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Why the Item deleted from an array but isn't deleted from my table?

I've put together a few methods that are suppose to delete a searched item from an array and the data from the array is also being put into a JTable through a method called createLoginTable().
When my delete button actionListener Method is carried out the element or login is successfully deleted from the array: 'listOfLogins' but the element does not appear to be deleted from the JTable as it is still there.
Here are the methods starting with the actionListener:
if(e.getSource()==deleteLoginButton)
{
int loopNo = list.nextLogin; ///Variables used in the 'removeLogin' Method
String foundLogin = list.listOfLogins[foundLocation].toString();
Login[] loginList = list.listOfLogins;
LoginList list = new LoginList(); //The 'list' is wiped
list.removeLogin(loginList, foundLogin, loopNo);
list.writeLoginsToFile(); //Writes logins to file (not integral to the array)
String[][] loginTableLogins = new String[50][2]; //Wipes the JTable Array
createLoginsTable(); //Creates the JTable
searchLoginButton.setEnabled(true);
editLoginButton.setEnabled(false);
deleteLoginButton.setEnabled(false);
addLoginButton.setEnabled(true);
}
This is the 'removeLogin' Method (This is in a seperate 'list' class):
public void removeLogin(Login[] array, String unwantedLogin, int loop)
{
for(int i=0;i<loop;i++)
{
String currentLogin = array[i].toString();
if(!currentLogin.equals(unwantedLogin))
{
Login login = new Login();
addLogin(array[i]);
}
}
}
plus 'addLogin' Method (although i am assured this is not the source of my issue):
public void addLogin(Login tempLogin)
{
listOfLogins[nextLogin] = tempLogin;
System.out.println(listOfLogins[nextLogin]);
nextLogin++;
System.out.println(nextLogin);
}
And the 'createLoginsTable' method:
public void createLoginsTable()
{
for(int i=0;list.nextLogin>i;i++)
{
loginTableLogins[i] = list.listOfLogins[i].toArray();
System.out.println(list.listOfLogins[i].toString());
}
JTable loginsTable = new JTable(loginTableLogins, loginTableTitles);
JScrollPane loginsScrollPane = new JScrollPane(loginsTable);
loginsScrollPane.setBounds(400, 200, 200, 250);
testPanel.add(loginsScrollPane);
}
I have used 'System.out.println's so I am 99% certain that the element has been removed from the array (it is also apparent through my writeLoginsToFile Method) So I hope this information helps.

Your code is a little bit hard to decipher, next time maybe put in also the enclosing class, or some details about that class. What does the following line do:
LoginList list = new LoginList(); //The 'list' is wiped
You say the list is wiped, I think what is does is: it declares a list local variable and assigns a new object to it (and it masks the other list variable which you used a few lines earlier). Now, in the createLoginsTable() method you don't have this local variable, you have the "list" which I guess is a public field in your class. Now what you can do, is or pass the local list variable to the above function as a parameter createLoginsTable(list) or try the wiping line without the declaration so only:
list = new LoginList(); //The 'list' is wiped
Anyway, your code seams a little bit troubled it, maybe you should refactor it a little bit. Hope it helps.

You're not returning the table after you delete the item.
When you call the method to delete it and write out the table, that table is not returned after you remake the table.
Take this:
JScrollPane loginsScrollPane = new JScrollPane(loginsTable);
Bring it outside of your method. What I think might be happening is when you create your loginsScrollPane locally inside the method, it's not being added properly to your testPanel.
I think what might be happening is when you add it, and the method ends it's loosing that data that is contained. Declare your scrollpane, and your jtable where you declare your frame.

Typing Number Into JSpinner with Subclassed SpinnerListModel

I want to have a JSpinner that displays an non-patterened sequence of numbers (say, a sequence of prime numbers). This pattern is too complicated for a SpinnerNumberModel, so I decided to subclass SpinnerListModel. The constructor looks something like this:
public CustomSpinnerListModel() {
Vector<Integer> values = new Vector<Integer>();
values.add(1);
values.add(3);
values.add(5);
values.add(7);
this.setList(values);
}
This generates the model just fine and I can move through the values using the buttons on the JSpinner. However, typing a value in doesn't work. For instance, if the spinner is set to 3 and I type in 7, it remains at 3 (presumably because it doesn't think that 7 is a valid value). This works with the SpinnerNumberModel, so I'm not sure what's going on.
EDIT: I found out that if I save the numbers as string values, typing works. However, SpinnerNumberModel saves everything as Integers and that works too. So I'm not sure why my integers don't work, but SpinnerNumberModel's do.

