The toString() method of JavaAbstractClass is used to return a string representation of the elements of the Collection.
The String representation comprises a list representation of the elements of the Collection in the order they are picked by the iterator closed in square brackets[].This method is used mainly to display collections other than String type(for instance: Object, Integer)in a String Representation.
Syntax:
Object.toString();
Parameter The method does not take any parameters.
Return This method returns a string representation of the collection.
Below examples illustrate the toString() method:
Example 1:
// Java program to demonstrate // Abstract Collection toString() method import java.util.*; public class collection { public static void main(String args[]) { // Creating an Empty AbstractCollection AbstractCollection<String> abs = new PriorityQueue<String>(); // Use add() method // to add elements to the Collection abs.add( "Welcome" ); abs.add( "To" ); abs.add( "Geeks" ); abs.add( "For" ); abs.add( "Geeks" ); // Using toString() method System.out.println(abs.toString()); } } |
[For, Geeks, To, Welcome, Geeks]
Example 2:
// Java program to demonstrate // Abstract Collection toString() method import java.util.*; public class collection { public static void main(String args[]) { // Creating an Empty AbstractCollection AbstractCollection<Integer> abs = new PriorityQueue<Integer>(); // Use add() method // to add elements to the Collection abs.add( 10 ); abs.add( 20 ); abs.add( 30 ); abs.add( 40 ); // Using toString() method System.out.println(abs.toString()); } } |
[10, 20, 30, 40]
Reference: https://docs.oracle.com/javase/9/docs/api/java/util/AbstractCollection.html#toString–