Consider a list of movies. Write code to create a new ArrayList of all the movies, then use method removeIf of ArrayList to remove all movies produced before 1960. First, use an anonymous class as the explicit argument to removeIf. Once this work, replace the anonymous class with a lambda expression written as a block of statements, and with type parameter. Finally, transform your lambda expression once again so that it is defined as an expression, has no type parameter or parentheses.
Add a method isOld(): boolean to class Movie, and use a reference to this method in the code of Exercise 1.
Use the method Iterable.forEach to print the description of all movies to System.out. First, use an anonymous class. Then, write a lamda expression. Then, write a static method print(Movie): void that encapsulates the printing behavior, and use this method in the lambda expression. Then, replace the lambda expression with a method reference. Finally, notice that method println has a type signature that is applicable to the argument of forEach. Use the reference System.out::println in the final version of the exercise.
Use method List.sort to sort the movies in order of increasing running time, using a lambda expression to define the required comparator. Move this lambda expression to a static factory method static createByTimeComparator(): Comparator<Show> and call this method as the argument to sort. Notice how this code compiles even though the type argument of the collection (Movie) and the type argument of the comparator (Show) don't match exactly.
Transform the static comparator factory from Exercise 5 into a simple static method declaration compareByTime(Show, Show):int. Then, change the code of Exercise 4 to use this method implementation instead.
Use the methods of class Comparator to create a comparator that compares movies by running time, then by title.
Turn class Movie into a Flyweight class with lazily-instantiated flyweights where the flyweight store is a Map<String, Movie> and the key is the title (assumed to be unique for this exercise). Use Map.computeIfAbsent with a lambda expression in the implementation of your flyweight object accessor method.
Write a stream-based expression that prints the running time of all movies in the database in the format: ``HH:mm` (hours, minutes). Except for the terminal operation, use only mapping operations and method references. You can define helper methods as necessary.
Write a stream-based expression that evaluates to a list that contains the three longest movies from before the year 2000, in reverse alphabetical order of title.
Use a IntStream-based expression to compute the minimum, maximum, average, and sum of a sequence of one million integers between 0 and 100 (inclusive). Do the same with double numbers (in which case 1.0 can be exclusive.
Use a flatMap operation to count the number of times the word "the" occurs in the title of any movie (ignore case).
Use a single reduce operation to obtain the longest movie in the collection.
Write a stream-based expression to create a Map<String, Integer> where the key is the title of the movie and the value is its running time. Assume movie titles are unique.
Write a stream-based expression to create a map that group movies by decade. For example, all the movies produced in the years 1950-1959 should be accessible using the key 50s, etc.
Using the map created in Exercise 14, write a stream-based expression that evaluates to a list of all the movies from the 50s and 60s.
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