I think the following solution is better than the suggestion to implement a Formatter, as it is not a formatting issue, but an issue of restricting the possible values, which should be the responsibility of the model. I had a similar problem and stumbling upon this threads solution, lead to a very ugly implementation. So hopefully what I came up with will keep you out of trouble.
This generates the model just fine and I can move through the values using the buttons on the JSpinner. However, typing a value in doesn't work. For instance, if the spinner is set to 3 and I type in 7, it remains at 3 (presumably because it doesn't think that 7 is a valid value). This works with the SpinnerNumberModel, so I'm not sure what's going on.
The Problem here is that setting a new model with setModel has the undocumented side effect of changing the JTextFieldEditor attribute depending on the type of the Model:
http://fuseyism.com/classpath/doc/javax/swing/JSpinner-source.html
By default, JSpinner uses a model of class SpinnerNumberModel with an editor of class DefaultNumberEditor. When you set the model to SpinnerListModel, it will instead use a ListEditor. In your case this is a bad choice, since it requires you to enter every prime number into a list to give it to the SpinnerListModel for input verification. Otherwise, as you pointed out, your input is ignored.
So the simple solution here is to subclass SpinnerNumberModel, which allows any number, instead of a specific list of values:
class PrimeNumberModel extends SpinnerNumberModel {
Object currentValue;
#Override
public Object getNextValue() {
return findNextPrimeFrom(currentValue);
}
#Override
public Object getPreviousValue() {
return findPreviousPrimeFrom(currentValue);
}
#Override
public void setValue(Object o) {
throwOnNonePrime(o); //Verify Input
super.setValue(o);
}
private void throwOnNonePrime(Object o) {
try {
int num = Integer.valueOf(o.toString());
if(!isPrime(num))
throw new IllegalArgumentException(o.toString());
} catch (NumberFormatException nfe) {
throw new IllegalArgumentException(o.toString());
}
}
}

I think you could do it with strings and then use a method to get the number.
like this:
Spinner1(){
String[] values={"1","3","5","7"};
SpinnerModel model=new SpinnerListModel(values);
JSpinner spinner=new JSpinner(model);
}
int getValue(Object obj){
int out=0;
return out=Integer.parseInt((String)obj);
}

JTextField getText() not working

I've been looking all over, and i cant find anyone who can solve this problem. I'm making a game, and in that game, i have editable controls. the controls window is a seperate JFrame, and when i click the confirm button, it is supposed to write the items in the JTextFields (holding the controls) to a file. but that wasnt working, so instead i have it print the arraylist that holds the values. here is the code:
public void writeControls() {
ArrayList<String> al = new ArrayList<String>();
al.add(up.getText());
al.add(down.getText());
al.add(left.getText());
al.add(right.getText());
al.add(jump.getText());
al.add(duck.getText());
al.add(attack.getText());
for (int i = 0; i < al.size(); i++) {
System.out.println(al.get(i));
}
System.exit(0);
}
the problem is this: if i change the final JTextField attack or any other one for that matter, and click submit, the system prints out the default controls. for example, if the JTextFields have the values w,a,s,d,r,t,q and i change the value q to i, it prints out q. what am i doing wrong? thanks in advance!
EDIT 1:
code for the textfields, and the FILES.... is simply a string stored in a different class. the class setText() is below the textfields.
up = new JTextField(setText(FILES.controlsFileFinalDir, 1));
down = new JTextField(setText(FILES.controlsFileFinalDir, 2));
left = new JTextField(setText(FILES.controlsFileFinalDir, 3));
right = new JTextField(setText(FILES.controlsFileFinalDir, 4));
jump = new JTextField(setText(FILES.controlsFileFinalDir, 5));
duck = new JTextField(setText(FILES.controlsFileFinalDir, 6));
attack = new JTextField(setText(FILES.controlsFileFinalDir, 7));
public String setText(String fileDir, int lineNum) {
String txt = "";
txt = io.readSpecificLine(fileDir, lineNum);
txt = switchCase(txt);
return txt;
}
switchcase() is only taking what you have written in the text file that these are getting the values from, and translating them. so if the value is 0, it is turned into Space, etc. io.readSpecificLine(); is only to get the line of text from the file. does this help?
EDIT 2:
i just was dinking around and found out that if i set the JTextField text by using setText(""); then use getText(); it works. so the problem is that when i change it manually, and use getText(); it wont work. Why?

