List remove(Object obj) method in Java with Examples
The remove(Object obj) method of List interface in Java is used to remove the first occurrence of the specified element obj from this List if it is present in the List.
Example:
// Java Program Illustrate List
// remove(Element) Method
import java.util.*;
class GFG
{
public static void main (String[] args) {
List<Integer> l=new ArrayList<Integer>();
l.add(1);
l.add(2);
l.add(3);
// Initial list
System.out.println("Initial List: " + l);
Integer t = new Integer(3);
// Remove element
l.remove(t);
// Final list
System.out.println("Final List: " + l);
}
}
Output
Initial List: [1, 2, 3] Final List: [1, 2]
Syntax of Method
boolean remove(Object obj)
Parameter: It accepts a single parameter obj of List type which represents the element to be removed from the given List.
Return Value: It returns a boolean value True after removing the first occurrence of the specified element from the List and otherwise if the element is not present in the List then this method will return False.
Examples of List remove(Object obj)
Below program illustrate the remove(Object obj) method of List in Java.
Program 1:
// Program to illustrate the
// remove(int index) method
import java.util.*;
public class GFG
{
public static void main(String[] args)
{
// Declare an empty List of size 5
List<Double> l = new ArrayList<Double>(5);
// Add elements to the list
l.add(5.0);
l.add(10.5);
l.add(15.1);
l.add(20.6);
l.add(25.2);
// Element needed to be removed
double obj = 15.1;
// Initial list
System.out.println("Initial List: " + l);
// remove element
l.remove(obj);
// Final list
System.out.println("Final List: " + l);
}
}
Output
Initial List: [5.0, 10.5, 15.1, 20.6, 25.2] Final List: [5.0, 10.5, 20.6, 25.2]
Program 2:
// Java Program to illustrate the
// remove(int index) method
import java.util.*;
public class GFG
{
public static void main(String[] args)
{
// Declare an empty List of size 5
List<String> l = new ArrayList<String>(5);
// Add elements to the list
l.add("Welcome");
l.add("to");
l.add("Geeks");
l.add("for");
l.add("Geeks");
// Element to be removed
String obj = "for";
// Initial list
System.out.println("Initial List: " + l);
// remove element
l.remove(obj);
// Final list
System.out.println("Final List: " + l);
}
}
Output
Initial List: [Welcome, to, Geeks, for, Geeks] Final List: [Welcome, to, Geeks, Geeks]
Note: Be careful while using a List of integers as while passing an integer element to the remove method, the list will treat the method as remove(int index). It will consider the element as index and not actual element.
Reference: https://docs.oracle.com/javase/8/docs/api/java/util/List.html#remove-java.lang.Object-