Question

I am trying to create an array of type Library, where I can store many objects of type Library that I’ll manage later. Before I get too deep, I am trying to make a print() method on the array so that I can simply call myLibrary.print() to print the array.

public class Library {
    // Constructor

    public Library() {
    }

    public void print() {
        System.out.println("Library Sorted by Title");
    }
}

public class MediaManager {
    public static void main(String[] args) throws Exception {
        Library myLibrary[] = new Library[100];
        myLibrary.print();
    }
}

I am getting an error saying that there is no print() on Library[].

How would I go about printing this array? Would I just loop through the array in the main file and call a separate print on each object? If this is the case, where would I write custom methods to sort the array?

UPDATE

Requirements from my assignment:
“Your program will use one array of type Library to store all information read from the input file.”

“At the top level you will have a class called Library. Library will have three subclasses: Music, Book, and Movie. Music will have two subclasses: Song and Album. Book will have two subclasses: Fiction and Nonfiction. Movie, Fiction, Nonfiction, Song, and Album will not have any subclasses.”

UPDATE 2

This is for a CS-101 course. I don’t feel I should need to use Comparable.

Answer 1

In addition to defining print() method for Library; You can try following:

public void printLibrary (Library [] libraryArray) {
    for(Library library :  libraryArray) 
        library.print();
}

or if you overload toString() for Library you can simply use:

public void printLibrary (Library [] libraryArray) {
    for(Library library :  libraryArray) 
        System.out.println(library);
}

And the calling will be done like:

Library myLibrary[] = new Library[100];
printLibrary(myLibrary);

EDIT:

To sort the array you should implement Comparable<Library> in Library class and simply use

Arrays.sort(myLibrary);

to sort the array.