Utils.java

package com.annimon.java8streamexample;

import android.content.Context;
import android.util.Log;
import com.annimon.stream.Collectors;
import com.annimon.stream.Exceptional;
import com.annimon.stream.Stream;
import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;

public final class Utils {

    private static AdapterCollector sAdapterCollectorHolder;

    public static AdapterCollector collectAdapter(WordAdapter adapter) {
        if (sAdapterCollectorHolder == null) {
            sAdapterCollectorHolder = new AdapterCollector(adapter);
        }
        return sAdapterCollectorHolder;
    }

    public static List<Word> readWords(Context context) {
        return Exceptional.of(() -> {
            final List<String> lines = new ArrayList<>();
            try (final InputStream is = context.getAssets().open("words.txt");
                 final InputStreamReader isr = new InputStreamReader(is, "UTF-8");
                 final BufferedReader reader = new BufferedReader(isr)) {
                String line;
                while ( (line = reader.readLine()) != null ) {
                    lines.add(line);
                }
            }

            return Stream.of(lines)
                    .map(str -> str.split("\t"))
                    .filter(arr -> arr.length == 2)
                    .map(arr -> new Word(arr[0], arr[1]))
                    .collect(Collectors.toList());
        }).ifException(e -> Log.e("Java 8 Example", "Utils.readWords", e))
          .getOrElse(new ArrayList<>());
    }
}