The method filter(Predicate<? super Employee>) in the type Stream<Employee> is not applicable for the arguments ((<no type> e) -> {})

PAA :

How to set the values in Java 8 in filter ? I want to set emailId to null where firstName is Raj. How can I do that in Java8?

public class EmployeeDemo {
    public static void main(String[] args) {
        Employee e1 = new Employee("John", "Kerr", "[email protected]");
        Employee e2 = new Employee("Parag", "Rane", "[email protected]");
        Employee e3 = new Employee("Raj", "Kumar", "[email protected]");
        Employee e4 = new Employee("Nancy", "Parate", "[email protected]");

        List<Employee> employees = new ArrayList<>();
        employees.add(e1);
        employees.add(e2);
        employees.add(e3);
        employees.add(e4);

        employees.stream().filter(e -> {
            if(e.getFirstName().equals("Raj")) {
                e.setEmail(null);
            }
        }).
    }
}

ByeBye :

Filter method should return boolean and I think shouldn't have any side effects. In your case simple loop will do the job:

for(Employee employee: employees) {
    if(e.getFirstName().equals("Raj")) {
        e.setEmail(null);
    }
}

But if you really want to use stream:

employees.stream() //get stream
    .filter(e -> e.getFirstName().equals("Raj")) //filter entries with first name Raj
    .forEach(e -> e.setEmail(null)); //for each of them set email to null

or (if you want to do process the whole list and return changed with all entries:

employees.stream() //get stream
    .map(e -> {
        if(e.getFirstName().equals("Raj")) {
            e.setEmail(null);
        }
        return e;
    })
    .collect(Collectors.toList());