Question

试图运行代码，显示退出状态1 Main.java:9：错误：找不到符号 ArrayList结果= ArrayList merge（1、2）; ^ 符号：变量ArrayList 位置：班级主班

和类似的错误...

   import java.util.ArrayList;

   class Main {
              public static void main(String[] args) {
              String[] one = {"in","one","now"};
              String[] two = {"here","in","two"};
              ArrayList<String> result = ArrayList<String> merge(one,two);
              System.out.println(result);
   }

              private static ArrayList<String> merge(String[] words, String[] more){
              ArrayList<String> sentence = new ArrayList<String>();
              for(String w:words) {ArrayList.add(w);}
              for(String w:more) {ArrayList.add(w);}
              return sentence;
   }
 }

应该返回一个包含两个字符串数组内容的ArrayList，谢谢！：）

Answer 1

首先，ArrayList没有名为static的{{1}}方法。您想在add上调用它。并编程到sentence界面（您还需要导入List）；喜欢

java.util.List

此外，在private static List<String> merge(String[] words, String[] more) { List<String> sentence = new ArrayList<>(); for (String w : words) { sentence.add(w); } for (String w : more) { sentence.add(w); } return sentence; }中只需调用main，而无需添加更多类型信息。喜欢，

merge

上面的List<String> result = merge(one, two);也可以用merge编写，并与Arrays.asList(T...)相结合，例如

Collections.addAll

Answer 2

    import java.util.ArrayList;

    class Main {
       public static void main(String[] args) {
        String[] one = {"in","one","now"};
        String[] two = {"here","in","two"};
        ArrayList<String> result = merge(one,two);
        System.out.println(result);
       }

       private static ArrayList<String> merge(String[] words, String[] more){
        ArrayList<String> sentence = new ArrayList<String>();
        for(String w:words) {sentence.add(w);}
        for(String w:more) {sentence.add(w);}
        return sentence;
       }
     }

     Console:[in,one,now,here,in,two]

代码不会运行，说有问题，只说“找不到符号”

2 个答案: