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components are separated when they are suppose to be in succession vertically

I want the image and the title (JLabel) to both me centered and be at the top of the page but instead the image is at the top of the page and centered but the title is 3/4ths of the way down the page and centered.
GridBagConstraints c = new GridBagConstraints();
c.anchor = GridBagConstraints.NORTH;
c.insets = new Insets(10, 0, 0, 0);
c.weighty = 1;
c.gridy = 0;
panel.add(image,c);
c.gridy = 1;
panel.add(title, c);

c.weighty = 1;
c.gridy = 0;
panel.add(image,c);
c.gridy = 1;
panel.add(title, c);
You don't reset the "weighty" constraint so it is used for both components. Therefore, the "extra" space in the frame is allocated equally to each component. So you see the extra space between the two components.
Add a Border to each component and you will see the actual size of each component.
The solution is to assign set the "weighty" constraint to only the second component so the first component is displayed at its preferred size.
//c.weighty = 1;
c.gridy = 0;
panel.add(image,c);
c.gridy = 1;
c.weighty = 1;
panel.add(title, c);

GridBag Layout, positioning the pieces

What I want is the label and check box at the top left corner and the three buttons on the bottom right corner.
However, it doesn't appear the the anchors are working properly.
Result:
Code:
JPanel bottomPanel = new JPanel( new GridBagLayout() );
GridBagConstraints c = new GridBagConstraints();
c.gridx = 0;
c.gridy = 0;
c.insets = new Insets(0, 0, 0, 20);
c.anchor = GridBagConstraints.NORTHEAST;
bottomPanel.add(spinachLabel, c);
c = new GridBagConstraints();
c.gridx = 1;
c.gridy = 0;
c.anchor = GridBagConstraints.NORTHEAST;
bottomPanel.add(checkbox, c);
c = new GridBagConstraints();
c.gridx = 0;
c.gridy = 5;
c.weightx = 0.5;
c.insets = new Insets(0, 0, 0, 5);
c.anchor = GridBagConstraints.SOUTHWEST;
bottomPanel.add(applyButton, c);
c = new GridBagConstraints();
c.gridx = 1;
c.gridy = 5;
c.weightx = 0.5;
c.insets = new Insets(0, 0, 0, 5);
c.anchor = GridBagConstraints.SOUTHWEST;
bottomPanel.add(refreshButton, c);
c = new GridBagConstraints();
c.gridx = 2;
c.gridy = 5;
c.weightx = 0.5;
c.anchor = GridBagConstraints.SOUTHWEST;
bottomPanel.add(cancelButton, c);
return bottomPanel;

First, we need to clarify what GridBagConstraints.anchor does: It specifies the placement of a component within the GridBagLayout cell.
spinachLabel is being placed at gridx = 0. applyButton is also being placed at gridx = 0. Therefore, they are guaranteed to be placed in cells which are in the same column. Their respective anchor constraints can move their position within their cells, but cannot move the cells themselves.
Second, you have not set any weighty constraints. Whenever a container which uses a GridBagLayout is larger than the preferred sizes of its child components, it uses the GridBagLayout’s weight constraints to decide which cells will grow to take up that extra space. When there are no weight constraints at all, as is the case for the vertical dimension in your layout, GridBagLayout doesn’t give any of the cells that extra space, and instead centers them. That’s what you’re seeing: Since no cell has a weighty set, all the cells are vertically centered.
In summary, your components will never appear at the top and bottom, unless you set some positive weighty constraints.
This doesn’t seem like a good use of GridBagLayout. When you want to place components at the edges, BorderLayout is usually a better choice:
JCheckBox checkbox = new JCheckBox("Enable Spinach Study");
JButton applyButton = new JBUtton("Apply");
JButton refreshButton = new JBUtton("Refresh");
JButton cancelButton = new JBUtton("Cancel");
JComponent buttonPane = new JPanel(new FlowLayout(FlowLayout.TRAILING));
buttonPane.add(applyButton);
buttonPane.add(refreshButton);
buttonPane.add(cancelButton);
JPanel bottomPanel = new JPanel(new BorderLayout());
bottomPanel.add(checkbox, BorderLayout.PAGE_START);
bottomPanel.add(buttonPane, BorderLayout.PAGE_END);
(A JCheckBox should always have text, rather than being placed to the right of a label. That way, the user has a much larger mouse target, and your user interface is accessibility compatible.)

GridBagConstraints filling both VERTICAL & HORIZONTAL

How do I go about filling both the vertical and horizontal space available in the grid cell of interest?
For example:
JTextArea file1 = new JTextArea();
file1.setBorder(BorderFactory.createLineBorder(Color.black));
c = new GridBagConstraints();
c.gridx = 0;
c.gridy = 1;
c.weightx = 1.0 / ELEMENTS_IN_WIDTH;
c.weighty = 0.9;
c.insets = new Insets(PAD, PAD, PAD, PAD);
c.fill = GridBagConstraints.VERTICAL;
mainPanel.add(file1, c);
This fills the cell vertically but not horizontally.
Obviously adding c.fill = GridBagConstraints.HORIZONTAL after the VERTICAL value will only override the value of c.fill
OR'ing them like c.fill = GridBagConstraints.HORIZONTAL | GridBagConstraints.VERTICAL also doesn't do the trick.

You should use:
GridBagConstraints gridConst = new GridBagConstraints();
gridConst.fill = GridBagConstraints.BOTH;

I was to hasty and missed the obvious field of GridBagConstraints.BOTH. The issue is now resolved... sorry for the false bother.

