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(Java Swing) Having a problem with layouts

I am fairly new to java and programming overall. I've read quite an amount of information and watched a lot of videos about layouts, but even then upon my first try to make a program my screen goes all empty.
I am trying to make two panels for different usage and I am trying to add components to the sides (Left: one north panel will be used for buttons, Right: north, east and south panels will be used for buttons).
Here is the code:
public class SNGUI {
public JFrame f = new JFrame();
JPanel panelright = new JPanel(); //contains UT/LWmenu/MetaMenu
JPanel panelleft = new JPanel(); //contains TextArea document / TextEditors
JPanel TextEditorsPanel = new JPanel();
JPanel UpperToolsPanel = new JPanel();
JPanel LowerToolsPanel = new JPanel();
JPanel SettingsPanel = new JPanel();
public SNGUI() {
//Frame characteristics
f.setTitle("Study Notes v 0.00.0");
f.setSize(1440,900);
f.setExtendedState(JFrame.MAXIMIZED_BOTH);
f.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
f.setLayout(new GridLayout(1,2));
f.setResizable(true);
f.setVisible(true);
// Main panel layouts
panelright.setLayout(new BorderLayout());
panelleft.setLayout(new BorderLayout());
// Additional panel layouts
//TextEditors.setLayout(new FlowLayout(FlowLayout.LEADING,0,0));
// Lower Tools Buttons
LTButtons[0] = new JButton("Calculator");
// colors (delete later)
panelleft.setBackground(Color.yellow);
panelright.setBackground(Color.DARK_GRAY);
TextEditorsPanel.setBackground(Color.GREEN);
UpperToolsPanel.setBackground(Color.blue);
LowerToolsPanel.setBackground(Color.cyan);
SettingsPanel.setBackground(Color.pink);
//panelright.setPreferredSize(new Dimension(1000,100));
panelleft.add(TextEditorsPanel, BorderLayout.NORTH);
panelright.add(UpperToolsPanel, BorderLayout.NORTH);
panelright.add(LowerToolsPanel, BorderLayout.SOUTH);
panelright.add(SettingsPanel, BorderLayout.EAST);
f.add(panelleft);
f.add(panelright);
}
public static void main(String[] args) {
SNGUI StudyNotes = new SNGUI();
}
}

Why does Java pack does not size frame properly when textarea is used with other components?

I am creating a GUI using GridLayout to arrange multiple panels that are using FlowLayout. I am using pack to determine the size of the frame. If I have only a TextArea then it sizes correctly. If I have only other components it sizes correctly. But if I use both p1 and p2 in the code below the panel with the buttons does not size properly. The test code I am using is below. If I use only p1 or p2 it sizes properly, but not with both: Here is the image I am getting. I don't want all that extra space between the buttons and the textarea.
If I do textarea alone it sizes properly.:
public class GUIPractice extends JFrame
{
//declare GUI objects
JPanel panel;
JPanel p1, p2;
JButton btnAdd, btnShow;
JScrollPane js;
JTextArea taOutput;
//constructor
public GUIPractice()
{
//give frame a title
setTitle("GUI Practice");
panel =new JPanel(new GridLayout(0, 1));
btnAdd = new JButton("Add");
btnShow = new JButton("Show");
taOutput = new JTextArea(10, 20);
js = new JScrollPane(taOutput, JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED,
JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
p1 = new JPanel();
p1.add(btnAdd);
p1.add(btnShow);
p2 = new JPanel();
p2.add(js);
panel.add(p1);
panel.add(p2);
//add the panel to the frame
add(panel);
}
public static void main(String[] args)
{
GUIPractice frame = new GUIPractice();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setVisible(true);
}
}

It sizes correctly. The GridLayout means that all cells will be the same size. Since the text area is bigger than the buttons, you see extra space in the panel containing the buttons.
I would suggest you just use the default BorderLayout of the frame.
There is no need for your "panel" using the GridLayout.
You just use:
add(p1, BorderLayout.PAGE_START);
add(p2, BorderLayout.CENTER);
Now the p1 and p2 will be the proper height.
Also, there really is no need for "p2". You can just add the scroll pane directly to the frame.

Achieving a gui similiar to the picture?

