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What's the right way to go from one form to another?

I am doing a school java project using the NetBeans IDE. It includes some basic database manipulations. We were taught at school to use the following for linking one form to another:
new <form_name>().setVisible(true)
But this seem to slow down the whole application and there is a small lag for going from one form to another. I heard that using JDialog boxes is a solution to this problem.
So what's the right way to do it?

Better to not swap in and out of different JFrames. How many professional applications such as word processors do you use that do this that throw different windows at the user? Better to use one main JFrame and swap views (usually JPanels) in it via a CardLayout and occasionally show a dependent Window as a dialog when needed, especially when you need to get information in a modal way.

some basic database manipulations. .. But this seem to slow down the whole application
Don't block the EDT (Event Dispatch Thread) - the GUI will 'freeze' when that happens. Instead of calling Thread.sleep(n) implement a Swing Timer for repeating tasks or a SwingWorker for long running tasks. See Concurrency in Swing for more details.
(But also see #Hovercraft's advice re. CardLayout..)

Java Applet fail / disappear when another frame is reloaded in IE10

Does anyone face this problem?
Applet disappear when another frame is reloaded in IE10.
I found a related bug report in Java bug Database
http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=7193503
Any other solutions beside trigger repaint()?
By the way, how to vote the bug in Java Bug Database?

Any other solutions beside trigger repaint()?
3 posibilities jump to mind.
Launch the applet free-floating using Java Web Start.
Don't use frames.
Use an earlier version of IE, or a different UA.
By the way, how to vote the bug in Java Bug Database?
Step one is to join the OTN. Note that OTN members have complained about not being able to access the bug DB.

I have tried to trigger repaint() which still cannot solve the problem.
I think the components positions in applet are wrong after the frame is reloaded.
The workaround is resize the window by Javascript call.

Eclipse - showing full call stack (like when it hits breakpoint in debugger) without putting in breakpoints?

I'm working with a legacy Java app that is new to me so one way to figure out how it works and find things easier, I have thought would be to be able to get the full stack trace after I perform actions, so as to be able to see which classes are being used based on a particular UI action. I had thought this was possible in the debugger but it seems that it only works if I insert a breakpoint and in this case part of the purpose of this is so that I don't have to know what's being called to be able to insert the breakpoint first (as this would help tell me that).
I apologize if this is a basic question, I have searched on this but I'm not finding the correct answer.

This doesn't directly answer your question, but maybe it will solve your problem better. Take a look at BTrace. It lets you instrument a running Java app and insert some basic code of your own. You could, for instance, have it write out entire method call chains to help you find your way through the app. It's somewhat similar to AspectJ, but with an entirely different purpose and requiring no change in the project source:
"BTrace is a safe, dynamic tracing tool for Java. BTrace works by dynamically (bytecode) instrumenting classes of a running Java program. BTrace inserts tracing actions into the classes of a running Java program and hotswaps the traced program classes."

A few suggestions:
Some profilers will allow you to walk from any particular method up (and sometimes down) to see what's calling and being called. I've found this surprising informative about flow, even in apps I thought I knew well.
For understanding the mainline flow, I don't think there's a better substitute for working interactively with a debugger. It will lead you into learning other important things. Not what you wanted to hear, I know. This presumes that you can rapidly restart the app when you miss a key off-ramp.
Reverse-designing large legacy apps is the one place where I use UML fairly regularly. There's too much to keep in my head to form a good big picture. If you have a UML tool that will do reverse-engineering, load it up with the app, then probably prune down hard on the classes you don't care about, because they are trivial or obvious. Arrange the diagrams in a way that helps you understand. I've used Together, Magic Draw, and Visual Paradigm in this way. Together worked the best - but it was a decade ago.

When you are in the debugger perspective, you will see a view showing the launched processes. In that view you can tell it to pause all threads of a process. Once stopped, you will be able to browse through threads to see what they are all doing. To try to catch what a particular action is doing, you would have to start the action and then quickly pause all threads.

You could always run the application with the VM arg of -verbose:class. You could then watch the console output and see what classes the VM is loading when you perform a particular action. This could possibly give you a starting place for where to place breakpoints. This won't always work depending on the scenario, but may be helpful.

Another trick you can use is to figure what classes you know that have to be involved in the code path you are trying to trap. For instance, you mentioned that it's a Java EE web app and therefore the action is likely some kind of a servlet interaction (at some level). I don't have the API in front of me, but you can place a breakpoint on the method in the response object where the output stream is retrieved. Once that breaks, you will know the code that's trying to service the request.

You can always see where a method is called by clicking "Open Call Hierarchy" from eclipse (left click on the selected method or CTRL+ALT+H ). Also, you always can inspect where a method/class is defined by clicking "Open Declaration" (left click on the selected method/class or F3).

Multiple Swing event-dispatch threads

I would like to create a new event-dispatch thread in Swing, and I'm having trouble finding any references online for how to do this. I have done this in .NET by creating a new thread and calling Application.run(...). Has anyone done this? Is it possible in Swing?
FYI the reason I am trying to do this is because I am writing an Eclipse plug-in, and I would like to pop up dialogs that are not modal to the IDE but that are modal (blocking) to my UI logic. I could accomplish this using non-modal dialogs and callbacks, but that requires the overhead of making my code multi-threaded. I'll revert to that if the former is not possible.

