Question

import java.util.*;
import java.lang.Iterable;

public class WordGroup {

    String words;

    public static void main(String[] args) {

        WordGroup plato = new WordGroup(
                "You can discover more about a person in an hour of play than in a year of conversation");
        WordGroup roosevelt = new WordGroup(
                "When you play play hard when you work dont play at all");
        String[] platoArray = plato.getWordArray();
        String[] rooseveltArray = roosevelt.getWordArray();
        plato.printArray(platoArray);
        roosevelt.printArray(rooseveltArray);
        System.out.println("____________________________________________________");
        HashSet<String> rooseveltWordSet = roosevelt.getWordSet(platoArray);
        roosevelt.printArray(rooseveltWordSet);

    }

    public WordGroup(String word) {
        words = word.toLowerCase();
    }

    protected String[] getWordArray() {
        String[] wordArray = words.split(" ");
        return wordArray;
    }

    protected HashSet<String> getWordSet(String[] groupedWords)

    {
        HashSet<String> wordSet = new HashSet<String>();
        for (String string : groupedWords) {
                wordSet.add(string);
        }

        String[] wordArray = getWordArray();
        for (String string : wordArray) {
                wordSet.add(string);

        }
        return wordSet;
    }

    protected void printArray(String[] array) {
        for (String string : array) {
            System.out.println(string);
        }
    }
    protected void printArray(HashSet<String> hashWords)
    {
        for(String hashset: hashWords)
        {
            System.out.println(hashset);
        }
    }
    protected void printArray(HashMap<String, Integer> printHashMap)
    {
        for(String string: printHashMap)
        {
            System.out.println(string);
        }
    }
    protected HashMap<String, Integer> getWordCounts()
    {

        String[] wordArray = getWordArray();

        HashMap<String, Integer> wordCounts = new HashMap<String, Integer>();
        for(String string: wordArray)
        {
            int one = 1;
            wordCounts.put(string, +one);

        }

        return null;

    }
}

我试图让getWordCounts（）创建一个hashmap，其中包含两个字符串中使用的单词，并记住单词和单词使用的次数。 printArray（HashMap printHashMap）用于遍历在getWordCounts（）中创建的HashMap并打印出数据。

Answer 1

将getWordCounts方法更改为：

protected Map<String, Integer> getWordCounts()
{
String[] wordArray = getWordArray();
Map<String, Integer> wordCounts = new HashMap<String, Integer>();
List<String> list = Arrays.asList(wordArray);
Set<String> set = new HashSet<String>(list);
for (String str : set) {
    wordCounts.put(str, Collections.frequency(list, str));
}
return wordCounts;
}

要打印地图元素，请将printArray方法更改为：

protected void printArray(HashMap<String, Integer> printHashMap){
Iterator<Entry<String, Integer>> iter = printHashMap.entrySet().iterator();
    while (iter.hasNext()) {
        Entry<String, Integer> next = iter.next();
        Integer value = next.getValue();
        System.out.println("key = " + next.getKey());
        System.out.println("value = " + value);
    }
}

Answer 2

我已将代码更改为：

import java.util.*;
import java.lang.Iterable;

public class Main {

    String words;

    public static void main(String[] args) {

        Main plato = new Main(
                "You can discover more about a person in an hour of play than in a year of conversation");
        Main roosevelt = new Main(
                "When you play play hard when you work dont play at all");
        String[] platoArray = plato.getWordArray();
        String[] rooseveltArray = roosevelt.getWordArray();
        plato.printArray(platoArray);
        roosevelt.printArray(rooseveltArray);
        System.out.println("____________________________________________________");
        HashSet<String> rooseveltWordSet = roosevelt.getWordSet(platoArray);
        roosevelt.printArray(rooseveltWordSet);
        System.out.println("____________________________________________________");
        roosevelt.printArray(roosevelt.getWordCounts());
        System.out.println("____________________________________________________");

    }

    public Main(String word) {
        words = word.toLowerCase();
    }

    protected String[] getWordArray() {
        String[] wordArray = words.split(" ");
        return wordArray;
    }

    protected HashSet<String> getWordSet(String[] groupedWords)

    {
        HashSet<String> wordSet = new HashSet<String>();
        for (String string : groupedWords) {
                wordSet.add(string);
        }

        String[] wordArray = getWordArray();
        for (String string : wordArray) {
                wordSet.add(string);

        }
        return wordSet;
    }

    protected void printArray(String[] array) {
        for (String string : array) {
            System.out.println(string);
        }
    }
    protected void printArray(HashSet<String> hashWords)
    {
        for(String hashset: hashWords)
        {
            System.out.println(hashset);
        }
    }
    /*Changed*/
    protected void printArray(HashMap<String, Integer> printHashMap)
    {
        for(String string: printHashMap.keySet())
        {
            System.out.println(string + ":" + printHashMap.get(string) );
        }
    }

    /*changed*/
    protected HashMap<String, Integer> getWordCounts()
    {

        String[] wordArray = getWordArray();

        HashMap<String, Integer> wordCounts = new HashMap<String, Integer>();
        for(String string: wordArray)
        {
            if(wordCounts.containsKey(string)){
                wordCounts.put(string, wordCounts.get(string) + 1);
            }else{
                wordCounts.put(string, 1);
            }

        }

        return wordCounts;

    }
}

创建和打印HashMap <string，integer =“”> </string，>

2 个答案: