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Thread: Exception in thread "main" java.lang.NullPointerException (HELP!!!)

  1. #1
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    Post Exception in thread "main" java.lang.NullPointerException (HELP!!!)

    Im new in JAVA language... But I need help urgently in this code now.. I got these errors:
    Exception in thread "main" java.lang.NullPointerException
    at sun.misc.FloatingDecimal.readJavaFormatString(Floa tingDecimal.java:1838)
    at sun.misc.FloatingDecimal.parseDouble(FloatingDecim al.java:110)
    at java.lang.Double.parseDouble(Double.java:538)
    at Library.Main.loadMembers(Main.java:994)
    at Library.Main.main(Main.java:40)
    when i compile these codes:

    public static void main(String[] args) throws IOException{
            boolean save = false;
            DisplayMenu();
            String pathPrefix = getPathPrefix();
            Library library = loadLibrary(pathPrefix);
    (Main.java:40)     Member[] members = loadMembers(pathPrefix);
            Book[] books = loadBooks(pathPrefix);
            if(askpassword (library)){
                save = MainMenu(pathPrefix, library, members, books);
            }
            else
                System.out.println("Password invalid. Please try again.");
     
            if(save)
                saveProject(pathPrefix, library, members, books);
            System.exit(0);
        }
     
     public static Member[] loadMembers(String pathPrefix) throws IOException{
            SAXBuilder builder = new SAXBuilder();
            String path = pathPrefix + "libraryMembers.xml";
            File memberXMLFile = new File(path);
            while (! memberXMLFile.exists()){
                path = askForFile(path,"Members XML File");
                memberXMLFile = new File(path);
            }
     
            try{
                Document document = (Document) builder.build(memberXMLFile);
                Element rootNode = document.getRootElement();
                List list = rootNode.getChildren("member");
     
                Member[] members = new Member[list.size()+10];
                //initialize entire member array
                for (int i = 0; i < members.length; i++)
                    members[i] = new Member();
                for (int i = 0; i < list.size(); i++){
                    Element node = (Element) list.get(i);
                     members[i].setisSet();
                     members[i].setfName(node.getChildText("fname"));
                     members[i].setlName(node.getChildText("lname"));
                     members[i].setAdd(node.getChildText("Add"));
                     members[i].setPhone(node.getChildText("Phone"));
                     members[i].seteMail(node.getChildText("eMail"));
                    //members[i].setRestrictedTo(node.getChildText("restrictedTo"));
                     members[i].setmemberStatus(node.getChildText("memberStatus"));
                     members[i].setBirthday(node.getChildText("Birthday"));
    (Main.java:994)  members[i].setfine(Double.parseDouble(node.getChildText("fine")));
                     members[i].setspeFine(Double.parseDouble(node.getChildText("speFines")));
                    //members[i].setCheckBooks(Integer.parseInt(node.getChildText("checkedBooks")));
     
                    //set checkedbooks
                    String checkedBooksString = node.getChildText("Check Books");
                    String[] checkedBooksStringArray = checkedBooksString.split(",");
                    int[] checkedBooks = new int[checkedBooksStringArray.length];
                    for (int checkedBook = 0; checkedBook < checkedBooksStringArray.length; checkedBook++){
                        if (checkedBooksStringArray[checkedBook].equals(""))
                            continue;
                        else
                            checkedBooks[checkedBook] = Integer.parseInt(checkedBooksStringArray[checkedBook]);
                    }
                    members[i].setcheckBooks(checkedBooks);
     
                }
                return members;
            } catch (JDOMException jdomex) {
                System.out.println(jdomex.getMessage());
            }
            return null; 
        }

    Need help!!! Your help will be appreciate
    Last edited by Savage; July 31st, 2014 at 09:50 AM.


  2. #2
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    Default Re: Exception in thread "main" java.lang.NullPointerException (HELP!!!)

    What line is the error being thrown from? (Looks like line 40 of your program)

    What are the values of every variable on that line? Use a debugger, or at least some print statements, to answer that question.
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    Default Re: Exception in thread "main" java.lang.NullPointerException (HELP!!!)

    Hi. Im not quite understand your question. Would please explain in more detailed?
    Sorry.

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    Default Re: Exception in thread "main" java.lang.NullPointerException (HELP!!!)

    Look at the stack trace to figure out what line of your program is causing the Exception.

    Go to that line. What is that line? What variables are on that line? When that line executes, what are the values of each of those variables?
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