Java ArrayList isEmpty() Method
Java ArrayListThe isEmpty() method is used to determine whether the dynamic array is empty.
The syntax of the isEmpty() method is:
arraylist.isEmpty()
Note:arraylist is an object of the ArrayList class.
Parameter description:
- None
Return Value
Returns true if there are no elements in the array.
Returns false if there are elements in the array.
Example
Check whether the dynamic array is empty:
Example
import java.util.ArrayList;
class Main {
public static void main(String[] args){
// Create a dynamic array
ArrayList<String> sites = new ArrayList<>();
// Check whether the array contains elements
boolean result = sites.isEmpty(); // true
System.out.println("Is sites empty? " + result);
sites.add("Google");
sites.add("Example");
sites.add("Taobao");
System.out.println("Website list: " + sites);
// Check whether the array is empty
result = sites.isEmpty(); // false
System.out.println("Is sites empty? " + result);
}
}
class Main {
public static void main(String[] args){
// Create a dynamic array
ArrayList<String> sites = new ArrayList<>();
// Check whether the array contains elements
boolean result = sites.isEmpty(); // true
System.out.println("Is sites empty? " + result);
sites.add("Google");
sites.add("Example");
sites.add("Taobao");
System.out.println("Website list: " + sites);
// Check whether the array is empty
result = sites.isEmpty(); // false
System.out.println("Is sites empty? " + result);
}
}
Executing the above program produces the following output:
sites 是否为空? true 网站列表: [Google, Example, Taobao] sites 是否为空? false
In the example above, we created an array named sites, and the sites array uses the isEmpty() method to check whether the array contains elements.
Initially, the newly created array does not contain any elements. Therefore, isEmpty() returns true. Later, after we added some elements (Google, Example, etc.), the method returns false.
Other extensions