p3o5nagmu
/
note
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

ADD file via upload

Browse Source
shenyifei
p3o5nagmu 8 months ago
parent 5c74cd3f81
commit 42f2022107
1 changed files with 199 additions and 0 deletions
Show Stats Download Patch File Download Diff File

199
SqlData.java
Unescape View File

@ -0,0 +1,199 @@
/*
* 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.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，可能用于处理与数据库相关的数据操作，比如从数据库读取数据、将数据更新到数据库以及和JSON数据的相互转换等
public class SqlData {
// 用于日志记录的标签，使用类的简单名称，方便在日志中识别该类相关的输出信息
private static final String TAG = SqlData.class.getSimpleName();
// 定义一个表示无效ID的值，可能用于初始化或者标记不符合要求的ID情况
private static final int INVALID_ID = -99999;
// 定义查询数据时要获取的列名数组，用于指定从数据库获取哪些字段的数据
public static final String[] PROJECTION_DATA = new String[] {
DataColumns.ID, DataColumns.MIME_TYPE, DataColumns.CONTENT, DataColumns.DATA1,
DataColumns.DATA3
};
// 表示在查询结果游标中数据ID列的索引位置，方便从游标中获取对应的数据
public static final int DATA_ID_COLUMN = 0;
// 表示在查询结果游标中数据MIME类型列的索引位置
public static final int DATA_MIME_TYPE_COLUMN = 1;
// 表示在查询结果游标中数据内容列的索引位置
public static final int DATA_CONTENT_COLUMN = 2;
// 表示在查询结果游标中数据特定内容字段DATA1列的索引位置
public static final int DATA_CONTENT_DATA_1_COLUMN = 3;
// 表示在查询结果游标中数据特定内容字段DATA3列的索引位置
public static final int DATA_CONTENT_DATA_3_COLUMN = 4;
// 用于操作内容提供器，实现和数据库的数据交互，比如查询、插入、更新等操作
private ContentResolver mContentResolver;
// 标记是否是创建操作的标志位，true表示正在创建新数据，初始化为true
private boolean mIsCreate;
// 存储数据的ID，初始化为无效ID值
private long mDataId;
// 存储数据的MIME类型，初始化为默认的笔记类型（从DataConstants.NOTE获取）
private String mDataMimeType;
// 存储数据的内容，初始化为空字符串
private String mDataContent;
// 存储数据内容中特定的长整型数据（对应DATA1字段），初始化为0
private long mDataContentData1;
// 存储数据内容中特定的字符串数据（对应DATA3字段），初始化为空字符串
private String mDataContentData3;
// 用于存放要更新到数据库的数据值，类似一个键值对集合，方便批量更新操作
private ContentValues mDiffDataValues;
// 构造函数，传入上下文用于获取内容提供器，初始化相关成员变量，通常用于创建新数据的情况
public SqlData(Context context) {
mContentResolver = context.getContentResolver();
mIsCreate = true;
mDataId = INVALID_ID;
mDataMimeType = DataConstants.NOTE;
mDataContent = "";
mDataContentData1 = 0;
mDataContentData3 = "";
mDiffDataValues = new ContentValues();
}
// 另一个构造函数，传入上下文和游标，用于从已有的游标数据中加载信息初始化成员变量，通常用于读取现有数据的情况
public SqlData(Context context, Cursor c) {
mContentResolver = context.getContentResolver();
mIsCreate = false;
loadFromCursor(c);
mDiffDataValues = new ContentValues();
}
// 从游标中加载数据到成员变量的私有方法，按照定义好的列索引位置获取对应的数据赋值给成员变量
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);
}
// 根据传入的JSON对象设置相关数据成员变量，并将有变化的数据放入mDiffDataValues中，用于后续更新数据库操作
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;
}
// 根据当前成员变量的数据生成对应的JSON对象，若处于创建状态则记录错误日志并返回null
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;
}
// 将数据提交到数据库的方法，根据是否是创建操作执行不同的逻辑，创建则插入数据，否则根据条件更新数据
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的方法，外部可调用此方法获取当前对象关联的数据ID
public long getId() {
return mDataId;
}
}
Write Preview
Loading…
Cancel
Save