count popular words in pdf

App.java

import com.google.common.base.CharMatcher;

import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.Collections;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.stream.Collectors;

class Scratch {
    public static void main(String[] args) throws IOException {
        final LinkedHashMap<String, Long> sortedWords = read();
        write(sortedWords);
    }

    private static LinkedHashMap<String, Long> read() throws IOException {
        final var readPath = Paths.get(System.getProperty("user.home") + "/words");
        return Files.readAllLines(readPath)
                .stream()
                .map(str -> CharMatcher.is(',').or(CharMatcher.is('.')).or(CharMatcher.is(':')).trimTrailingFrom(str))
                .map(String::toLowerCase)
                .collect(Collectors.groupingBy(t -> t, Collectors.counting()))
                .entrySet()
                .stream()
                .sorted(Collections.reverseOrder(Map.Entry.comparingByValue()))
                .collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue, (e1, e2) -> e1, LinkedHashMap::new));
    }

    private static void write(LinkedHashMap<String, Long> sortedWords) throws IOException {
        final var writePath = Paths.get(System.getProperty("user.home") + "/hit");
        final var collect = sortedWords.entrySet().stream()
                .map(entrySet -> entrySet.getKey() + ":" + entrySet.getValue())
                .collect(Collectors.joining("\n"));

        Files.write(writePath, collect.getBytes(StandardCharsets.UTF_8));
    }

}

terminal.bash

pdftotext $HOME/my_book.pdf - | tr " " "\n" | sort | grep "^[A-Za-z]" > words