The removeRange() method of ArrayList in Java is used to remove all elements within the specified range from an ArrayList object. It shifts any succeeding elements to the left. This call shortens the list by (toIndex-fromIndex) elements where toIndex is the ending index and fromIndex is the starting index within which all elements are to be removed. (If toIndex==fromIndex, this operation has no effect)
Syntax :
removeRange(int fromIndex, int toIndex)
Parameters :
There are two parameters :
1. fromIndex : starting index from which index elements are to be removed.
2. toIndex : within range[fromIndex-toIndex), all elements are removed.
The parameters are of int data-type.
Returns :
This method does not return any value. It only removes all the elements within the specified range.
Errors :
indexOutOfBoundsException: if fromIndex or toIndex is out of range (fromIndex = size() or toIndex > size() or toIndex < fromIndex)
Example 1 : Demonstrating the use of removeRange() method
// Java program to demonstrate the // working of removeRange() method import java.util.*; // extending the class to arryalist since removeRange() // is a protected method public class GFG extends ArrayList<Integer> { public static void main(String[] args) { // create an empty array list GFG arr = new GFG(); // use add() method to add values in the list arr.add(1); arr.add(2); arr.add(3); arr.add(12); arr.add(9); arr.add(13); // prints the list before removing System.out.println("The list before using removeRange:" + arr); // removing range of 1st 2 elements arr.removeRange(0, 2); System.out.println("The list after using removeRange:" + arr); } } |
Output:
The list before using removeRange:[1, 2, 3, 12, 9, 13] The list after using removeRange:[3, 12, 9, 13]
Example 2 : Program to demonstrate error
// Java program to demonstrate the error in // working of removeRange() method import java.util.*; // extending the class to arryalist since removeRange() // is a protected method public class GFG extends ArrayList<Integer> { public static void main(String[] args) { // create an empty array list GFG arr = new GFG(); // use add() method to add values in the list arr.add(1); arr.add(2); arr.add(3); arr.removeRange(1, 4); // error as 4 is out of range System.out.println("The list after using removeRange:" + arr); } } |
Output:
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException
at java.lang.System.arraycopy(Native Method)
at java.util.ArrayList.removeRange(ArrayList.java:638)
at GFG.main(GFG.java:25)
Note : removeRange(int fromIndex, int toIndex) method is protected method in ArrayList. A protected method is accessed in class, subclasses and in a package, but not public. Therefore we extend the class to arraylist.
Attention reader! Don’t stop learning now. Get hold of all the important Java Foundation and Collections concepts with the Fundamentals of Java and Java Collections Course at a student-friendly price and become industry ready.
