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我尝试四处搜索，但找不到明确的解决方案。

我想要做的是从 URL 下载一个始终更新的 XML 格式的新输入 SQL 文件，并将其保存在 /data/data/appprogram/files/ 文件夹中。文件下载完成，测试确认的文件通过DDMS文件浏览器下载到模拟器中。

接下来，我想打开这个文件以获取所有语句并将其解析到定义为 camera_database 的数据库中，该数据库位于 /data/data/appprogram/databases 中。这就是问题的开始。我无法超越这一点。

我尝试使用 inputstream 和 openfileinput 输入数据，但不工作。

下面是我使用的代码。请任何善良的灵魂提供建议..

public class Help_DatabaseHelperAdv extends SQLiteOpenHelper {

public static final String CAMERA_DATABASE_NAME = "camera_database";

protected Context camera_context;

public Help_DatabaseHelperAdv(Context context) {
    super(context, CAMERA_DATABASE_NAME, null, 1);
    this.camera_context = context;
}

@Override
public void onCreate(SQLiteDatabase cameradb) {
    String s;
    try {
        InputStream in = camera_context.getApplicationContext().openFileInput("/data/data/appprogram/files/alladvertlist.xml");


        DocumentBuilder builder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
        Document doc = builder.parse(in, null);
        NodeList statements = doc.getElementsByTagName("statement");
        for (int i=0; i<statements.getLength(); i++) {
            s = statements.item(i).getChildNodes().item(0).getNodeValue();
            cameradb.execSQL(s);
        }
    } catch (Throwable t) {
        Toast.makeText(camera_context, t.toString(), 50000).show();
    }
}

@Override
public void onUpgrade(SQLiteDatabase cameradb, int oldVersion, int newVersion) {
    cameradb.execSQL("DROP TABLE IF EXISTS alladvert");
    onCreate(cameradb);
}

}

感谢您的回复。希望补充，我做了一些测试以确保我的文件可以输入 /databases/ 文件夹。我在启动时将 alladvertlist.xml 放在 res/raw 文件夹中，使用

InputStream in = camera_context.getResources().openRawResource(R.raw.alladvertlist);

效果很好，我可以使用上述命令从 /databases/camera_database 检索 SQL 数据。

但是，当我将文件从 url 下载到特定文件夹 /data/data/appprogram/alladvertlist.xml 并使用 inputstream 将数据提取到 documentbuilder 时，它只是无法将文件解析为 /databases/camera_database。

下面是从 URL 下载文件并保存在工作正常的特定文件夹中的代码。供大家参考和使用，如果你觉得有用。

    /** Download a specified file from the web */
public void updateadvData(){

    final String file_url = this.getString(R.string.alladvertlisturl);
    /* Define and configure the progress dialog */
    final ProgressDialog myProgress = new ProgressDialog(this);
    myProgress.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
    myProgress.setMessage(this.getString(R.string.dialog_text));
    myProgress.setTitle(R.string.dialog_title);
    /* Show the progress dialog. */
    myProgress.show();

    /* Download our file */

    new Thread(new Runnable(){

        public void run(){
            try {

        //create the new connection
        URL url = new URL(file_url);
        HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();

        //set up some things on the connection
        urlConnection.setRequestMethod("GET");
        urlConnection.setDoOutput(true);

        //and connect!
        urlConnection.connect();




        File parentDirectory = new File("/data/data/appprogram/files");
        if(!parentDirectory.exists())
        {
            System.err.println("It seems like parent directory does not exist...");
            if(!parentDirectory.mkdirs())
            {
                 System.err.println("And we cannot create it...");
                 // we have to return, throw or something else
            }
        }



//           File file = new File(SDCardRoot,"filename.sqlite");
        File file = new File(parentDirectory, "alladvertlist.xml");
        if(file.exists())
        {
            System.err.println("Alladvertlist deleting...");
            file.delete();
        }

        file.createNewFile();


        //this will be used to write the downloaded data into the file we created
        FileOutputStream fileOutput = new FileOutputStream(file);


        //this will be used in reading the data from the internet
        InputStream inputStream = urlConnection.getInputStream();

        //this is the total size of the file
        int totalSize = urlConnection.getContentLength();
        myProgress.setMax(totalSize);
        //variable to store total downloaded bytes
        int downloadedSize = 0;

        //create a buffer...
        byte[] buffer = new byte[1024];
        int bufferLength = 0; //used to store a temporary size of the buffer
        int progress = 0;
        //now, read through the input buffer and write the contents to the file
        while ( (bufferLength = inputStream.read(buffer)) > 0 ) {
                //add the data in the buffer to the file in the file output stream (the file on the sd card
                fileOutput.write(buffer, 0, bufferLength);
                //add up the size so we know how much is downloaded
                downloadedSize += bufferLength;
                //Here we update the progress
                progress = downloadedSize;
                myProgress.setProgress(progress);
        } 

        //close the output stream when done
        fileOutput.close();
        myProgress.dismiss();
      //catch some possible errors...
    } catch (MalformedURLException e) {
            e.printStackTrace();
    } catch (IOException e) {
            e.printStackTrace();
    }
        }
    }).start(); 

}

当我对documentbuilder进行输入流时，我尝试搜索与字节或字符串有关，但似乎这并不是真正的原因。下面是可以从url下载的SQL文件的结构，去掉内容

<sql>
<statement> .... </statement>
</sql>

05-15 01:51:13.347: E/SQLiteLog(1391): (1) no such table: alladvert
05-15 01:51:13.347: D/AndroidRuntime(1391): Shutting down VM
05-15 01:51:13.347: W/dalvikvm(1391): threadid=1: thread exiting with uncaught exception (group=0x40a71930)
05-15 01:51:13.377: E/AndroidRuntime(1391): FATAL EXCEPTION: main
05-15 01:51:13.377: E/AndroidRuntime(1391): java.lang.RuntimeException: Unable to start activity     ComponentInfo{advertisebiz.gadgetscan/advertisebiz.gadgetscan.AdvPage02}: android.database.sqlite.SQLiteException: no such table: alladvert (code 1): , while compiling: SELECT _id, advcategory FROM alladvert WHERE advcategory = ?
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