Java HashMap isEmpty()
[Java HashMap] Java HashMap
isEmpty() HashMap
isEmpty()
hashmap.isEmpty()
hashmap HashMap
HashMap / true false
isEmpty()
import java.util.HashMap;
class Main {
public static void main(String[] args) {
HashMap<Integer, String> sites = new HashMap<>();
// HashMap
boolean result = sites.isEmpty(); // true
System.out.println("? " + result);
// HashMap
sites.put(1, "Google");
sites.put(2, "Runoob");
sites.put(3, "Taobao");
System.out.println("HashMap: " + sites);
result = sites.isEmpty(); // false
System.out.println("? " + result);
}
}
class Main {
public static void main(String[] args) {
HashMap<Integer, String> sites = new HashMap<>();
// HashMap
boolean result = sites.isEmpty(); // true
System.out.println("? " + result);
// HashMap
sites.put(1, "Google");
sites.put(2, "Runoob");
sites.put(3, "Taobao");
System.out.println("HashMap: " + sites);
result = sites.isEmpty(); // false
System.out.println("? " + result);
}
}
? true
HashMap: {1=Google, 2=Runoob, 3=Taobao}
? false
sites HashMap isEmpty()
[Java HashMap] Java HashMap