ArrayList removeIf() method in Java
The removeIf() method of ArrayList is used to remove all of the elements of this ArrayList that satisfies a given predicate filter which is passed as a parameter to the method.
Errors or runtime exceptions are thrown during iteration or by the predicate are pass to the caller. This method returns True, if we are able to remove some element.
Java 8 has an important in-built functional interface which is Predicate. Predicate, or a condition checking function, check the given input for a given condition and returns a boolean result for the same indicating whether the condition was met or not.
public boolean removeIf(Predicate 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 we are able to remove elements.
Exception: This method throws NullPointerException if the specified filter is null.
Below programs illustrate removeIf() method of ArrayList:
Program 1: Program to demonstrate removeIf() method on ArrayList which contains a set of Numbers and only the numbers which are divisible by 3 will be removed.
Program 2: Program to demonstrate removeIf() method on ArrayList which contains set of Students Names and names starting with “S” will be removed.
Students name Does not start with S Ram Mohan Rabi