创建大量数据的Android应用数据库 [英] Creating android app Database with big amount of data

问题描述

我的应用程序的数据库需要填充大量的数据
所以在 onCreate（），它不仅仅是一些创建表sql
指令，有很多插入。我选择的解决方案是
将所有这些说明存储在位于res / raw的sql文件中，并且
加载了 Resources.openRawResource（id）。

The database of my application need to be filled with a lot of data, so during onCreate(), it's not only some create table sql instructions, there is a lot of inserts. The solution I chose is to store all this instructions in a sql file located in res/raw and which is loaded with Resources.openRawResource(id).

它工作得很好，但我面对编码问题，我有一些突出的
caharacters在sql文件，这在我的应用程序中显得不好。这个
我的代码这样做：

It works well but I face to encoding issue, I have some accentuated caharacters in the sql file which appears bad in my application. This my code to do this:

public String getFileContent(Resources resources, int rawId) throws
IOException
  {
    InputStream is = resources.openRawResource(rawId);
    int size = is.available();
    // Read the entire asset into a local byte buffer.
    byte[] buffer = new byte[size];
    is.read(buffer);
    is.close();
    // Convert the buffer into a string.
    return new String(buffer);
  }

public void onCreate(SQLiteDatabase db) {
   try {
        // get file content
        String sqlCode = getFileContent(mCtx.getResources(), R.raw.db_create);
        // execute code
        for (String sqlStatements : sqlCode.split(";"))
        {
            db.execSQL(sqlStatements);
        }

        Log.v("Creating database done.");
        } catch (IOException e) {
            // Should never happen!
            Log.e("Error reading sql file " + e.getMessage(), e);
            throw new RuntimeException(e);
        } catch (SQLException e) {
            Log.e("Error executing sql code " + e.getMessage(), e);
            throw new RuntimeException(e);
        }

我发现避免这种情况的解决方案是加载sql指令
从一个巨大的 static final String 而不是一个文件，所有
加强字符出现得很好。

The solution I found to avoid this is to load the sql instructions from a huge static final String instead of a file, and all accentuated characters appear well.

但是没有比所有sql指令大的
static final String 属性更加优雅的方式来加载sql指令吗？

But isn't there a more elegant way to load sql instructions than a big static final String attribute with all sql instructions?

推荐答案

我认为你的问题在这一行：

I think your problem is in this line:

return new String(buffer);

您正在将字节数组转换为 java.lang。 String ，但是你不是告诉Java / Android使用的编码。因此，由于使用了错误的编码，因此重音字符的字节未正确转换。

You're converting the array of bytes in to a java.lang.String but you're not telling Java/Android the encoding to use. So the bytes for your accented characters aren't being converted correctly as the wrong encoding is being used.

如果使用 String（byte []， encoding>） 构造函数，您可以指定文件的编码，并且字符将被正确转换。

If you use the String(byte[],<encoding>) constructor you can specify the encoding your file has and your characters will be converted correctly.

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