从其他类访问HashMap

Question

我的班级有一个名为DataStorage的哈希图：

HashMap<String, Integer> people = new HashMap<String, Integer>();

people.put("bob", 2);
people.put("susan", 5);

如何在另一个类中访问此HashMap中的数据？

Answer 1

将HashMap创建为实例变量，并提供一种将其访问类API的方法：

public class DataStorage {
    private HashMap<String, Integer> people = new HashMap<String, Integer>();

    public HashMap<String, Integer> getPeopleMap() {
         return people;
    }
}

public class AnotherClass {
      DataStorage x = new DataStorage();

      private void someMethod() {
           HashMap<String, Integer> people = x.getPeopleMap();
           //work with your map here...
      }  
}