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How many JLabels fit in my JPanel

I'm trying to fill a JPanel with a neat grid containing as many JLabels as will fit into the JPanel. The size of the JPanel can vary, and the size of the JLabels depends on the label text, the icon included in the JLabel, and the font being used to render the label text.
GridLayout myLayout = new GridLayout();
JPanel myPanel = new JPanel(myLayout);
List<JLabel> myLabels = ...
int panelWidth = myPanel.getWidth();
int panelHeight = myPanel.getHeight();
if (panelWidth == 0 || panelHeight == 0) return;
int maxLabelWidth = 0, maxLabelHeight = 0;
for (JLabel label : myLabels) {
int labelWidth = ???
int labelHeight = ???
if (labelWidth > maxLabelWidth) maxLabelWidth = labelWidth;
if (labelHeight > maxLabelHeight) maxLabelHeight = labelHeight;
}
// Use panelHeight, panelWidth, maxLabelHeight and maxLabelWidth to compute
// rows and columns available for myLayout
myLayout.setRows(nRows); myLayout.setColumns(nColumns);
for (JLabel label : myLabels) {
myPanel.add(label);
// stop if we reach nRows*nColumns labels
}
I've tried myPanel.getGraphics().getFontMetrics().getHeight() to get the height of text, but when the font is large and myPanel is small, the text is taller than labelHeight, and the bottom and top get cut off.
I've tried label.getIcon().getIconHeight() to get the height of the icon, but using this value always cuts off the top and bottom of the icons.
I've tried label.getSize() to get the height and width of the JLabel, but that usually returns 0 height and 0 width. I've tried label.getPreferredSize() but that generally returns a value that's too small.
I've tried label.getGraphics().getFontMetrics().stringWidth(label.getText()) to get the width of the string, and then added that to label.getIcon().getIconWidth() and label.getIcon().getIconTextGap() but that comes up with a value a little larger or smaller than label.getPreferredSize(), and in any case still too small - sometimes the label text is cut off at the end.
At one point I tried adding a constant to each width and height; that prevented cut-off text and icons, but of course it left too much blank space around the JLabels. Is there a way to get an accurate size for each JLabel for this usage?

Fit setIcon to JButton Array

I know this has been asked a ton of times, but I've searched everywhere and still haven't found an answer. I'm relatively new to Java. I have
JButton b[][];
Later, I assign b[3][3].setIcon(path). However, the image at path is always a small section of the actual image the size of the JButton. What I want is to re-size the image to fit the size of the JButton. Is there any way to do this? By the way, here's some code that's (I think) is important:
int n = 8;
int m = 8;
...
b = new JButton[n][m];
setLayout(new GridLayout(n,m));
for (int y = 0;y<m;y++){
for (int x = 0;x<n;x++){
b[x][y] = new JButton(" ");
b[x][y].addActionListener(this);
add(b[x][y]);
b[x][y].setEnabled(true);
}
}

What I want is to re-size the image to fit the size of the JButton.
You can use the Stretch Icon class.
It will allow you to automatically resize the Icon:
to fill the space of the button, or
keep the Icon proportion and fill the space of the button
The resizing is done dynamically so you don't need scaled images.

What you obviously need is a Icon Resizer method, something in the way of what I have provided below:
public static Icon resizeIcon(ImageIcon icon, int resizedWidth, int resizedHeight) {
Image img = icon.getImage();
Image img = img.getScaledInstance(resizedWidth, resizedHeight, java.awt.Image.SCALE_SMOOTH);
return new ImageIcon(img);
}
You can call this method after the image has already been applied to the JButton and after it has been added to whatever panel:
b[3][3].setIcon(path)
b[3][3].setIcon(resizeIcon((ImageIcon) b[3][3].getIcon(),
b[3][3].getWidth() - 15, b[3][3].getHeight() - 15));
or you could do it this way:
ImageIcon img = new ImageIcon("MyImage.png");
Icon icn = resizeIcon(img, b[3][3].getWidth() - 15, b[3][3].getHeight() - 15);
b[3][3].setIcon(icn);

Resizing GridLayout area

I have a 4x4 gridlayout and I'm trying to add 2 title bars above the tables I've created. I'm creating panels for title bars but because of the gridlayout it fills up all the space. Here's the code:
private WebScrollPane createPosRiskPanelWindow(int w, int h)
{
//Content area
posRiskPanel = new WebPanel((new GridLayout(2,2)));
posRiskPanel.setBackground(Color.WHITE);
//Add title bars
WebPanel posTitle = new WebPanel(new WebLabel("Current Positions"));
posRiskPanel.add(posTitle);
WebPanel riskTitle = new WebPanel(new WebLabel("Risk Exposure"));
posRiskPanel.add(riskTitle);
//Panels
CreatePositionPanel(posRiskPanel);
CreateRiskParamsPanel(posRiskPanel);
//Scroll content
posRiskScroll = new WebScrollPane (posRiskPanel, false);
posRiskScroll.setPreferredSize (new Dimension (w, h));
return posRiskScroll;
}
And here's what it looks like:
Is there a way I can resize those top 2 boxes?

