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Java - Get Window Position Without Border

I'm trying to take a window screenshot to use that as background in the application.
This is my code:
try {
Robot robot = new Robot();
Rectangle captureSize = new Rectangle(new MainWindow().getX(), new MainWindow().getY(), MainWindow.getWIDTH(), MainWindow.getHEIGHT());
RenderManager.backgroundGUIs = robot.createScreenCapture(captureSize);
GUIManager.ThisGui = new GUI("inventory", null, false);
} catch(AWTException e) {
System.err.println("Error taking screenshot!");
}
And these are the MainWindow().getY() and MainWindow().getX() methods:
public int getX() {
return (int) frame.getLocationOnScreen().getX();
}
public int getY() {
return frame.getY();
}
Now... it works fine, but there is a problem. frame.getLocationOnScreen().getX() and frame.getX() return the location with the window border, that hasn't to be in the screensot. Ok, i can manually calculate border size to subtract it, but from Windows 7 to Windows 8, from Windows 8 to Mac, etc. window border changes.
So... is there a method to get frame position or window border size to calculate what i need?
Thank you for your time and your answer!

As simple as this:
x = frame.getRootPane().getX();
As well, you can make all other calculations according to the root pane, just dropping the frame's.
As expected, the root pane is the top-level container inside any Frame/Window/Dialog etc. It includes the menubar too.

Use this
frame.getContentPane().getSize();

Check out the Screen Image class. You can create an image of any component displayed on the frame.
So you could use frame.getRootPane() as the component you want the image of.
Or frame.getContentPane() if you don't want the menu bar. I think this method returns a Container object so you will need to cast is to a JComponent.

int mouseX = MouseInfo.getPointerInfo().getLocation().getX() - frame.getX() - frame.getRootPane().getX();
int mouseY = MouseInfo.getPointerInfo().getLocation().getY() - frame.getY() - frame.getRootPane().getY();
This gives the top right point within the border / tab of a frame

How do you embed a resizable JPanel inside of a JTextPane?

