Sample usage of reduce operation in Java Stream API with one single parameter

StreamReduceFirstSample.java

    Car car1 = new Car("BMW", "Red", 35000d);
    Car car2 = new Car("Ford", "Yellow", 25000d);
    Car car3 = new Car("Toyota", "Red", 10000d);
    Car car4 = new Car("BMW", "Green", 35500d);

    List<Car> cars = Arrays.asList(car1, car2, car3, car4);

    //append all model into single line of string
    cars.stream()
        .map(c1 -> c1.getModel())
        .distinct()
        .reduce((s1, s2) -> s1 + "|" + s2)
        .ifPresent(System.out::println);
    //Output: BMW|Ford|Toyota