Don't use GridLayout for the overall layout, since the only thing it knows to do is to create cells that are all exactly the same size. Since you don't want this, your GUI will require a different layout. Instead use GridBagLayout or else you could use nested JPanels with differing layouts, but I think that GridBagLayout for the overall layout is likely your best bet here. Other considerations include MigLayout if you're willing to use a 3rd party library.

I found it easier to just put the tables in their own panel and a titled border like so:

How can I have my top level Jpanel set its location relative to a jlabel that is in another jpanel's grid?

The scenario: I have a UI that contains a JPanel (call it topGrid) with a grid layout in a JFrame at the top level. Within topGrid, I have placed another JPanel (midGrid) with grid layout. Inside midGrid, is another JPanel (bottomGrid) that has a JLabel that I populate with images depending on an array and what their instance is within that array.
The goal: I would like the topGrid to center its view on a specific object found in bottomGrid. (Picture a game that as the player icon moves, the game's grid moves to center on that icon and also when the game is started it is already centered for the user.)
I've considered getting the Point from bottomGrid and trying to pass it over to topGrid but doesn't seem to pull the correct information. The only way i know to find where the player is, is to iterate through all the components and check instances. this would have to be done once for the topGrid and again for midGrid to find the player at bottomGrid. then pass the Point data. Then use setLocation() on the appropriate JPanel minus the distance from the center.
Has anyone else tried this and have a more effective or elegant way to go about it? What other options could I explore?
Thanks for any feedback.
Creating the grid within topGrid's JPanel:
public void createTopGrid()
{
int rows = galaxy.getNumRows();
int columns = galaxy.getNumColumns();
pnlGrid.removeAll();
pnlGrid.setLayout(new GridLayout(rows, columns));
for (int row = 0; row < rows; row++)
{
for (int col = 0; col < columns; col++)
{
Position pos = new Position(galaxy, row, col);
Sector sector = galaxy.getSector(pos);
GalaxySector sectorUI = new GalaxySector(sector);
pnlGrid.add(sectorUI);
}
}
}
Creating the grid within midGrid's JPanel:
public void createOccupantIcons()
{
pnlGridOccupants.removeAll();
Occupant[] occs = sector.getOccupantsAsArray();
for ( Occupant occ : occs )
{
GalaxyOccupant occupant = new GalaxyOccupant(occ, sector);
pnlGridOccupants.add(occupant);
}
}
The Image icons for each occupant in the midGrid are pulled from an IconRep String in the model in the bottomGrid class' JPanel and added into a JLabel as needed in FlowLayout.
For visual reference:
Where green square is topGrid JPanel, red squares are midGrid JPanel, and the black square is the bottomGrid JPanel with the white circle for the player image inside a JLabel. The blue circle represents a viewport the user will see the game through and is where I want the player icon to be centered to. Currently the user can move the grid's using very inelegant buttons in the area around the viewport. That might be sufficient but at the start of the game the player has to move the grid around until they can locate their icon.

You might also look at JScrollNavigator, examined here. It would allow you to navigate on a thumbnail image of your entire world, seen at full size in an adjacent scroll pane.

Off the top of my head, I would store all the references you want to in some kind of model.
You could use this model to update the views based on selection requirements.
This allows the you to centralise the logic for finding and updating the elements without knowing or caring out the other UI elements

JLabel Width Independent from Text Length

I have a JLabel in a horizontally re-sizable JPanel. The JLabel auto re-sizes its width to fit the JPanel. If I insert a long line of text (such as "aaaaaaaaaaaaaaaaaaaaaaaa") the JLabel doesn't truncate the text. Instead, the width re-sizes to fit the text, causing also an ugly re-sizing of the JPanel.
Instead, I want my text to be truncated with an elipse (...). The JLabel width must not inherit from the text's length but only from the JPanel width.

Try following:
final JLabel label = ...
...
label.setText("prototype text to define size");
final Dimension size = label.getPreferredSize();
label.setMinimumSize(size);
label.setPreferredSize(size);
...
label.setText(...);

Use a different layout or set a max size on the JLabel.

You need to disable 'Horizontal Resizable' when you define a max- and preferedsize