Vector removeIf() method in Java (original) (raw)

Last Updated : 11 Jul, 2025

The removeIf() method of Vector removes all of those elements from Vector which satisfies the condition passed as a parameter to this method. This method returns true if some element are removed from the Vector. Java 8 has an important in-built functional interface which is Predicate. Predicate, or a condition checking function, which checks the given input for a given condition and returns a boolean result for the same indicating whether the condition was met or not.Syntax:

public boolean removeIf(Predicate<? super E> filter)

Parameter: This method takes a parameter filter which represents a predicate which returns true for elements to be removed.Returns: This method returns True if predicate returns true and some elements were removed.Exception: This method throws NullPointerException if the specified filter is null. Below programs illustrate removeIf() method of Vector:Example 1: To demonstrate removeIf() method on vector which contains a set of Numbers and only the numbers which are divisible by 2 will be removed.

Java `

// Java Program Demonstrate removeIf() // method of Vector

import java.util.*;

public class GFG { public static void main(String[] args) {

    // create an Vector which going to
    // contains a list of Numbers
    Vector<Integer> Numbers = new Vector<Integer>();

    // Add Number to list
    Numbers.add(22);
    Numbers.add(33);
    Numbers.add(55);
    Numbers.add(62);

    // apply removeIf() method
    // to remove numbers divisible by 2
    Numbers.removeIf(n -> (n % 2 == 0));

    System.out.println("All Numbers not divisible by 2 are:");

    // print list
    for (int i : Numbers) {
        System.out.println(i);
    }
}

}

`

Output:

All Numbers not divisible by 2 are: 33 55

Example 2: To demonstrate removeIf() method on Vector which contains set of Students Names and to remove all 4 char long name.

Java `

// Java Program Demonstrate removeIf() // method of Vector

import java.util.*;

public class GFG { public static void main(String[] args) {

    // create a Vector
    // containing a list of string values
    Vector<String> students = new Vector<String>();

    // Add Strings to list
    // each string represents student name
    students.add("Rama");
    students.add("Mohan");
    students.add("Sohan");
    students.add("Rabi");
    students.add("Shabbir");

    // apply removeIf() method
    // to remove names contains 4 chars
    students.removeIf(n -> (n.length() == 4));

    System.out.println("Students name do not contain 4 char are");

    // print list
    for (String str : students) {
        System.out.println(str);
    }
}

}

`

Output:

Students name do not contain 4 char are Mohan Sohan Shabbir

Example 3: To demonstrate NullpointerException in removeIf() method on Vector.

Java `

// Java Program Demonstrate removeIf() // method of Vector

import java.util.*;

public class GFG { public static void main(String[] args) {

    // create a Vector
    // containing a list of string values
    Vector<String> students = new Vector<String>();

    // Add Strings to list
    // each string represents student name
    students.add("Rama");
    students.add("Mohan");
    students.add("Sohan");
    students.add("Rabi");
    students.add("Shabbir");

    try {
        // apply removeIf() method with null filter
        students.removeIf(null);
    }
    catch (Exception e) {
        System.out.println("Exception: " + e);
    }
}

}

`

Output:

Exception: java.lang.NullPointerException

Reference: https://docs.oracle.com/javase/8/docs/api/java/util/Vector.html#removeIf-java.util.function.Predicate-