import java.io.*;
        import java.util.*;

public class WordCount {
    private static final File ROOT_File =new File("D:\\桌面");
    private static int count = 0;
    private static Map<String,Integer> wordCount = new HashMap<>();

    public static void main(String [] args) throws Exception{
        String intputFileName =  args[0];
        String outputFileName = args[1];
        File inputFile = new File(ROOT_File,intputFileName);
        File outputFile = new File(ROOT_File,outputFileName);

        // 判断是否存在:
        if(inputFile.exists()){
            doCheck(inputFile);
        }else{
            throw new RuntimeException("error");
        }
        PrintStream stream = new PrintStream(new FileOutputStream(outputFile));
        System.setOut(stream);
        show();
        System.out.println("单词数:"+obtainTotalWords());
        System.out.println("行数:"+count);
        System.out.println("字符数:"+(inputFile.length()));


    }

    public  static void doCheck(File inputFile) throws Exception{
        BufferedReader br = new BufferedReader(new InputStreamReader(new FileInputStream(inputFile)));
        String line = null;
        while(null!=(line=br.readLine())){
            incrLine();
            // 分析每一行。
            analysis(line);
        }
    }

    public static void show(){
        Set<Map.Entry<String, Integer>> entries = wordCount.entrySet();
        // 排序
        ArrayList<String> words = new ArrayList<>();
        for (Map.Entry<String, Integer> entry : entries) {
            words.add(entry.getValue()+"#"+entry.getKey());
        }

        // 排序
        Collections.sort(words);
        words.forEach(obj->{
            String[] split = obj.split("#");
            String str = split[1]+": "+split[0];
            System.out.println(str);
        });
    }

    public static void incrLine(){
        // 行数加1
        count++;
    }

    //总单词数
    public static long obtainTotalWords(){
        long sum = 0;
        Set<Map.Entry<String, Integer>> entries = wordCount.entrySet();
        for (Map.Entry<String, Integer> entry : entries) {
            sum+=entry.getValue();
        }
        return sum;
    }

    // 得到每一个单词以及次数, 并且记录到Map集合中
    public static void analysis(String line){
        String [] words = line.split(" ");
        for(int i=0;i<words.length;i++){
            String word = words[i].trim();
            word = word.toLowerCase();
            word = word.contains(",")||word.contains(".")?word.substring(0,word.length()-1):word;
            if(word.length()>=4&&isWord(word.substring(0,4))){
                if(wordCount.containsKey(word)){
                    Integer count = wordCount.get(word);
                    count++;
                    wordCount.put(word,count);
                }else{
                    wordCount.put(word,1);
                }
            }
        }
    }

    public static boolean isWord(String word){
        for(int i=0;i<word.length();i++){
            if(word.charAt(i)>=97 && word.charAt(i)<=122){
                continue;
            }else{
                return false;
            }
        }
        return true;
    }
}