Main.java Source code

Java tutorial

Introduction

Here is the source code for Main.java

Source

import java.util.Arrays;
import java.util.List;
import java.util.Optional;

public class Main {

    public static void main(String[] args) throws Exception {
        List<Dish> menu = Arrays.asList(new Dish("pork", false, 800, Dish.Type.MEAT),
                new Dish("beef", false, 700, Dish.Type.MEAT), new Dish("chicken", false, 400, Dish.Type.MEAT),
                new Dish("rice", true, 350, Dish.Type.OTHER), new Dish("pizza", true, 550, Dish.Type.OTHER),
                new Dish("prawns", false, 400, Dish.Type.FISH), new Dish("salmon", false, 450, Dish.Type.FISH));
        // Filtering with predicate
        Optional<Dish> vegetarianMenu = menu.stream().filter(Dish::isVegetarian).findAny();

        vegetarianMenu.ifPresent(d -> System.out.println(d.getName()));

    }

}

class Dish {

    private final String name;
    private final boolean vegetarian;
    private final int calories;
    private final Type type;

    public Dish(String name, boolean vegetarian, int calories, Type type) {
        this.name = name;
        this.vegetarian = vegetarian;
        this.calories = calories;
        this.type = type;
    }

    public String getName() {
        return name;
    }

    public boolean isVegetarian() {
        return vegetarian;
    }

    public int getCalories() {
        return calories;
    }

    public Type getType() {
        return type;
    }

    public enum Type {
        MEAT, FISH, OTHER
    }

    @Override
    public String toString() {
        return name;
    }

}