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Is it possible to find event fire chain in java?

I wanted to know do events have a priority in being fired or they are fired in the order they were registered?
For example I have a table and has two events on it,SelectionChanged and MouseClick,which one fires first if I click on a row?

See the class EventQueue. This class has all what you need, including the origin event (mouse or key event) for your selection event.

if the order of firing the events is important for You, just set up a chain of listeners, ie Listener one will notify listener two etc, so you could handle the order.
Also check this for more information:
Another question

personally, I think Observer pattern is usefully for your,it's deserved.

Key press events for GXT FileUploadField

GXT 3.x only.
It is becoming apparent to me that Sencha had deliberately designed FileUploadField to shunt off all key press events from ever being detected.
I tried to intercept onBrowserEvent(Event) and could not detect any key press events which I would have generated by keypresses while having focus on the FileUploadField component.
Where is the key-press event shunt?
I could not find any keypress handler insertion methods.
I wish to allow triggering the file upload by either press on the space-bar or enter key.
Short of rewriting a whole new component from scratch, could someone advise me what I could do to achieve my goal of a keyboard activated file upload?

onBrowserEvent won't recieve any events unless you sink them - did you make sure to call sinkEvents? How are you adding handlers? If you use addDomHandler, it will sink them for you, but addHandler either assumes that they are not dom events, or that you already called sinkEvents. Without sinking an event, the browser doesn't know to pass that event on to a GWT widget. If all events were sunk automatically, then every time you moved the mouse across the page you would see a firestorm of events as mousemove fired for every widget you passed, and all of its parents.
If you override onBrowserEvent, then you are building the method that describes how to handle the actual event that comes from the browser - that is where the com.google.gwt.user.client.DOM class wires into the Widget to give it events. Short of making that method final, there is no way to prevent you, the widget user, from getting those events as long as the browser is generating them and passing them through the event listener.
Even if onBrowserEvent has been overridden and made final, you can still get access to many events by creating a NativePreviewHandler and checking where the event is occurring. This gets you in to the event before it even goes to the widget itself - there you can call NativePreviewEvent.cancel() to prevent it from happening on the widget itself, or you can handle it early in the handler.

GWT. How to handle two similar actions with one event?

I've encountered next problem. I've got list of products and each product has button to open its QuickLook PopUp. I've created special event for this button, registered it in EventBus and trigger them. Everything seems good, but when I click one button, popup is shown not just for this item, but for all items, that are in list (I mean numbers of that "show"). This happens cause I have one Event-class for all these buttons, but can I somehow separate them one from another?
I just want to set some ID or something like that to every button and check this condition while triggering or (this would be even better) trigger only event, that I really need.

You don't need an EventBus for this. You can create a simple ClickHandler and attach it to your buttons. When you create a ClickHandler, you pass a product ID (or whatever you use to differentiate your products) to a method that shows your popup.

You can add productId to your Custom Event as a property. Event handler will check it and show only required product info.

How can I force an event listener to execute last in java?

I have a JTextPane that has a DocumentListener waiting for changes to the underlying HTML document. When the content changes, the event uses JTextPane.scrollToReference to move the view to a certain reference anchor. The problem is that the underlying View in the JTextPane is also listening to the document changes, and doesn't update until after my listener executes, which causes an exception. Is there any way I can force my DocumentListener to execute after any other event listeners for that particular event? Or is there some way I can wait for the view to be updated before executing my code?

First try to use SwingUtilities.invokeLater() for the listener that has to be executed as last. If that doesn't work, build your own priority queue.

Document is model fro JTextComponents, then not good idea put there two or more Listeners wrote changes to the Document,
all event should be done if model invoke all implemented event to the view, then only if are all events done in the view, then is possible moving with JViewport
no idea whats Listener you are implemented, but DocumentListener (e.g.) with FocusListener (e.i.) can creating endless loop with nice exception from RepaintManager
remove Listener that generating exceptions, add Listener if is really required, remove uselles Listeners immediatelly,
Swing quite no guarentee ordering of Listeners, nor events from multiplayed Listeners betweens model_to_view and vice versa
you can testing if Listeners firing events subsequently or gradually by pushing of required event from Swing Action (delayed from Swing Timer) or for asynchronous Listeners (freezed) by Thread.sleep(int)

I wound up having to extend the Viewport and JScrollPane classes to accomplish this. I exposed a listener for the viewport's change event and added my logic in there (which ensured it was the last code executed in the rendering chain).

Can we tell if the mouse actually clicked on a checkbox in Java?

Here is the scenario. I have an swing applet with tons of checkboxes. some of them are disabled/unchecked when checking another. Each ItemStateChange() event executes a method to parse the entire form for changes. Is there a way to tell if an ItemStateChange() event was triggered due to a mouse click or from a setSelected() call?
The ItemStateChange() for each checkbox has the standard parameter java.awt.event.ItemEvent evt
I'd like to only call the processOrder() method once when a box is clicked. Right now it fires for each change thats made, regardless of whether the change happened from setSelected(). Sometimes there are 10+ parseForm(); calls from a single click.

You can't tell whether the source of the event is a mouse click or a setSelected call from the ItemEvent.
It sounds like you have a loop in your check box logic. You might want to add a controller that handles the events and sets each checkbox yet ignores events that occur due to calling setSelected on other check boxes.

Is there a way to tell if an ItemStateChange() event was triggered due to a mouse click or from a setSelected() call?
If your application manually invokes the setSelected() method then you can use code like:
checkBox.removeItemListener(...);
checkBox.setSelected(...);
checkBox.addItemListener(...);

If you are able to change to use a MouseListener instead of an ItemListener and respond to the mouseClicked() event you will only receive the events for the checkbox selected by the user.