在 java 中更有效地执行此任务以使用 CSV 插入 Room 数据库的方法

Question

我的 csv 文件有这样的内容

22,Boy,"Sri shandarachary, founder of adwaitha philosophy",Aadhishankar,Bengali

因为它在标记内有逗号，这就是为什么我得到错误的结果，得到的是名称的描述而不是名称本身

它在单个标记内有逗号，但被“”包围着

private List<BabyName> readData() {
    List<BabyName> babyNames = new ArrayList<>();
    InputStream is = getResources().openRawResource(R.raw.babynames);
    BufferedReader reader = new BufferedReader(
            new InputStreamReader(is, Charset.forName("UTF-8"))
    );
    String line = "";

    try {
        reader.readLine();
        String mGender, mMeaning, mName, mOrigin;
        while ((line = reader.readLine()) != null) {
            Log.d("MyActivity", "Line: " + line);

            String[] tokens = line.split(",");
            mGender = tokens[1];
            mMeaning = tokens[2];
            mName = tokens[3];
            mOrigin = tokens[4];

            BabyName babyName = new BabyName(mGender, mMeaning, mName, mOrigin);
            babyNames.add(babyName);
            Log.d(TAG, "Just created: " + mGender + mMeaning + mName + mOrigin);
        }

        database.babyDao().insertAll(babyNames);
    } catch (IOException e) {
        Log.wtf("MyActivity", "Error reading data file on line" + line, e);
        e.printStackTrace();
    }

    return babyNames;
}

这是我的 github 仓库，请随时提出 Pull 请求！！在这方面需要帮助

https://github.com/vivekpanchal/BabyApp

Answer 1

我想我找到了适合你的解决方案。

就是按索引遍历每个字符。

@Test
public void test() {
    String line = "22,Boy,\"Sri shandarachary, founder of adwaitha philosophy\",Aadhishankar,Bengali";
    List<String> result = new ArrayList<>(4);
    StringBuilder value = new StringBuilder();
    boolean inString = false;
    for (int index=0; index<line.length(); index++) {
        switch (line.charAt(index)) {
            case ',':
                if (inString) {
                    value.append(line.charAt(index));
                } else {
                    result.add(value.toString());
                    value = new StringBuilder();
                }
                break;
            case '\"':
                inString = !inString;
                break;
                default:
                    value.append(line.charAt(index));
        }
    }
    result.add(value.toString());
    for (String string : result) {
        System.out.println(string);
    }
}

System.out :

22
Boy
Sri shandarachary, founder of adwaitha philosophy
Aadhishankar
Bengali

Process finished with exit code 0

Answer 2

尝试Commons CSV Parser！

@Nullable private List<BabyName> readData() {
  InputStream in = null;
  BufferedReader reader = null

  try {
    List<BabyName> babyNames = new ArrayList<>();

    // open input stream to raw resource
    in =  = getResources().openRawResource(R.raw.babynames);

    // create a reader from it
    reader = new BufferedReader(new InputStreamReader(in));

    // parse as CSV
    CSVParser parser = CSVParser.DEFAULT.parse(reader);

    // get records
    for(CSVRecord record : parser){
      // Use the record.get(...) methods to get the column values
      // create BabyName from CSVRecord
      BabyName babyName = BabyName.fromCSVRecord(record);
      // Do whatever you want with the object
      // let's add it to the list of names
      babyNames.add(babyName);
    }

    return babyNames;
  } catch(Exception ex){
    Log.e(ex);
    return null;
  } finally {
    // always release the inputstream and reader
    Utils.closeSilently(reader);
    Utils.closeSilently(in);
  }
}

确保查看 https://commons.apache.org/proper/commons-csv/archives/1.5/apidocs/index.html

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在 java 中更有效地执行此任务以使用 CSV 插入 Room 数据库的方法

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