在 For-Loop 中重新启动 ArrayList

Question

我会保持简单：我有一个名称的 ArrayList，我必须删除包含特定字母的某些单词，但是我无法重新启动 for 循环。这是我得到的：

public static void someRandomFunction(){

    List<String> arrList = new ArrayList<>(Arrays.asList("Hello",

                                                     "Everyone",

                                                     "I'm",

                                                     "Struggling",

                                                     "In",

                                                     "Computer",

                                                     "Science"));

    System.out.println("Start of List: " + wordList + "\n"); 

    System.out.println("\nDrop: \"a\""); 

    someRandomFunction(wordList, "a");

    System.out.println("wordList is now: " + wordList);

}

public static List<String> removeIfContains(List<String> strList, String removeIf){

    List<String> tempList = new ArrayList<>(strList); // creating a copy

    for(int i = 0; i < tempList.size(); i++){

        if(tempList.get(i).contains(removeIf))

            tempList.remove(i);

    }

//Return will not work because of incompatible types.

}

编译后的代码应该是什么的一个例子：

ArrayList [你好，大家，我，我，挣扎，在，计算机，科学]

删除以“A”开头的单词：

新的 ArrayList [你好，大家，我，正在奋斗，在，计算机，科学]

删除以“I”开头的单词：

新的 ArrayList [你好，大家，上午，奋斗，计算机，科学]

我的代码的问题在于，当它开始读取需要删除的新单词时，它不会将单词列表返回到之前的状态。

Answer 1

如果您只想删除ArrayList以某个字母开头的每个元素，您可以使用以下removeIf()方法：删除此集合中满足给定谓词的所有元素。wrodList.removeIf(e&nbsp;->&nbsp;e.contains(thisLetter));（需要 Java 8+）听起来您希望在每次删除元素后重置列表。为此，您可以创建一个副本ArrayList进行检查，然后在每次之后将其设置回原始副本：List<String>&nbsp;copy&nbsp;=&nbsp;new&nbsp;ArrayList<>(wordList);&nbsp;//Creates&nbsp;a&nbsp;copy&nbsp;of&nbsp;wordList

Answer 2

我相信这就是你正在寻找的。我不确定你是想要一个实例还是静态方法。我相信您的问题是您没有创建副本。我记下了我在哪里创建副本。祝你在 CS 中好运......我们都曾一度陷入困境。public static void someRandomFunction(){&nbsp; &nbsp; List<String> arrList = new ArrayList<>(Arrays.asList("Hello",&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;"Everyone",&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;"I'm",&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;"Struggling",&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;"In",&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;"Computer",&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;"Science"));&nbsp; &nbsp; System.out.println(removeIfContains(arrList, "H")); // calling the function and passing the list and what&nbsp; &nbsp; System.out.println(removeIfContains(arrList, "I")); // I want to remove from the list}public static List<String> removeIfContains(List<String> strList, String removeIf){&nbsp; &nbsp; List<String> tempList = new ArrayList<>(strList); // creating a copy&nbsp; &nbsp; for(int i = 0; i < tempList.size(); i++){&nbsp; &nbsp; &nbsp; &nbsp; if(tempList.get(i).contains(removeIf))&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; tempList.remove(i);&nbsp; &nbsp; }&nbsp; &nbsp; return tempList; // returning the copy}