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Minesweeper, how can i work on cells

I would like to create a minesweeper game. Firstly, this will work on buttons. I think I will work on two dimensional array, and there will be like boolean array that will present where are bombs, for example if booleanArray[0][4] is true, there is a bomb.
Now, how can I implement this in my buttons? I can set Names on these buttons, and then if I click some button, then I will get the name from this div. For example when i click first button, i will get "00" name, then i will get first letter "0" and second letter "0" and parse it to int. And this will be the indexes from my previous booleanArray, in this case it will be booleanArray[0][0].
So, can I do this another, better way, instead of that?
This is the way I will be creating the buttons:
for (int i = 0; i < 10; i++) {
for (int j = 0; j < 10; j++) {
JButton button = new JButton("");
button.setPreferredSize(new Dimension(50, 50));
button.setName(Integer.toString(i) + Integer.toString(j));
}
}
EDIT
I will have a two dimensional Array, that will reflect my buttons:
and now, how can I check if I hit the bomb after I click for example in the first button?

Just hold a two dimensional array of buttons,
JButton[][] myButtons = new JButton[10][10];
which you use to draw them and they all call the same method with their value
for (int x=0; x<10; x++){
for (int y=0; y<10; y++){
myButtons[x][y] = new JButton("0");
//add to page, or do it elsewhere
myButtons[x][y].addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
selectionButtonPressed(x,y);
}
});
}
}
Then a call to yout method selectionButtonPressed() will tell you what button has been pressed, you can take action and even make changes to the button with myButtons[x][y].whatever()

That is one way but you should create the String of the name by using something like:
button.setName(i + ":" j);
This will make it easier to parse out the two values as you can just use the String.split(...) method.
Another option might be to create a HashTable with the JButton as the key and then use a Point object (representing the row/column) as the value Object of the HashTable. Then you just use the get(...) method of the HashMap to retrieve the Point for the clicked button.
Another option is to extend JButton and add two parameters (row, column) when creating the button. Then you also add getRow() and getColumn() methods.
Either of this approaches will keep the logic simple and you only need to create a single ActionListener to be used by all the buttons.

removing multiple buttons with the same name

Im adding buttons for a game but when removing the button in a loop it will only get rid of one button even though i added them in the same way
for(int i=0 - 1; i < 4 ; i++) {
panelButtonsub.remove(buttonBlankItems);
}
panelButtonsub.setLayout (new GridLayout (intLayout,intLayout));
revalidate();
repaint();

If you want to remove all the buttons in the panel you can use:
panel.removeAll();
If you want to remove the first 4 buttons in the panel you can use:
for (int i = 0; i < 4, i++)
panel.remove(0);
If you are trying to remove a certain type of component from the panel then you need to start at the end to remove the components:
int components = panel.getComponentCount();
for (int i = components - 1; i >= 0; i --)
{
Component c = panel.getComponent(i);
if (c instance of BlankButton)
panel.remove(i);
}
Where BlankButton is the component you created to represent the extra space by using panel.add( new BlankButton(...) ).
If you are trying to do something else then you need to clarify your question.

You must have distinct instances for each buttonBlankItems button. I guess that you are adding the same button 5 times and then you are trying to remove them.

How do I retrieve the component type used at a specific cell in a JTable?

I've created a JTable whose columns contain a variety of different components. The last five columns either contain nothing (a DefaultTableCellRenderer with no value) or a JRadioButton using a custom renderer and editor. The renderer creates and returns a new radioButton in the cells I need one, and I want to access these radio buttons from my panel class to add them to a ButtonGroup. I am using the following piece of code that I wrote:
protected void setButtonGroups() {
buttonGroups = new ArrayList<ButtonGroup>();
for (int i = 0; i < tableModel.getRowCount(); i++) {
ButtonGroup currentGroup = new ButtonGroup();
for (int j = 0; j < tableModel.getColumnCount(); j++) {
if (table.getComponentAt(i, j) != null) {
currentGroup.add((JRadioButton)table.getComponentAt(i, j));
}
}
}
buttonGroups.add(currentGroup);
}
}
getComponentAt() keeps returning null regardless of what is contained in the cell, whether it be a JCheckBox, JRadioButton, JComboBox... everything is returned as null.
Is there an alternative way to get the cell's component? Or is there a way for me to get this to work? Thank you!

If you have a tableModel from table.getModel(). Then you can call model.getValueAt(row,col)
I am not sure why you are putting Swing Components inside a JTable. Are you using it for formatting? If so look into LayoutManagers. If you want to edit values in a table, you might want to look into extending TableCellEditor. If you really want to put components in your table. Consider extending the DefaultTableCellRenderer to return your component. You will want to override getTableCellRendererComponent().

