With this example we are going to demonstrate how to remove all elements from an ArrayList, that means clearing the arrayList. In short, to clear an ArrayList you should:
- Create a new ArrayList.
- Populate the arrayList with elements, using
add(E e)API method of ArrayList. - Invoke
clear()API method of ArrayList. The method removes all of the elements from this list.
We can get the size of the arrayList before and after clearing it. The size will be equal to zero after clearing it.
Let’s take a look at the code snippet that follows:
package com.javacodegeeks.snippets.core;
import java.util.ArrayList;
public class RemoveAllElementsArrayList {
public static void main(String[] args) {
// Create an ArrayList and populate it with elements
ArrayList arrayList = new ArrayList();
arrayList.add("element_1");
arrayList.add("element_2");
arrayList.add("element_3");
System.out.println("ArrayList size before removing elements : " + arrayList.size());
// ArrayList clear() operation removes all elements
arrayList.clear();
System.out.println("ArrayList size after removing elements : " + arrayList.size());
}
}
Output:
ArrayList size before removing elements : 3
ArrayList size after removing elements : 0
This was an example of how to remove all elements from an ArrayList in Java.
