java - 将数据从 CSV 保存到 Realm

Question

我一直在创建一个字典应用程序，我将所有单词保存在 .csv 文件中
当应用程序第一次运行时，此方法应将所有单词保存到 realm db 但只保存少数。

Task java.util.concurrent.FutureTask@286858df rejected from io.realm.internal.async.RealmThreadPoolExecutor@273caff5[Running, pool size = 13, active threads = 13, queued tasks = 100, completed tasks = 1]

realm = Realm.getDefaultInstance();



    //adding to db satrt
    if (!(realm.isEmpty())) {
        Log.v("DB","already there!!");
    } else {
        Log.v("DB","Not Found!!");
        String csvFile = "longevity.csv";
        BufferedReader br = null;
        String line = "";
        String cvsSplitBy = ",";

        try {

            br = new BufferedReader(new InputStreamReader(getAssets().open(csvFile)));
            while ((line = br.readLine()) != null) {

                // use comma as separator
                final String[] oneWord= line.split(cvsSplitBy);



                realm.executeTransactionAsync(new Realm.Transaction() {
                    @Override
                    public void execute(Realm bgRealm) {
                        Word user = bgRealm.createObject(Word.class);
                        user.setWord(oneWord[1]);
                        user.setMeaning(oneWord[2]);
                        user.setSynonyms(oneWord[3]);
                    }
                }, new Realm.Transaction.OnSuccess() {
                    @Override
                    public void onSuccess() {
                        Log.v("TAGGED","SAVED");
                    }
                }, new Realm.Transaction.OnError() {
                    @Override
                    public void onError(Throwable error) {
                        Log.v("TAGGED","FAILED");
                    }
                });
            }

        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (br != null) {
                try {
                    br.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }

    }

有没有更好的方法来使用 android 发送预填充的 Relam 数据库， 当应用程序第一次运行时，我有 146800 个单词要保存到数据库中，这种方法只保存了几个单词，然后在上面显示错误!

Answer 1

使用 1 个交易而不是 146800 个交易。还可以考虑使用 1 个实例来保存您的 Realm 对象，而不是创建 146800 个对象。

    realm.executeTransactionAsync(new Realm.Transaction() {
        @Override
        public void execute(Realm bgRealm) {
            String csvFile = "longevity.csv";
            BufferedReader br = null;
            String line = "";
            String cvsSplitBy = ",";
            try {
                br = new BufferedReader(new InputStreamReader(getAssets().open(csvFile)));
                Word user = new Word();
                while((line = br.readLine()) != null) {
                    // use comma as separator
                    final String[] oneWord = line.split(cvsSplitBy);
                    user.setWord(oneWord[1]);
                    user.setMeaning(oneWord[2]);
                    user.setSynonyms(oneWord[3]);
                    bgRealm.insert(user);
                }
            } catch(Throwable e) {
                e.printStackTrace();
                throw e;
            } finally {
                if(br != null) {
                    try {
                        br.close();
                    } catch(IOException e) {
                        e.printStackTrace();
                    }
                }
            }
        }
    }, new Realm.Transaction.OnSuccess() {
        @Override
        public void onSuccess() {
            Log.v("TAGGED", "SAVED");
        }
    }, new Realm.Transaction.OnError() {
        @Override
        public void onError(Throwable error) {
            Log.v("TAGGED", "FAILED");
        }
    });

编辑:您应该考虑使用 CSV parser library ，因为 String.split() 是内存密集型的。

代替

while ((line = br.readLine()) != null) {

考虑一下

final CSVParser parser = new CSVParser(reader, CSVFormat.EXCEL.withHeader());
for (final CSVRecord record : parser) {
    ...