To update the text to a currently existing JTextField, I would establish the JTextField as a class variable, and create a setter/getter method to adjust it (which I'm assuming you're doing).
According to your methods, you would use something like:
up.setText(setText(FILES.controlsFileFinalDir, 7));
Edit: **The first setText is the JTextField.setText, the second setText is your public method you posted. I'm assuming your second getText() isn't working because you're probably not setting the text correctly.
Without seeing more code, I can't really give a better guess.

The main possibilities:
(1) The text fields have their editable property set to false.
(2) You are creating multiple copies of the JTextFields, then editing a new one on the screen, but referring to the old one when you get the value.
(3) You have a ValueChanged or LostFocus event handler that is resetting the text fields to their defaults
(4) It is actually JFormattedTextField not a JTextField

If I was you, I would try to debug the programm. You will probably do some Mistake in your code, you won't be able to see, by just checking the code.
For example in which order do you call the functions and so on, maybe you have a fault here, or maybe you have several threads, so you try to read the Textfields without even set them and so on ... It's hard to say without reviewing the whole Code.
So if you use eclipse you can follow this link for an explanation on how to debug: http://www.vogella.com/articles/EclipseDebugging/article.html
Netbeans or any other IDE should support debugging as well.

This may seem like a strange thing to suggest, but I think this is an issue with pointers. If you create a new string before passing it in, JTextField will be able to change it internally and return what you expect when asked for the modified value.
down = new JTextField("" + setText(FILES.controlsFileFinalDir, 2));
// or
down = new JTextField(new String(setText(FILES.controlsFileFinalDir, 2)));

You might want to try the following:
create a class Test.java
import java.util.ArrayList;
import javax.swing.JTextField;
public class Test implements Runnable {
private ArrayList<JTextField> textFields = null;
private ArrayList<String> stringList = null;
public Test(ArrayList<JTextField> textFields, ArrayList<String> stringList) {
this.textFields = textFields;
this.stringList = stringList;
}
#Override
public void run() {
for ( JTextField textField : this.textFields )
this.stringList.add( textField.getText() );
}
}
and then, at the place where you use the "getText() method .. "
do the following...
ArrayList<JTextField> textFields = new ArrayList<JTextField>();
// add all the JTextField to textFields
ArrayList<String> stringList = new ArrayList<String>();
Test test = new Test( textFields, stringList );
SwingUtilities.invokeLater( test );
// check if the stringList is populated.
If this work, then what I believe is that, for some reason, the JTextField hasn't finished
"setting" the text, and before it finishes your getText() was called. I've had similar problems before, and this solved my problem that time, but still, this might not be the perfect solution.

First, you should change your "setText()" method name to something like "getTextFromFile()" it would be more readable
Then, if you are setting and reading the new text in different threads, my bet is that the setText() is taking long to return, because it is accessing the file system, while the method that read the values run instantly
I would try to do run a little test:
public void test(){ // must be run after the JTextFields be initialized
up.setText("TEST")
System.out.println(up.getText());
up.setText(setText(FILES.controlsFileFinalDir, 1));
System.out.println(up.getText());
}
If the test() prints the correct values, then we can assume that if you set and read the new value in the same thread it works fine
The other test I would do is:
public void testThread(){
new Thread(){
public void run(){
while(true){
if(up!=null){
System.out.println(up.getText());
}
try{
Thread.sleep(1000);
}catch(Exception e){
e.printStackTrace();
}
}
}
}.start();
}
It will print the value of up each 1 second, so that you can see if after some time you get the new value. If it does, then the answer is: Your setText() is taking long to run and you are reading the value before the new value is set

