java - 如何向由 arraylist 组成的 main 方法抛出异常？

Question

/创建一个方法callMethod，其中显示数组列表中的所有国家，如果超过5个国家，该方法将向main()方法抛出异常/

导入java.util.Arrays;

导入java.util.List;

导入java.util.ListIterator;

公共(public)类别国家{

static List<String> country = Arrays.asList("Singapore", "America", "France","Japan","China","UK","Indonesia","India");

public static void main(String[] args) {

    ListIterator<String> myListIterator = country.listIterator();
    while (myListIterator.hasNext()) {

        System.out.print(myListIterator.next() + " ");


    }
    System.out.println();

    Countries countries = new Countries();
    countries.callMethod();
}

public void callMethod() {
    try {
       System.out.println(country.get(6));
    } catch (ArrayIndexOutOfBoundsException e) {
        System.out.println("Maximum countries is 5");
    }
}

}

Answer 1

用类似的东西定义你的方法

public void callMethod() {
        if (null!=country && country.size() > 5) {
            throw new RuntimeException("Maximum countries allowed are 5");
        }
    }

您可以通过使用 try{...}catch(){} 包装 callMethod 调用来捕获错误

try {
      countries.callMethod();
    } catch (RuntimeException rex) {
      rex.printStackTrace();
    }