There are many questions of the converse, inserting a JTextPane into a JPanel. This is not my question. I need to be able to insert a custom JPanel (with drag and drop, drag, and mouse click listeners) into a JTextPane, which is then put into a JScrollPane, and finally put into a JFrame for displaying. The reason is because I need to have an image with support for resizing by dragging it within a chat client, which is itself primarily text.
Conveniently enough, there is a relevant method in JTextPane: insertComponent(Component c), but whenever I use it, my components end up being squished to exactly one line of text worth of space (even though they report having a larger size). This is perfect for plain buttons, but if I need anything larger, I'm out of luck. I can insert images by themselves just fine, with ImageIcons, but images wrapped inside a JPanel don't work at all (plus I can't add any listeners to ImageIcons, since they're not GUI elements; overriding one isn't an option).
Whenever a user drags an image into the chat client, this bit of code inserts the custom JPanel:
private void sendImage(BufferedImage im, int cl) throws IOException {
if(output == null) return;
//Send the image itself over to your friend
byte[] toSend = toBytes(im, cl);
sendString(nickname.hashCode() + "image"); //Header for image
output.writeInt(toSend.length); //Tells how many bytes to read.
output.write(toSend);
//Let the user know that the image was sent
float linmb = (float)(toSend.length / 1048576.0); //Size of file sent
addText("\n" + nickname + " sent an image! (" + linmb + " MB)\n", Color.RED.darker());
//Show the image itself
DraggerPanel d = new DraggerPanel(im, true);
text.insertComponent(d);
d.repaint();
//Spacer
addText("\n");
}
This is the source for DraggerPanel, the custom JPanel that holds an image:
public class DraggerPanel extends JPanel {
private BufferedImage image; //The image we're drawing
private Point startingPoint = null; //Starting point for resizing
private boolean first = true; //Is this the first drag?
private boolean lockedDrag; //If true, then lock x and y to be proportionally dragged.
public DraggerPanel(BufferedImage image, boolean lockedDrag) {
super();
this.image = image;
this.lockedDrag = lockedDrag;
//The listener for dragging events.
addMouseMotionListener(new MouseMotionListener() {
private int inWidth = 0, inHeight = 0; //Initial height and width values
private double ratio = 0; //Ratio of height to width for locked drag.
public void mouseDragged(MouseEvent m) {
if (first) { //If we're first, record initial position.
startingPoint = m.getPoint();
first = false;
inWidth = getWidth();
inHeight = getHeight();
ratio = (double)inHeight / inWidth;
} else { //Otherwise, change the size of the window.
if (!lockedDrag) {
int w = (int)startingPoint.getX() - m.getX();
int h = (int)startingPoint.getY() - m.getY();
setSize(Math.abs(inWidth - w), Math.abs(inHeight - h));
} else {
int w = (int)startingPoint.getX() - m.getX();
int h = (int)((double)ratio * w);
setSize(Math.abs(inWidth - w), Math.abs(inHeight - h));
}
}
repaint();
}
public void mouseMoved(MouseEvent m){
}
});
//Lets us know when you're not dragging anymore.
addMouseListener(new MouseAdapter(){public void mouseReleased(MouseEvent m){first = true;}});
//Set appropriate size.
if(image != null) setSize(image.getWidth(), image.getHeight());
else setSize(200,200);
//We're live, baby.
setVisible(true);
}
public void paint(Graphics g) {
if (image == null) super.paint(g);
else g.drawImage(image, 0, 0, getWidth(), getHeight(), null);
}
}
Update 1: I followed #camickr 's advice, and updated the DraggerPanel to use setPreferredSize instead of setSize, as well as overrode paintComponent() instead of paint(). Now, the image has the proper height, but is stretched to the width of the JTextPane (which seems like what it was doing before). Furthermore, resizing doesn't seem to matter- the image doesn't change its size at all. Mouse events are definitely going through, but not affecting the size. It seems as though the original problem isn't fully resolved, since the JPanel's size isn't what I need it to be, and the solution to that will also lead to a solution to the resizing issue.
Update 2: I did it! I finally did it. To the future time travelers who have this issue, I basically yelled at the JTextPane by not only using setSize() in my overridden JPanel, but also setPreferredSize() and setMaximumSize(). The preferred one works well with height, and the maximum sets the width (God knows why). Thanks for your tips, #camickr!

my components end up being squished to exactly one line of text worth of space (even though they report having a larger size).
I would guess the size is not important.
I would think you need to override the getPreferredSize() method of your DraggerPanel to return the preferred size of the panel so the text pane can display the panel.
Also, custom painting is done by overriding the paintComponent(...) method NOT the paint() method.

JTable resize table header does autoscroll

This is my issue. I have the code below. What it does is when I drag a column over the edge of the panel, my panel scrolls by itself.
However, the problem is, with this feature, every time I resize the column width, the panel also scrolls to the top.
For example, I have 1000 rows and I highlight the 999th row at the bottom. When I resize the column width, the panel scrolls to the top. How do I make the panel to stay at wherever I was?
I want my table to autoscroll horizontally, but not vertically.
table.getTableHeader().addMouseMotionListener(new MouseMotionAdapter() {
public void mouseDragged(MouseEvent e)
{
Rectangle r = new Rectangle(e.getX(), e.getY(), 1, 1);
((JTableHeader)e.getSource()).scrollRectToVisible(r);
table.scrollRectToVisible(r);
}
});

You are resetting JTable's scroll bar position by this statement:
table.scrollRectToVisible(r);
Here x position of rectangle is correct, as it is same for JTableHeader and JTable. But y position should be different for both. But you are using y position from JTableHeader for JTable also.
To make it work correctly, get y position of JViewPort of JScrollPane used by JTable.
Use this y position for the rectangle used in above statement. This should correct the issue.

