JUnit Test Driven Development for a shell program

I need to design a JUnit test that will test the functionality of the file Book.Java. I have included the test file that I have made thus far, but it is coming back as failing the necessary tests, and I am not sure as to why. This is for a Test Driven Development. I think I have the implementation mostly correct, but I need to know where I am lacking. Also, I am not sure how he is going to implement the boolean, so it leaves me unsure as to how to set up the test. I have completed parts of the program so that I can test my code, and most of it is working. I just need some advice on where I need to go from here.

Book.java

package edu.odu.cs.cs350;

import java.util.Iterator;

/**
* A book object as it might be recorded in a publisher's catalog or a 
library.
* 
* <p>
* This is not a capture of the contents of the book, but of the metadata 
that
* describes the book: authors, title, etc.
* 
* @author zeil
*
*/
public class Book implements Cloneable, Iterable<Author> {

private String title1;
String publisher1;
String isbn1;

/**
 * Create a "blank" book with empty strings for title, publisher, ISBN and
 * an empty (zero-length) list of authors.
 */
public Book() {
    title1 = "";
    publisher1 = "";
    isbn1 = "";
}

/**
 * Create a new book.
 * 
 * @param title
 *            title of the book
 * @param publisher
 *            publisher of the book.
 * @param isbn
 *            ISBN identifier for the book.
 * @param authors
 *            list of authors for this book.
 */
public Book(String title, String publisher, String isbn, Author[] authors) {
    // TODO
}

/**
 * Get the title of this book.
 * 
 * @return the title
 */
public String getTitle() {

    return this.title1;
}

/**
 * Set the title of this book.
 * 
 * @param title
 *            the title to set
 */
public void setTitle(String title) {
    this.title1 = title;
}

/**
 * Get the ISBN of this book.
 * 
 * @return the ISBN
 */
public String getISBN() {

    return this.isbn1;
}

/**
 * Set the ISBN of this book.
 * 
 * @param isbn
 *            the isbn to set
 */
public void setISBN(String isbn) {
    this.isbn1 = isbn;
}

/**
 * Get the publisher of this book.
 * 
 * @return the publisher
 */
public String getPublisher() {
    // TODO
    return this.publisher1;
}

/**
 * Set the publisher of this book.
 * 
 * @param publisher
 *            the publisher to set
 */
public void setPublisher(String publisher) {
    this.publisher1 = publisher;
}

/**
 * How many authors does this book have?
 * 
 * @return number of authors
 */
public int numAuthors() {
    // TODO
    return 0;
}

/**
 * Add an author to the end of the books's list (if that author is not
 * already in there).
 * 
 * @param au
 *            author to be added
 */
public void addAuthor(Author au) {
    // TODO
}

/**
 * Render the book as a string in a format guaranteed to contain all fields.
 */
public String toString() {
    // TODO
    return "";
}

// Comparison and hashing

/**
 * Compares two books for equality. They are considered equal if they have
 * the same ISBN.
 *
 * @param obj
 *            object to be compared for equality with this duration
 * @return <tt>true</tt> if the specified object is equal to this one
 */
public boolean equals(Object obj) {
    // TODO
    return false;
}

/**
 * Returns the hash code value for this object.
 *
 * @return the hash code value for this book
 */
public int hashCode() {

    return (2 * this.title1.length() + 4 * this.isbn1.length() + 8 * this.publisher1.length());

}

/**
 * Return a (deep) copy of this object.
 */
@Override
public Object clone() {
    // TODO
    return null;
}

/**
 * Provide access to the list of authors. e.g., Book book = new Book(...);
 * for (Author au: book) { doSomethingWithAuthor (au); }
 * 
 * @return iterator over the authors.
 */
public Iterator<Author> iterator() {
    // TODO
    return null;
}

}

Author.java

package edu.odu.cs.cs350;

/**
* An author of a book. Currently, this contains only the author's name.
* 
* @author zeil
*
*/
public class Author implements Cloneable, Comparable<Author> {

/**
 * The surname ("family name") of this author.
 */
private String surname;

/**
 * The given name ("personal name" or "first name") of the author.
 */
private String givenName;

/**
 * Create an author.
 * 
 * @param givenName
 *            the personal name of the author
 * @param surname
 *            the family name of the author
 */
public Author(String givenName, String surname) {
    this.givenName = givenName;
    this.surname = surname;
}

/**
 * Compare two authors for equality.
 * 
 * @param obj
 *            another author
 * @return true ff they have the same name
 */
public boolean equals(Object obj) {
    if (obj instanceof Author) {
        Author au = (Author) obj;
        return givenName.equals(au.givenName) && surname.equals(au.surname);
    } else {
        return false;
    }
}

/**
 * Get the name of the author in a form suitable for sorting. surname,
 * givenName
 * 
 * @return sortable name of the author
 */
public String getSortingName() {
    return surname + ", " + givenName;
}

/**
 * Return the author's name in conventional form. givenName surname
 */
public String toString() {
    return givenName + " " + surname;
}

/**
 * Return the surname of this author
 * 
 * @return the surname
 */
public String getSurname() {
    return surname;
}

/**
 * Return the given name of this author
 * 
 * @return the given name
 */
public String getGivenName() {
    return givenName;
}

/**
 * Compare this author to another, returning a negative value if this author
 * should follow the other in a sorted list, zero if they are equal, and a
 * positive value if this author should precede the other in a sorted list.
 * 
 * @param au
 *            the other author to be compared against.
 * @return number whose sign indicates the comparison result
 */
public int compareTo(Author au) {
    return getSortingName().compareTo(au.getSortingName());
}

}

TestBook.java

package edu.odu.cs.cs350;

import static org.junit.Assert.*;
import org.junit.Test;
public class TestBook {

@Test


public void testSetTitle()
{
    Book title = new Book();
    int oldHashCode = title.hashCode();
    title.setTitle("abcde");
    assertEquals( "abcde", title.getTitle());
    assertEquals("", title.getISBN());
    assertEquals("", title.getPublisher());
    assertNotEquals(oldHashCode, title.hashCode());

}

@Test

public void testSetISBN()
{
    Book ISBN = new Book();
    int oldHashCode = ISBN.hashCode();
    ISBN.setISBN("123-456-789");
    assertEquals("123-456-789", ISBN.getISBN());
    assertEquals("", ISBN.getTitle());
    assertEquals("", ISBN.getPublisher());      
    assertNotEquals(oldHashCode, ISBN.hashCode());


}



@Test

public void testDuplicateISBN()
{
    Book newBook = new Book();
    int oldHashCode = newBook.hashCode();
    newBook.setISBN("123-456-789");
    Book Repeat = new Book();
    Repeat.setISBN("123-456-789");

    assertNotEquals(oldHashCode, newBook.hashCode());
    assertNotEquals(Repeat.getISBN(), newBook.getISBN());

}

@Test

public void testSetPublisher()
{
    Book Publisher = new Book();
    int oldHashCode = Publisher.hashCode();
    Publisher.setPublisher("abcde");

    assertEquals("abcde", Publisher.getPublisher());
    assertEquals("", Publisher.getTitle());
    assertEquals("", Publisher.getISBN());
    assertNotEquals(oldHashCode, Publisher.hashCode());

}


@Test

public void testAddAuthor()
{
Author Auth = new Author("abc", "def");
Book test = new Book();
test.addAuthor(Auth);

assertEquals("abc", Auth.getGivenName());
assertEquals("def", Auth.getSurname());
assertEquals("def, abc", Auth.getSortingName());
}

}