java - ArrayList 问题

Question

我正在尝试从句子中获取所有可能的单词对并将其存储到 ArrayList
其中MyClass.java

class MyClass{

private static ArrayList<String> wordList;
private static ArrayList<Integer> wordListCode;
private static int frequency;
private static int timeId;

public MyClass(ArrayList<String> words, int tid, int freq){
    wordList = new ArrayList<String>();
    wordListCode = new ArrayList<Integer>();

    if(words.get(0).hashCode()> words.get(1).hashCode()){
        wordList.add(words.get(0));    wordListCode.add(words.get(0).hashCode());
        wordList.add(words.get(1));    wordListCode.add(words.get(1).hashCode());
    }else{
        wordList.add(words.get(1));    wordListCode.add(words.get(1).hashCode());
        wordList.add(words.get(0));    wordListCode.add(words.get(0).hashCode());
    }
    frequency = freq;
    timeId = tid;
}}

我的问题是，当我尝试向 ArrayList 添加一个 MyClass 对象时，添加了一个节点，但替换了所有其他节点节点具有最后一个节点的值...

这是一些代码:

 ArrayList<MyClass> couples = new ArrayList<MyClass>();
    ArrayList<String[]> couplesList = new ArrayList<String[]>();
    couplesList = getWordCouplesList("demanding forensic technical comms systems");
    for(int o=0; o<couplesList.size(); o++){
        String word1, word2;
        if(couplesList.get(o)[0].hashCode()> couplesList.get(o)[1].hashCode() ){
            word1 = couplesList.get(o)[0];
            word2 = couplesList.get(o)[1];
        }else{
            word1 = couplesList.get(o)[1];
            word2 = couplesList.get(o)[0];
        }
        ArrayList<String> items = new ArrayList<String>(Arrays.asList(couplesList.get(o)));
        MyClass temp = new MyClass((ArrayList)items, 1, 1);
        couples.add( temp);
    }

    for(int i=0; i<couples.size(); i++){
        System.out.println((i+1)+"couple = "+couples.get(i).getWordList().get(0)+" , "+couples.get(i).getWordList().get(1));
    }  

<小时/>

这给出了输出:

1couple = comms , systems
2couple = comms , systems
3couple = comms , systems
4couple = comms , systems
5couple = comms , systems
6couple = comms , systems
7couple = comms , systems
8couple = comms , systems
9couple = comms , systems
10couple = comms , systems

Answer 1

class MyClass {

  private ArrayList<String> wordList;
  private ArrayList<Integer> wordListCode;
  private int frequency;
  private int timeId;
  ...
  .....
}

删除字段上的static修饰符。

这意味着您为该 MyClass 的每个对象使用相同的实例，这是您不想要的。您希望每个实例都有自己的列表和属性。

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