Yes, it's possible. I've have done such multiple EDT dispatch threads logic in Swing. However, net result was that it didn't work reliably.
(a) All JVMs don't work nicely with multiple EDT threads (synchronization problems in graphics rendering logic in native code and such, IBM JVM failed with multiple EDT threads, Sun JVM & Apple JVM did work)
(b) Swing rendering logic has few bugs causing that random rendering errors will occur (for example, http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6727829).
Anyway, doing this requires basically establishing two AppContexts, which each have their own EDT thread.

I'm a little confused by your question, because you mention Swing but then say you are writing an Eclipse plugin. Since the question is tagged Swing, I'll give a Swing answer (but posted as CW).
There is one event dispatch thread. There is always one event dispatch thread, unless there is none at all. You cannot create another one.
You can, however, change the ModalityType of your dialogs, or change the ModalExclusionType of a window. In this case, if you were writing this all yourself, you would set your top-level window's ModalExclusionType to APPLICATION_EXCLUDE.
But again, I don't see how this could help you, since Eclipse uses SWT instead of Swing.

I'm going to junk my last answer and start anew.
In SWT, you can create Shells (windows) or custom Dialogs that are modal just to the parent by passing the SWT.PRIMARY_MODAL style flag during creation.
Note that Dialog is an abstract class, so you'd have to create your own. It's probably just easier to use Shell.
Edit:
Why SWT? Because that's what Eclipse uses. See: Eclipse Platform Plug-in Developer Guide (zipped PDF) for more details. The most recent version is available in Eclipse's Help system (Help > Help Contents > Plug-in Development Environment Guide.)

Force a full Java applet refresh (AWT)

I have a Java Applet that uses AWT. In some (rare) circumstances, the platform does not refresh the screen properly. I can move or minimize/maximize the window and see that my applet refreshed properly. I am looking for code that will give me the fullest possible applet screen repaint, simulating the behaviour of a minimize/maximize.
I've tried calling various combinations of paint()/repaint()/invalidate()/update() on the parent containers and recursing on various children. However, no combination (that I've found) cleans up the framework bugs that I am encountering. I am looking for techniques to fully refresh the applet, even if they may cause some slight flickering, as I will be invoking this code only on the problematic platform.
In my tests, moving to Swing did not help resolve my problem.
By the way, this is a simplification of my previous (more complicated) post: Java Applet, AWT Refresh problem Mac OS X 10.4
Edit: Investigation in threading did not solve this problem. Marking best answer as the good one.

This happens all the time if you are not programming carefully in AWT/Swing.
First of all, you should do ALL work on the event thread. This means you can't do any of it in your main statement (or anything it calls directly). I know every Java GUI app ever invented violates this rule, but that's the rule.
For the most part, they used to say you could use a non-awt thread until the window was "Realized" (pack/setVisible), but Sun figured out that didn't always work.
Second, when you get an event on the AWT thread, be sure to return it quickly. Never sleep or execute a long operation.
Third, (and this is an extension of "First", if you get a callback that is NOT already on the AWT worker thread, be sure to put it on the AWT thread before doing anything with the GUI.
Generally, any event generated by an AWT component will be on the correct thread. Events generated by timers, manually created threads, or the one handed to main() are not.

The method to use for this kind of problem is repaint, as you've mentioned. It's possible you are seeing an issue with the JVM you are using. I'd recommend using different versions of the Sun JVM and even the MS VM for IE to see if this is a VM related problem - it may actually be unrelated to your code.
I haven't actually tried this before, but a creative way (ie. nasty hack) around this might be to execute javascript from the applet to call a DOM method to do a mock resize of the window or perhaps call focus on the body in an attempt to cause an external re-drawing of the canvas.

Not sure if this is related to what you've seen, but if you get up against the performance of the AWT Event Queue the java 2d + 3d world (graphics pipeline folks) will point into a threaded strategy and then you'll get into the dispose problem.
This discussion has been looking at designs employing the AWT Event Queue for graphics, as in using "repaint".
In the threaded approach, there is a shutdown problem.
Notes in java/awt/SequencedEvent for "dispose" point us to "AWT Threading Issues" and "Autoshutdown".
I'm thinking that this bit of info serves at least to focus the problem.

I was able to fix 99% of my AWT Applet redraw issues by switching to Swing. Swing seems to be more reliable on refreshing.
Earlier I had a lot of manual repaints() in my applet code, but with Swing these were removed and applet is now faster especially under Terminal Server / LTSP.
I placed critical stuff inside this:
public class VeryFastPanel extends JPanel {
/**
*
*/
private static final long serialVersionUID = 1L;
public void update(Graphics g) {
paint(g);
}
}

I found an issue that appears to be the same you are experiencing. After some tests, I discovered that this can be related to Aero and Intel Graphics adapters. In my case, the application stopped repainting only when used in notebooks without AC adapters, powered by batteries. If you disable some power saving features in Intel driver configuration (notably Intel 2D Display Technology in old driver releases) Java will repaint normally again.
In my case I found also ways to disable this option via registry. It's not documented, but it works.