⌛⌛ Movie data vs stream

Place your code into files named Movie.java and MovieAnalytics.java in the directory Round7/streams. Also remember to pull task material from student_template_project.

This task concerns basic use of Java streams. The goal is to implement a class MovieAnalytics that offers functions for reading movie data from a file and then processing the data with Java streams. You also need to implement a simple class Movie for representing movie data.

Implement these two classes as follows:

  • The class Movie should have the following public features:

    • Constructor Movie(String title, int releaseYear, int duration, String genre, double score, String director) that initializes the object to holds the information provided by the constructor parameters: movie title, release year, duration, genre, rating score and director.

    • Getter functions for all these: e.g. getTitle(), getReleaseYear(), and so on.

  • The class MovieAnalytics should have the following public features:

    • Constructor MovieAnalytics() that initializes an empty movie database. E.g. a simple Movie list will suffice for this task.

    • Static member function Consumer<Movie> showInfo() that returns an object that implements the interface Consumer<Movie> and whose function accept(Movie t) prints out information of the movie t in the form “title (By director, releaseYear)\\n” (see the example output files for details).

    • Member function void populateWithData(String fileName) that reads movie data from the file spedicifed by the parameter.

      • The file is expected to contain lines of form “title;releaseYear;duration;genre;score;director”. That is, each line describes one movie and includes the same set of information that the constructor of Movie takes as parameters.

        • A straight-forward split operation using a semicolon as a separator will work fine. Then you just need to convert some parts into suitable numbers.

    • Member function Stream<Movie> moviesAfter(int year) that returns a stream that lists all movies released in the year year or later.

    • Member function Stream<Movie> moviesBefore(int year) that returns a stream that lists all movies released in the year year or earlier.

    • Member function Stream<Movie> moviesBetween(int yearA, int yearB) that returns a stream that lists all movies released between the years yearA and yearB (including also yearA and yearB).

    • Member function Stream<Movie> moviesByDirector(String director)``that returns a stream that lists all movies directed by ``director.

The last four functions must return a stream that lists the movies in ascending order of release year. Movies with the same release year are orderd by title (using the natural String order).

A note about returning a stream: return a stream that has been set to perform intermediate (but no terminal) operations. E.g a stream that lists the unique items of the array int[] ia = [1, 2, 5, 4, 2, 5, 4] in sorted order could be created and returned as return Arrays.stream(ia).distinct().sorted();. The recipient of this stream could then read the values 1, 2, 4 and 5 from the stream.

Testing

You may test your implementation by using the test program given in the file MovieTest.java and the example output given in the files output1.txt, output2.txt and output3.txt. Place these files to the same directory with your code, compile the test program e.g. as javac *.java, and run the tests as java MovieTest input1.txt, java MovieTest input2.txt and java MovieTest input3.txt. The expected outputs of these tests are given in the files output1.txt, output2.txt and output3.txt.

A+ presents the exercise submission form here.