Last Updated : 11 Jul, 2025
The size() method of Java AbstractCollection is used to get the size of the Collection or the number of elements present in the Collection.
Syntax:
AbstractCollection.size()
Parameters: The method does not take any parameter.
Return Value: The method returns the size or the number of elements present in the collection.
Below programs illustrates the use of AbstractCollection.size() method:
Program 1:
// Java code to illustrate size()
import java.util.*;
import java.util.AbstractCollection;
public class AbstractCollectionDemo {
public static void main(String args[])
{
// Creating an empty Collection
AbstractCollection<String>
abs = new TreeSet<String>();
// Use add() method to add
// elements into the Collection
abs.add("Welcome");
abs.add("To");
abs.add("Geeks");
abs.add("4");
abs.add("Geeks");
abs.add("TreeSet");
// Displaying the Collection
System.out.println("Collection: " + abs);
// Displaying the size of the collection
System.out.println("The size of the Collection is: "
+ abs.size());
}
}
Collection: [4, Geeks, To, TreeSet, Welcome] The size of the Collection is: 5
Program 2:
// Java code to illustrate size()
import java.util.*;
import java.util.AbstractCollection;
public class AbstractCollectionDemo {
public static void main(String args[])
{
// Creating an empty Collection
AbstractCollection<String>
abs = new LinkedList<String>();
// Using add() method to add
// elements in the Collection
abs.add("Geeks");
abs.add("for");
abs.add("Geeks");
abs.add("10");
abs.add("20");
// Displaying the Collection
System.out.println("Collection:" + abs);
// Displaying the size of the Collection
System.out.println("The size of the Collection is: "
+ abs.size());
}
}
Collection:[Geeks, for, Geeks, 10, 20] The size of the Collection is: 5
RetroSearch is an open source project built by @garambo | Open a GitHub Issue
Search and Browse the WWW like it's 1997 | Search results from DuckDuckGo
HTML:
3.2
| Encoding:
UTF-8
| Version:
0.7.4