Does GridBagLayout require placeholder panels for empty cells?

I made a simple GridBagLayout which adds buttons in the cells (0,0), (1,0), and (0,1).
JPanel panelMain = new JPanel(new GridBagLayout());
GridBagConstraints c = new GridBagConstraints();
c.gridx = 0;
c.gridy = 0;
panelMain.add(new JButton("0,0"),c);
c.gridx = 1;
c.gridy = 0;
panelMain.add(new JButton("1,0"),c);
c.gridx = 0;
c.gridy = 1;
panelMain.add(new JButton("0,1"),c);
I was happy to see the resultant UI:
I want to add a JButton in a cell that is not connected to the existing cells. I want it to be separated by an empty space. When I try this, the new JButton is lumped in next to the others. Here is the addition:
JPanel panelMain = new JPanel(new GridBagLayout());
GridBagConstraints c = new GridBagConstraints();
c.gridx = 0;
c.gridy = 0;
panelMain.add(new JButton("0,0"),c);
c.gridx = 1;
c.gridy = 0;
panelMain.add(new JButton("1,0"),c);
c.gridx = 0;
c.gridy = 1;
panelMain.add(new JButton("0,1"),c);
c.gridx = 3;
c.gridy = 0;
panelMain.add(new JButton("3,0"),c);
The output:
The JButton("3,0") is displaying at the cell (2,0). Do I need to use an empty JPanel as a place holder in the cell (2,0)? More importantly, why is this happening?

The layout does not know what should be the width to be left at 2,0 unless there is a component placed in the gridx = 2. By the time you complete the UI, if any component gets placed, it should look fine. For e.g.:
In other case you may add empty JPanel with background color matching to the background color of the container.

Do I need to use an empty JPanel as a place holder in the cell (2,0)?
You can use an "insets" grid bag constraint to give space between components. Read the Swing tutorial on How to Use GridBagLayout for more information on the inset constraint.
Or, if you want to have a place holder then you can use a Box.createHorizontalStrut(...) to easily specify the width.
More importantly, why is this happening?
Cells don't have a size unless there is a component in the cell. Each cell is independent of one another so what size would you expect cell (2,0) to be?

JTextArea in GridBagLayout stealing too much space

I have a GridBagLayout, and for some reason my JTextArea has decided that it doesn't want to listen to gridbag's ratio for with, and when create the panel which contains the layout my textbox grows till it takes up 1/2 of the screen. Heres some code:
tp = new JTabbedPane();
tp.setFont(Main.f);
//Adds tabs with several buttosn to my tabbed pane
for(Menu menu : FileManager.menus){
JPanel tmp = new JPanel();
int s = (int) Math.ceil(Math.sqrt(menu.products.size()));
tmp.setLayout(new GridLayout(s,s));
for(Product p : menu.products){//Act as
p.setFont(Main.f);
p.addActionListener(this);
tmp.add(p);
}
tp.addTab(menu.name,null,tmp,null);
}
receipt.setBorder(BorderFactory.createEtchedBorder());
//starting up with GridBag
setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.fill = GridBagConstraints.BOTH;
gbc.ipadx = 0;
gbc.ipady = 0;
//sets up and adds the JTabbedPane
gbc.gridx = 0;
gbc.gridy = 0;
gbc.gridwidth = 1;
gbc.gridheight = 1;
gbc.weightx = 0.8;
gbc.weighty = 0.8;
add(tp,gbc);
//sets up and adds receipt - The one that takes up half the screen
gbc.fill = GridBagConstraints.BOTH;
gbc.gridx = 1;
gbc.gridy = 0;
gbc.weightx = 0.2;
receipt.setEditable(false);
receipt.setText("Ticket number: 0\n" +
"Transaction number: 0\n");
receipt.setLineWrap(true);
add(receipt,gbc);
//sets up and adds a JPanel that has a bunch of buttons on it(Uses gridlayout)
gbc.fill = GridBagConstraints.BOTH;
gbc.gridx = 0;
gbc.gridy = 1;
gbc.gridwidth = 2;
gbc.gridheight = 1;
gbc.weightx = 1;
gbc.weighty = 0.2;
add(buttons,gbc);
buttons.setLayout(new GridLayout(1,8));
createButton(newtable);
createButton(remove);
for(JButton a : quicks)
createButton(a);
createButton(pay);
createButton(exit);
revalidate();
repaint();
When I change the TextArea to a blank JButton it doesn't take up much space at all. Basically the space is filled by the object on the right. How do I tell gridbag that I want my left object to span 4/5ths of the screen, and the right object to span the last 1/5th? In this version I attempt to do so using weighting, in my original version I attempted to do so using cells, so the left object was at gridx=0 gridwidth = 4, and the right object was gridx = 4 gridwidth = 1
Neither way worked. I am also open to alternate ideas(like better layouts, or a JTable?)
Thanks for your help,
Chase
What it's doing
Dimensions for what it should do

If you are not fixed on precisely 4/5 and 1/5 ratio, you can use BorderLayout and place buttons to the center and text area to the East.
Border layout will display the text area as wide as you supply - specify preferred size (width, you can set height to whatever number you want, border layout will ignore it). The rest of the space is then taken up by buttons panel.
You can learn more about border layout here: http://docs.oracle.com/javase/tutorial/uiswing/layout/border.html