Creating a Library, abstract class created issues. Also need GUI help.

[rplee18]

I am still in my first few months of programming so please bear with me if the problems are stupid-easy to fix.

When I changed the the Books file to an Abstract class, it created a few compatibility issues. I fixed most, but there are still a couple of errors that I can't wrap my head around.

Also, when I list the books, it doesn't show in the GUI, and also errors should show in a JOptionPane I guess, not sure. :/

Help would be greatly appreciated! Hope to have a positive first experience on this website

[Norm]

Please post the code you are working on here on the forum.

there are still a couple of errors

Please copy the full text of the error messages and paste it here.

Be sure to wrap your code with code tags:
[code=java]
<YOUR CODE HERE>
[/code]
to get highlighting and preserve formatting.

[rplee18]

First error: no suitable method found for add(StringTokenizer)

	//READ FROM FILE
	public void LibraryRead()
	{
		libraryBooks.clear();
 
	   	try
	   	{
	     	FileReader fr = new FileReader("Library.txt");
	    	BufferedReader br = new BufferedReader(fr);
 
	     	String stringRead = br.readLine();
 
	     	while( stringRead != null )
	     	{
	       		StringTokenizer st = new StringTokenizer(stringRead, ", ");
 
	       	   	String title = st.nextToken();
	       		String author = st.nextToken();
	       		String form = st.nextToken();
 
	       		libraryBooks.add(st); //ERROR LINE
 
	      		stringRead = br.readLine();
	     	}
	     	br.close();
	   	}
 
	   	catch(FileNotFoundException fnfe)
	   	{
 
	     	System.out.println("ERROR: Unable to find Library.txt");
	   	}
 
	   	catch(IOException ioe)
	   	{
	     	ioe.printStackTrace();
	   	}
	}

Second error: Book is abstract; cannot be instantiated

	//WRITE TO FILE
	public void LibraryWrite (String title, String author, String form)
	{
		boolean bookExists = false;
 
	  	try
	   	{
	       	Scanner scan = new Scanner( System.in );
 
		FileWriter fw = new FileWriter( "Library.txt", true);
	       	BufferedWriter bw = new BufferedWriter(fw);
 
	       	ArrayList<Books> LibraryWrite = new ArrayList<Books>();
	       	LibraryRead();
 
			for(Books checkBooks : libraryBooks)
			{
				if(checkBooks.getTitle().equals(title) &&   checkBooks.getAuthor().equals(author))
				{
					bookExists = true;
				}
			}
 
			if(bookExists)
			{
				System.out.println("ERROR: Book already exists.");
			}
 
			else
			{
				Books newBook2 = new Books(title, author, form); //ERROR LINE
				LibraryWrite.add(newBook2);
 
				for (Books book : LibraryWrite)
				{
					bw.write(book.getTitle() + ", " + book.getAuthor() + ", " + book.getForm() + "\r\n");
					System.out.println(book);
				}
				bw.close();
 
	        	System.out.println("SUCCESS! File has been written.");
			}
		}
 
	   	catch( IOException ioe )
	   	{
	      	ioe.printStackTrace( );
	   	}
	}

[Norm]

no suitable method found for add(StringTokenizer)

The compiler could not find an add() method that took a StringTokenizer object as an arg.

Book is abstract; cannot be instantiated

You can not create an instance of an abstract class.