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What is the best way to display ASCII in a grid with panels using Java?

I don't have much experience in Java, but I am attempt to write a simple rogue-like game to familiarize myself with it, and I am just wondering how I would go about creating an interface like this:
Are there any obvious ways that you would go about something like this? Being new to Java, I really have no idea what the best method would be.
Sorry to be vague!
Thanks

There is no such (simple) component in the JDK - if you don't need color, a JTextArea can be used to display ASCII-Art (after setting a fixed-width font). You will need to take care not to run into characterset issues (if you don't stick to US-ASCII 7-bit).
Writing a component that handles color display (and maybe escape sequences, in essence emulates a console window) wouldn't be too hard, but if you just started with Java it may prove to be an unwelcome challenge.
You could also just write your game in Java and leave displaying the ASCII to the system console (your game would simple output to stdout).
Edit: Color ASCII could be acieved by converting your internal format to (simple) HTML and that HTML could be displayed using a JLabel. Its probably not the most elegant method, but it should be reasonably simple to implement (and with nowadays hardware speed should not be an issue with this approach either). This approach builds on the capability that you can just use JLabel.setText() and pass a string that starts with a HTML tag. The JLabel then interprets the whole text as HTML.

Check out Trystan's Ascii Panel, and his blog and tutorial on making a roguelike here.

Better late than never, right? You may want to check Zircon Project.

Code/text folding in SWING

I'm looking for a way to provide 'text folding' capabilities to a swing JTextArea or JTextPane
More specifically, I want to add a block of data in a text component and I want the component to display only some header line. Then the user can unfold the block by clicking some icon. This is just like the code folding feature in most IDE.
I've found ->some sample code<- after some thorough search, but the mechanisms used here are quite obscure to me and it stops working when I try to remove text from the document.
Maybe using XML as input could be a lead ?

This one how to add collapsible area
http://java-sl.com/collapse_area.html
This one how to represent XML
http://java-sl.com/xml_editor_kit.html

I would start by looking at the NetBeans API: http://bits.netbeans.org/dev/javadoc/org-netbeans-modules-editor-fold/overview-summary.html
If you were to do it yourself, you'd need to provide a Document implementation that makes the JTextComponent think that pieces are being added or removed, then attach click events that tell the document to update itself. A lot of work.
Visually, it may also be better to use JEditorPane, but that's probably more work.

How do i format a specific word/sentence inside jeditorpane?

I am not a java expert. Just learning as i go.. This is my way! I am now designing a IDE for C++ (just fun, not professional) . I have the project almost ready, now i want to add some text highlighting function to the IDE. For example i want the IDE to recognize a predefined set of words and color them green,red. How do i do it?

You could use HTML, but you probably would be better off using the TextAction methods for a JEditorPane.
Another alternative is the StyledDocument interface.
Added because of the comment: You can use the StyledEditorKit class to see implementations of TextAction.
Here's Oracle's tutorial on How to Use Editor Panes and Text Panes.

Ability to view text in each class

Recently, I program for the Android platform. I have a question about the text.
Is there any way to display the text without using the XML?
I also want the text to be able to show in each class.

If you're asking if you can replace the text of anything programatically, yes you can. Usually, you have a setText method you can use for that. I'd advise you to read the tutorial and the javadoc to know more about this.

Looking for an efficient Java Swing based console

I'm looking for a highly efficient Swing Java component which I can just plug into my application UI. I already tried using the classes within Swing such as JTextArea with no avail; they simply aren't high-performance enough and have any crippling drawbacks. Additionally, it'd be nice if it had standard console features such as scroll-lock, clear console, colours, and so on.
Edit: Forgot to say, this console will have a lot of debug information streaming into it, and it needs to be fully scrollable.
Cheers,
Chris

I fail to see what is wrong with using a JTextPane. It supports attributes which you can specify as each piece of text is added to the console. Clearing it is also obviously a no brainer. When added to a scroll pane it also supports scrolling.
You can add scroll locking by using Smart Scrolling.
Plus, it removes text too early and
No idea what that means as text is never removed unless you specifically remove it from the document.
doesn't allow the user to scroll while
input is being entered (afaik). The
effect is that you just see text
flashing while the number of rows
remains the same.
By default the text scrolls automatically as text is append to the document assuming the code is executed on the EDT. This scrolling can be controlled the the example provided in the link above.
Edit:
but I'd still like a library solution
I don't know of any
auto-colourise text coming from
different streams
The Message Console might give you some ideas.
(i.e., detect [error] prefix on a
line) and colourise lines based on
this)
This is easily done by adding a DocumentFilter to the Document of the text pane. You can add attributes as text is inserted into the Document.

Be sure that you read about the Event Dispatching Thread (EDT) in swing!
BTW: a simple search 'java swing console' will give you a lots of hints OR you could use/adapt the beanshell textfield which is a jtextfield too ...