On IntelliJ IDEA. Unable to add String to ArrayList<String>. Error: "Cannot resolve symbol 'add' "

Question

static List<String> commands = new ArrayList<>(asList("Hello", "Goodbye"));
commands.add("Hi!");

编译器错误：

错误：(37, 17) java：<identifier> 预期

错误:(37, 18) java: 非法开始类型

这些位置在 .add() 的左括号前后；

Answer 1

像这样：

class MyClass {

static List<String> commands = new ArrayList<>(asList("Hello", "Goodbye"));
commands.add("Hi!");

}

是非法的。您不能在 class 定义中调用方法。

要使其工作，请使用静态块：

 class MyClass {

    static List<String> commands = new ArrayList<>(asList("Hello", "Goodbye"));
      static {
         commands.add("Hi!");
      }
    }

On IntelliJ IDEA. Unable to add String to ArrayList<String>. Error: "Cannot resolve symbol 'add' "

On IntelliJ IDEA. Unable to add String to ArrayList<String>. Error: "Cannot resolve symbol 'add' "

java

symbols

intellij-idea