How do I get input from buttons I created using a loop?

I'm trying to make a simple calculator in Java using Swing, and I've created my buttons the following way:
//Our number keypad
public static JPanel numbers(){
//our panel to return
JPanel panel = new JPanel();
//Create and add 3x4 grid layout to panel
GridLayout gl = new GridLayout(3, 4);
panel.setLayout(gl);
//For creating and adding buttons to panel
for(int i = 0; i < 10; i++){
//Create a new button where the name is the value of i
String name = "" + i + "";
JButton button = new JButton(name);
//add action listener
button.addActionListener(handler);
//Add button to panel
panel.add(button);
}
return panel;
}
My question is how do I reference each specific button in my event handler? I can't think of a way to do this without having to manually create each button rather than using a loop.
Thanks.

In your listener, call event.getSource(), and that will return the button which has been pressed. Get the text of the button, and you have its number.
Or create a different instance of your handler for every button, and pass the value of the button (i) to the constructor of the handler. This last solution is cleaner, IMO, because it doesn't depend on the text of the button. If you replaced the text by an image, for example, the first technique wouldn't work anymore.

You can distinguish created buttons by adding the following inside handler:
String buttonText = ((JButton) e.getSource()).getText();
if (<text1>.equals(buttonText)){
//do the stuff
} else if (<text2>.equals(buttonText)){
//do the stuff
} else {
//do the stuff
}

Method #1: go through the child components of the parent JPanel (quite tedious, has to be rebuilt every time you modify the contents of that JPanel). Make sure they're JButtons by using an if . . instanceof clause.
Method #2: as you create them in that loop, add them to a List (or even better, a Map). I prefer a Map personally as it lets me customise the key for that specific JComponent
i.e.
HashMap<String, JComponent> buttonList = new HashMap<String, JComponent>();
for(. .) {
buttonList.put("nameForEachButton", button);
}
I recommend generating the button name based off of the loop counter. Either use your existing name value, or just set it to "button" + i;

Declare your buttons using an array.
JButton[] button = new JButton[9]; //outside the for loop
for (int i = 0; i < 10; i++) {
//put your code
button[i] = new JButton(name);
//your code
}

Initialize reference variables for many objects?

I'm having a little trouble building the grids for a Battleship game for my Java class. So far, I can easily make a for loop to add JPanel or JButton objects to the JFrame. However, my issue is that I'll need to use those Panels or Buttons again when playing the game (such as clicking on a button to see if your opponent put a ship on that square, et cetera). Is there a simple way in Java to initialize reference variables for a LOT of objects? Or will I have to declare all of them individually?

You could try a multi dimensional array of JPanels (or any other object). Create an array with the same size as your grid. The line below initializes an array with 5 rows and 5 columns.
JPanel[][] battleField = new JPanel[5][5];
Use nested for loops to create the panels in the array.
for (int rowIndex = 0; rowIndex < battleField.length; rowIndex++)
{
for (int cellIndex = 0; cellIndex < battleField[rowIndex]; cellIndex++)
{
battleField[rowIndex][cellIndex] = new JPanel();
}
}
If you want to reference the battleField array later on you would just make it into a instance variable.

For a battleship game, you most likely want to retrieve the location of a button after is has been clicked. You can create a hashtable using your buttons as keys and the point it is located at as a value.
HashMap<JButton, Point> buttonMap = new HashMap<JButton, Point>();
for (int x = 0; x < COLUMNS; x++)
{
for (int y = 0; y < ROWS; y++)
{
JButton btn = new JButton();
btn.addActionListener(this);
buttonMap.put(btn, new Point(x, y));
//then add the button to your container
}
}
The in your actionPerformed method you can convert the button to the point it is located at like this.
JButton btn = (JButton)actionEvent.getSource();
Point p = buttonMake.get(btn);
Of course you will need to properly handle error conditions such as source not being a button or the button not being in the map...

You can always extend JButton to keep track of the info you need. A simple example:
class MyButton extends JButton{
private MyGameInfo mygameInfo;
private int buttonId;
//More fields....
//Getters/Setters
}
Then instead of creating and adding JButton objects to your layout, create MyButton objects(which is also a JButton so your layout will not be effected) and use its extra functionality for your game logic.

For reference, here is a related matching game that uses a grid of buttons. This related answer demonstrates the application of the Model–View–Controller pattern to a simple game.