Cursor c) { mContentResolver = context.getContentResolver(); mIsCreate = false; loadFromCursor(c); mDiffDataValues = new ContentValues(); } // 从游标加载数据 private void loadFromCursor(Cursor c) { mDataId = c.getLong(DATA_ID_COLUMN); mDataMimeType = c.getString(DATA_MIME_TYPE_COLUMN); mDataContent = c.getString(DATA_CONTENT_COLUMN); mDataContentData1 = c.getLong(DATA_CONTENT_DATA_1_COLUMN); mDataContentData3 = c.getString(DATA_CONTENT_DATA_3_COLUMN); } // 设置内容，从JSONObject中读取数据 public void setContent(JSONObject js) throws JSONException { long dataId = js.has(DataColumns.ID) ? js.getLong(DataColumns.ID) : INVALID_ID; if (mIsCreate || mDataId != dataId) { mDiffDataValues.put(DataColumns.ID, dataId); } mDataId = dataId; String dataMimeType = js.has(DataColumns.MIME_TYPE) ? js.getString(DataColumns.MIME_TYPE) : DataConstants.NOTE; if (mIsCreate || !mDataMimeType.equals(dataMimeType)) { mDiffDataValues.put(DataColumns.MIME_TYPE, dataMimeType); } mDataMimeType = dataMimeType; String dataContent = js.has(DataColumns.CONTENT) ? js.getString(DataColumns.CONTENT) : ""; if (mIsCreate || !mDataContent.equals(dataContent)) { mDiffDataValues.put(DataColumns.CONTENT, dataContent); } mDataContent = dataContent; long dataContentData1 = js.has(DataColumns.DATA1) ? js.getLong(DataColumns.DATA1) : 0; if (mIsCreate || mDataContentData1 != dataContentData1) { mDiffDataValues.put(DataColumns.DATA1, dataContentData1); } mDataContentData1 = dataContentData1; String dataContentData3 = js.has(DataColumns.DATA3) ? js.getString(DataColumns.DATA3) : ""; if (mIsCreate || !mDataContentData3.equals(dataContentData3)) { mDiffDataValues.put(DataColumns.DATA3, dataContentData3); } mDataContentData3 = dataContentData3; } // 获取内容，返回JSONObject public JSONObject getContent() throws JSONException { if (mIsCreate) { Log.e(TAG, "it seems that we haven't created this in database yet"); return null; } JSONObject js = new JSONObject(); js.put(DataColumns.ID, mDataId); js.put(DataColumns.MIME_TYPE, mDataMimeType); js.put(DataColumns.CONTENT, mDataContent); js.put(DataColumns.DATA1, mDataContentData1); js.put(DataColumns.DATA3, mDataContentData3); return js; } // 提交数据到数据库 public void commit(long noteId, boolean validateVersion, long version) { if (mIsCreate) { if (mDataId == INVALID_ID && mDiffDataValues.containsKey(DataColumns.ID)) { mDiffDataValues.remove(DataColumns.ID); } mDiffDataValues.put(DataColumns.NOTE_ID, noteId); Uri uri = mContentResolver.insert(Notes.CONTENT_DATA_URI, mDiffDataValues); try { mDataId = Long.valueOf(uri.getPathSegments().get(1)); } catch (NumberFormatException e) { Log.e(TAG, "Get note id error :" + e.toString()); throw new ActionFailureException("create note failed"); } } else { if (mDiffDataValues.size() > 0) { int result = 0; if (!validateVersion) { result = mContentResolver.update(ContentUris.withAppendedId( Notes.CONTENT_DATA_URI, mDataId), mDiffDataValues, null, null); } else { result = mContentResolver.update(ContentUris.withAppendedId( Notes.CONTENT_DATA_URI, mDataId), mDiffDataValues, " ? in (SELECT " + NoteColumns.ID + " FROM " + TABLE.NOTE + " WHERE " + NoteColumns.VERSION + "=?)", new String[] { String.valueOf(noteId), String.valueOf(version) }); } if (result == 0) { Log.w(TAG, "there is no update. maybe user updates note when syncing"); } } } mDiffDataValues.clear(); mIsCreate = false; } // 获取数据ID public long getId() { return mDataId; } }