Lesson 8

[Joseph Evans]

I am working through lesson 8. At about 4:30 you use quick fix to create two methods in Book.java. The setPerson seems to work just fine however when I have quick fix create the getPerson method it adds a statement underneath,

return null;

After saving, BookTest shows no errors but when I test it fails and gives me a message:

java.lang.NullPointerException

Sorry, but I am stumped. I am using Eclipse 3.4.1.

Book.java follows:
package org.totalbeginner.tutorial;

public class Book {

    public String title;
    public String author;

    public Book(String string) {
        this.title = string;
        this.author = "unknown author";
    }

    public String getAuthor() {
        return author;
    }

    public void setAuthor(String author) {
        this.author = author;
    }

    public String getTitle() {
        return title;
    }

    public void setPerson(Person p2) {
        // TODO Auto-generated method stub
       
    }

    public Person getPerson() {
        // TODO Auto-generated method stub
        return null;
    }

}

BookTest.java follows:

package org.totalbeginner.tutorial;

import junit.framework.TestCase;

public class BookTest extends TestCase {

    public void testBook() {
        Book b1 = new Book ("Great Expectations");
        assertEquals("Great Expectations", b1.title);
        assertEquals("unknown author", b1.author);
       
    }
       
    public void testGetPerson() {
        Book b2 = new Book("War and Peace");
        Person p2 = new Person();
        p2.setName("Elvis");
       
        //method to say to whom the book is loaned
       
        b2.setPerson(p2);
        //get the name of the person who has the book
       
        Person testPerson = b2.getPerson();
        String testName = testPerson.getName();
       
        assertEquals("Elvis", testName);
    }
}

Thanks for looking and helping. There is nothing else like this that I have found and I am most appreciative.

Bryant
   

[Joseph Evans]

Still not sure why it failed the JUnit test at that point when it passed on yours, however when I finished the coding for the lesson it worked fine and passed the test.

I may be too focused on the moment to moment instructions. I'll finish the lessons before asking again.

Thanks