My plan is to get a similiar output, but for some reason, I am only getting the south panel...
My logic is to have 1 Main panel with North Center South.
In the North I will puth the Jlabel and Textfield and align it to the right.
In the Center I wil leave it empty
In the South I will Add a BoxLayout y-axis in the first row another panel with centered boxlayout
Another BoxLayout in the second row of the South BoxLayour row, I will add another Boxlayout and align it to the left.
Here is my code:
public static void main(String args[]) {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
JFrame frame = new JFrame();
frame.setSize(new Dimension(500,600));
JPanel MainPanel = new JPanel();
frame.add(MainPanel);
JPanel NorthPanel = new JPanel(); //upper panel to add boxx layout and inside it 2 panls
JPanel ToPanel = new JPanel(); //inside north
JPanel SubjectPanel = new JPanel(); //inside north
NorthPanel.setLayout(new BoxLayout(NorthPanel, BoxLayout.Y_AXIS));
MainPanel.add(NorthPanel, BorderLayout.NORTH);
JLabel SubjectLabel = new JLabel("Subject"); SubjectLabel.setAlignmentX(Component.RIGHT_ALIGNMENT);
JTextField SubjectTextField = new JTextField(20); SubjectTextField.setAlignmentX(Component.RIGHT_ALIGNMENT);
JLabel ToLabel = new JLabel("To"); ToLabel.setAlignmentX(Component.RIGHT_ALIGNMENT);
JTextField ToTextField = new JTextField(20); ToTextField.setAlignmentX(Component.RIGHT_ALIGNMENT);
ToPanel.add(ToLabel);
ToPanel.add(ToTextField);
ToPanel.add(SubjectLabel);
ToPanel.add(SubjectTextField);
NorthPanel.add(ToPanel);
JPanel CenterPanel = new JPanel(); //Center panel blank
MainPanel.add(CenterPanel, BorderLayout.CENTER);
///
JPanel SouthPanel = new JPanel();
NorthPanel.setLayout(new BoxLayout(NorthPanel, BoxLayout.Y_AXIS));
JPanel FontPanels = new JPanel();
FontPanels.setLayout(new BoxLayout(FontPanels, BoxLayout.PAGE_AXIS));
FontPanels.add(new JButton("Bold"));
FontPanels.add(new JButton("Italic"));
FontPanels.add(new JButton("Underlined"));
FontPanels.add(new JButton("Undo"));
FontPanels.add(new JButton("Redo"));
FontPanels.setAlignmentX(Component.CENTER_ALIGNMENT);
JPanel OptionPanel = new JPanel();
OptionPanel.setLayout(new BoxLayout(OptionPanel, BoxLayout.PAGE_AXIS));
FontPanels.setLayout(new BoxLayout(FontPanels, BoxLayout.PAGE_AXIS));
OptionPanel.add(new JButton("Send"));
OptionPanel.setAlignmentX(Component.CENTER_ALIGNMENT);
SouthPanel.add(FontPanels);
SouthPanel.add(OptionPanel);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
});
}

You haven't added anything to the JFrame - so naturally it is displaying a blank JFrame.
For each component to appear, you'll need to do frame.add(component);
I leave the layout manager of the frame up to you.

Java GUI Logic - Not understanding adding to JFrame

I have a pretty straight forward question. Can some please please explain to me why the following JFrame is not showing Hello (100,100 pixels on the left side of the screen and World (100,100 pixels) on the right side of the screen since I am using border layout.
I created a JFrame
Assigned it a layout of borderlayout
Created 2 panels with 2 labels and assigned the panels to be aligned left and right.
added the panels to the JFrame
Displayed the JFrame
What am I missing?
JFrame frame = new JFrame("FrameDemo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(600, 500);
frame.setLayout(new BorderLayout());
frame.setVisible(true);
JPanel panel1 = new JPanel();
panel1.setPreferredSize(new Dimension(100,100));
panel1.setBackground(Color.BLUE);
JLabel label1 = new JLabel("Hello");
label1.setBackground(Color.YELLOW);
label1.setForeground(Color.WHITE);
panel1.add(label1,BorderLayout.LINE_START);
frame.add(panel1);
JPanel panel2 = new JPanel();
panel2.setPreferredSize(new Dimension(100,100));
panel2.setBackground(Color.RED);
JLabel label2 = new JLabel("World");
label2.setBackground(Color.CYAN);
label2.setForeground(Color.WHITE);
panel2.add(label2,BorderLayout.LINE_END);
frame.add(panel2);

You are setting the Layout-Constraints on the wrong panel.
Instead of panel2.add(label2,BorderLayout.LINE_END); it should be panel2.add(label2) and instead of frame.add(panel2); it should be frame.add(panel2, BorderLayout.LINE_END);.
Same for panel1.

How to center a component on a row containing multiple components with MiGLayout

I started using MiGLayout about a month and half ago and everything is simple and works great. There's only one issue I still have that I haven't been able to fix.
Let's say I want to have a row that has two buttons on the right-most side and a centered title, the title doesn't actually get centered when I do it this way:
("this" is a JPanel)
this.add(labelTitle, "split, span, center");
this.add(closeButton, "east");
this.add(mainMenuButton, "east");
What happens is that "labelTitle" is centered in the remaining space available after the buttons are placed, but I actually want it to be centered relative to the whole JPanel, not just the remaining space.
What parameters could I use to get the desired effect? I know I could use absolute positioning, but I don't want to do that because it defeats the purpose of using MiGLayout in the first place in my case.

Can it be something like this you are looking for?
Cheers!
public static void main(String[] args)
{
JFrame frame = new JFrame();
JPanel panel = new JPanel(new MigLayout("debug"));
panel.add(new JLabel("Label Title"), "x2 min(b1.x - unrel, (container.w+pref)/2)");
panel.add(new JButton("Close Button"), "id b1, pushx, alignx right");
panel.add(new JButton("Main Menu Button"), "alignx right");
frame.add(panel);
frame.setSize(800, 200);
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
frame.setVisible(true);
}

You can use the JXLayer and put the buttons in the glasspane.
JButton closeButton = new JButton("Close");
JButton mainMenuButton = new JButton("Menu");
JLabel labelTitle = new JLabel("Application");
JPanel panel = new JPanel();
panel.setLayout(new MigLayout(new LC().fillX()));
panel.add(labelTitle, new CC().alignX("center").spanX());
JPanel buttonPanel = new JPanel();
buttonPanel.setLayout(new MigLayout(new LC().fillX()));
buttonPanel.add(closeButton, new CC().alignX("right").split());
buttonPanel.add(mainMenuButton, new CC().alignX("right"));
buttonPanel.setOpaque(false);
JXLayer<JPanel> mainPanel = new JXLayer<JPanel>();
mainPanel.setView(panel);
mainPanel.setGlassPane(buttonPanel);
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setContentPane(mainPanel);
frame.setSize(400, 600);
frame.setVisible(true);

When creating your JPanel, use the following MigLayout initializer:
new MigLayout("","[]push[center]push[]","")
If you don't know about constraints, check here: MigLayout Whitepaper
This is assuming you don't have anything else in this JPanel...