SOLUTION
none of the above answers were working for me, so i finally decided to just start over with that class. the few things i changed were the way i made the JTextFields. I made them as an array instead of individual objects. Second is the way i put what they say. When i initialized them, i was unable to get them to create WITH the text in the parameters. so i had to do that seperately. i changed some of the method names so as to reduce future confusion, and it worked! so im not sure what was up with that, maybe it was the way i did it, maybe just a fluke. it happens sometimes, so im sorry for the delay and waste of your time! thanks for all the answers anyway!

Try this:
textbox.setText(setFile(args)); // your function for set file

Persisting object value in Java Swing application

I have a swing UI having two buttons : 1. Loading database values to Hashmap 2. Comparing input values to database values.
Previously both the operations were done using the same button so the Hashmap was getting populated and the inputs were compared correctly. But now its not so.
After debugging I came to know that the hashmap values are null as the values are lost during the second operation.
How to approach this problem. So that the hash map values persist while i click the second button.
Code Example:
Button1: Loading-
LoadMaps = new JButton( new AbstractAction("LoadMaps") {
#Override
public void actionPerformed( ActionEvent e ) {
DRGCalc t = new DRGCalc();
t.loadHashMaps();
}
});
Button2: Calculation-
public void actionPerformed(ActionEvent evt) {
DRGCalc d = new DRGCalc();
int i = d.calculateDRG(Codes);
}
As t and d are two seperate objects so the values in t wont persist when I am clicking d. For this I have included the method used in button 1 inside the calulateDRG call and its working fine but I want both to be separate. How to do this?
Thanks

DRGCalc t = new DRGCalc();
This object only exist within the ActionListener. If you want the object to be available to other ActionListeners or other methods in your class then you need to make it a class variable. So in your class you need to define:
DRGCalc t;
Then in the ActionListener you change the code to:
t = new DRGCalc();

Java: linked list of items problem

I have used linked lists before with Strings, doubles, etc., and they always worked exactly as expected. But now I am forming a linked list of items, and whenever I add a new element to the list, all objects in the list apparently become equal to the last object.
The essential code is as below:
import java.util.*;
public class Global
{
static public LinkedList<StockInfo> DiaryStocks = new LinkedList<StockInfo>();
static public class StockInfo //info related to each stock in diary
{
String recordDate;
String ticker;
int status;
String buyDate;
String sellDate;
double buyPrice;
double sellPrice;
double nmbrShares;
}//StockInfo
//The following function places the Diary data for a stock in the arraylist
static public void AddDiaryData(StockInfo thisdata)
{
String tckr;
int i;
DiaryStocks.add(thisdata);
for (i = 0; i < DiaryStocks.size(); i++) //this is debug code
{
tckr = DiaryStocks.get(i).ticker;
}
}
}
As I said, when single stepping through the debug code near the bottom, each time I add a new item to the list, the list size grows as it should, but the tckr item only corresponds to the last item added.
Any insights into this puzzle would be greatly appreciated.
John Doner

The problem is outside the code your provide. It is most likely that you are adding the same instance of StockInfo. Perhaps you have something like:
StockInfo info = new StockInfo();
for (...) {
info.setFoo(..);
info.setBar(..);
AddDiaryData(info);
}
You should not reuse instances like that. You should create a new instance each time.
As a sidenote - method names in Java should start with lowercase letter.

From the symptoms you are describing, it seems as if you are always adding a reference to the same StockInfo object instance to your list, rather than a reference to a new copy each time.
When that object is updated with the contents of the new entry, all list entries appear to change to reflect that latest entry.
This problem lies outside the code snippet that you posted, perhaps in the caller of the AddDiaryData method.

Ooops.
Deep Copy please search it
DiaryStocks.add(thisdata);
you should create new StockInfo() then add to the list otherwise you add the reference and it equalize all the reference of items to the last one