MigLayout: how to resize the height proportionally to the width (keeping the aspect ratio)?

I'm arranging images in a grid with MigLayout. I could get the width to take the whole space available in the column, but then I want the height to grow accordingly so the proportion of the image still fixed.
What is the best approach for this? Could I do that with an expression in the constraint or I have to override the getPreferredSize()?
Thanks!

After a lot of researching, I realize that there is no nice way of doing this with Swing. The problem is not only coming from MigLayout but also from layouts like ScrollPaneLayout, which assumes that the preferred height will remain the same after a different effective width (which is not the preferred width).
There are two options:
1) Currently, I'm doing my own implementation of MigLayout with an aspect ratio component constraint. You can download it from here:
https://github.com/lqbweb/miglayout-aspect
So far, it works with shrinking and growing X in a simple grid case with 1 component / cell. I still have to test with spanning, flowing in the cell and docking..... I'll keep that repository updated and any help is well welcome.
As you will probably use it as a view on a ViewPort, you will have to hack a bit the getPreferredSize of the view if you use it with the Scrollable.getScrollableTracksViewportWidth() returning true, so it doesn't return the real preferred height but the one that matches the width. In my code there is a getter for the grid, and the grid has a function to return a preferred height for a given width.
2) Keeping the current implementation of MigLayout untouched (4.2 at the time of this answer), I only found one way to achieve this: by adding a callback to the layout and implementing getSize() method with something like this:
migLayout.addLayoutCallback(new LayoutCallback() {
/**
* This is run before the layout starts laying out
*/
#Override
public BoundSize[] getSize(ComponentWrapper comp) {
if(comp.getComponent() instanceof DCMImageWrapper) {
DCMImageWrapper img=(DCMImageWrapper) comp.getComponent(); //this is the BufferedImage embedded in a JLabel
int calculatedHeight=img.getHeightFor(comp.getWidth());
UnitValue maxHeight=new UnitValue(calculatedHeight);
BoundSize height=new BoundSize(maxHeight, maxHeight, maxHeight, null);
return new BoundSize[]{null, height};
} else {
return null;
}
}
private double getCurrentAspect(ComponentWrapper comp) {
if(comp.getWidth()==0 || comp.getHeight()==0) return 0;
double currentAspect=comp.getWidth()/(double)comp.getHeight();
return currentAspect;
}
/**
* Check if the aspect still valid
*/
#Override
public void correctBounds(ComponentWrapper comp) {
if(comp.getComponent() instanceof DCMImageWrapper) {
DCMImageWrapper img=(DCMImageWrapper) comp.getComponent();
double currentAspect=getCurrentAspect(comp);
double origAspect=img.getDCMImage().getAspect();
double currentError=Math.abs(origAspect-currentAspect);
if(currentError > img.getDCMImage().getAspectError()) {
//recalculate layout
revalidate();
}
}
}
});
and then, adding the component like:
CC constraints=new CC();
constraints.shrinkX(100);
constraints.minWidth("1");
constraints.minHeight("1");
add(tmpImg, constraints);
But, you will have to add and keep updated a layout constraint (LC) to set manually the preferred size of the layout, as after the callback it gets biased.

JAVA: size of frame and centering graphical objects

Is there anything obvious wrong with this line of code? I want rectangle to stay centered regardless the size of the window. But this don´t work for some reason, the rectangle stays the same place.
public void run() {
setSize(800, 800);
createEntireFigure();
}
private void createEntireFigure(){
int centerOfWindowWidth = getWidth() / 2;
int centerOfWindowHeight = getHeight() / 2;
GRectWithGLabel ("A String",centerOfWindowWidth, centerOfWindowHeight);
}

Your rectangle size code is only called on rectangle creation, and so it makes sense that the rectangle's position will not change if the GUI is re-sized. You need to somehow listen for size changes in your GUI and call code to re-position the rectangle then for this to work. What graphics library are you using?