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java无法连接到数据库(安卓上的SQLite)

我用java这样做了db:

public static void main(String[] args) throws Exception {
      String CITIES[] = city.split(",");
      Class.forName("org.sqlite.JDBC");
        Connection conn = DriverManager.getConnection("jdbc:sqlite:test.db");

       String V[][] = {COUNTRIES,CITIES,occupations}; 
       String []TypeNames = {"country","city","occupation"};
        Statement stat = conn.createStatement();
    stat.executeUpdate("drop table if exists "+TABLE_NAME+";");
    //stat.executeUpdate("create table "+TABLE_NAME+" (name, occupation);");
    stat.executeUpdate("create table "+TABLE_NAME+" ("+VALUE+","+TYPE+","+LETTER+");");
    PreparedStatement prep = conn.prepareStatement(
      "insert into "+TABLE_NAME+" values (?, ?,?);");

    //private void insertToTalble();
    for(int j = 0 ;j < V.length; j++)
        for (int i = 0 ;i < V[j].length ; i++)
        {
        Character c = V[j][i].charAt(0);
        prep.setString(1, V[j][i]+"\n");
        prep.setString(2, TypeNames[j]);
        prep.setString(3, c.toString());

        prep.addBatch();
        }

    conn.setAutoCommit(false);
    prep.executeBatch();
    conn.setAutoCommit(true);

    rs.close();
    conn.close();
  }
}

当我使用sqllight数据浏览器打开它时,它可以正常工作,但在我的安卓项目databases/test1中将它添加到新的目录中之后。分贝

我使用它有问题

我与数据库一起工作的安卓类是:

     private static final String DB_PATH = "/data/data/com.countryCityGame/databases/test.db";
    private static final String DATABASE_NAME = "test1.db";
    private static final int DATABASE_VERSION = 1;
    private static final String TABLE_NAME = "GameTable";
    private static final String VALUE = "value";
    private static final String TYPE = "type";
    private static final String LETTER = "letter";


    public countryCityGameLogic(EditText[] myEditTextArr , Context context){

        this.context = context;
        openHelper = new OpenHelper(context);
        gameList = new CharSequence [myEditTextArr.length];
        for (int i = 0 ; i < myEditTextArr.length; i++){
            gameList[i] = myEditTextArr[i].getText();
        }
        this.db = openHelper.getWritableDatabase();

        try{
            String myPath = DB_PATH ;
            SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READONLY);

        }catch(SQLiteException e){

            //database does't exist yet.
            //insertValus(COUNTRIES,0);

        }
        //insertValus(COUNTRIES,0);
    }
    public void setGameVar(EditText[] myEditTextArr) {
        for (int i = 0 ; i < myEditTextArr.length ;i++)
        gameList[i] = myEditTextArr[i].getText();
    }
    private void insertValus(String []typeInserted , int num) {
        ContentValues initialValues = new ContentValues();
          for (int i = 0 ; i < typeInserted.length ; i++){
              Character tmp = (Character)typeInserted[i].charAt(0);
              initialValues.put(VALUE, typeInserted[i]);
              initialValues.put(TYPE, TYPESNAMES[num]);
              initialValues.put(LETTER,tmp.toString(tmp));

          db.insert(TABLE_NAME, null, initialValues);
          }
    }



    private static class OpenHelper extends SQLiteOpenHelper {

          OpenHelper(Context context) {
             super(context, DATABASE_NAME, null, DATABASE_VERSION);
          }

          @Override
          public void onCreate(SQLiteDatabase db) {
             db.execSQL("CREATE TABLE IF NOT EXISTS " + TABLE_NAME + " ( "+ VALUE +" TEXT,"+ TYPE +" TEXT, "+ LETTER + " TEXT)");
          }

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


    public boolean existInDataBase() {
        boolean returnval = true;


        String s = asUpperCaseFirstChar(gameList[0].toString());
        Cursor cursor = db.query(TABLE_NAME, new String[] {VALUE}
        ,VALUE+" like " + "'%" + s +"%'", null, null, null, null);

        if ( cursor.moveToFirst() == false)
            returnval = false;

        return returnval;
    }

existInDataBase()函数中的游标中没有任何信息 更具体地说,对于游标,我总是得到false。moveToFirst()即使我的查询只是选择,没有任何东西

有人能: 1.告诉我他怎么想 2.我如何调试并查看数据库中有什么(我调试但我看不到任何奇怪的东西,如果我说“你没有数据库”的话)

注意“当我第一次构建应用程序时,应用程序就是构建db的那个人,正如你在

 private void insertValus(String []typeInserted , int num);

我的问题似乎是清单文件:

当一个人把一个db文件导入他的安卓项目时,他应该怎么做?请分步解释我该怎么做谢谢你


共 (0) 个答案