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MVC in Java - Static controller?

I have a number of different organisations, each of which is an instance of the Organisation class. This contains getters and setters for instance variables, the setters contain validation where appropriate. It also has a few other odds and ends - overwritten toString(), equals() and hashCode() for example.
I have OrganisationView extends JFrame which accepts an Organisation and displays it in the GUI, and includes listeners for the various functions.
I understand from this question how this should all fit together and work with OrganisationController. What I'm not clear on is how many, if any, instances of OrganisationController I need. Is it one per organisation, and storing the organisation it refers to as an instance variable? Because it seems easier just to declare OrganisationController as static and call its methods directly from OrganisationView giving OrganisationView a method something like:
private boolean deleteButtonPressed(){
return OrganisationController.deleteOrganisation(this.organisationDisplayed)
}
(and perhaps some other business logic, but that's by the by)
OrganisationView, by the way, is called each time that particular display is needed, and is passed the organisation to show.
My question is: If it is better to have a separate instance of OrganisationController for each Organisation then why? It seems like an unnecessary amount of objects differing only in one instance variable. Or are static controllers acceptable?

I would not make it static. Use a singular controller and separate your views into directories. Then you can organized each part accordingly. You don't want to statically call the controller from the view. You want each person who logs in to have their own instance. Its simply a matter of separating out your views, models etc into separate folders and directories. I'm actually working on a project right now where I do this. I prepend each section with a keyword so as to keep it separate.

You can use the Singleton pattern to make sure that you only create one Controller && also access your controller in a static way.
I suggest you go for the enum implementation of Singleton which would be something like this
public enum OrganisationController{
INSTANCE;
// you can have fields
private final example;
// and also methods
public boolean deleteOrganisation(Organization org){
// do whatever here
}
}
And you can invoke methods in a static-looking way
OrganisationController.INSTANCE.deleteOrganization(org);

Is there a point to having a class with all non-static methods but no non-static fields? (or all static fields and methods along with a constructor)

I am looking at other peoples' code.
I see a class with no non-static fields but in which most of the methods are non-static, requiring you to make an object to access methods that effectively operate statically.
Is there a possible reason for this, that I am just not understanding?
EDIT
Someone asked for examples. Here is some more info.
For instance there is a file manager class. The only fields are static and are Comparators. There are some methods to do things like sort files in a list, count files, copy files, move files to an archive folder, delete files older than a certain time, or create files (basically take a base name as string, and return a File with given base name and date/time tacked on the end.)
9 non-static methods
5 static methods
I don't see a particular rhyme reason for the ones that are static vs non.
One particularly odd thing is that there are two methods for removing files. One that removes a file no matter what, and one that only removes it if it is empty. The former is a static method while the latter is not. They contain the same exact code except the later first checks if the file.length is 0.
Another odd one is a class that does encryption - all fields and methods are static but it has a constructor that does nothing. And an init() method that checks if a static variable contains an object of itself and if not instantiates an object of itself into that field that is then never actually used. (It seems this is done with a lot of classes - init methods that check for an object of itself in a static variable and if not instantiate itself)
private static File keyfile;
private static String KEYFILE = "enc.key";
private static Scrambler sc;
It has methods to encrypt and decrypt and some methods for dealing with key and file.
Does this make sense to anyone? Am I just not understanding the purpose for this stuff? Or does it seem weird?

Objects don't have to have state. It's a legitimate use case to create an instance of a class with only behaviour.
Why bother to create an instance ? So you can create one and pass it around e.g. imagine some form of calculator which adheres to a particular interface but each instance performs a calculation differently. Different implements of the interface would perform calculations differently.
I quite often create classes with non-static methods and no members. It allows me to encapsulate behaviour, and I can often add members later as the implementation may demand in the future (including non-functionality related stuff such as instrumentation) I don't normally make these methods static since that restricts my future flexibility.

You can certainly do it that way. You should look carefully at what the instance methods are doing. It's perfectly okay if they're all operating only on parameters passed in and static final static class constants.
If that's the case, it's possible to make all those methods static. That's just a choice. I don't know how the original developers would justify either one. Maybe you should ask them.

Let me rephrase this question a bit,
Even though methods are non-static why would one declare fields as static?
I have taken below quoting from Java Docs,
Sometimes, you want to have variables that are common to all objects. This is
accomplished with the static modifier. Fields that have the static modifier in their declaration are called static fields or class variables. They are associated with the class, rather than with any object. Every instance of the class shares a class variable, which is in one fixed location in memory. Any object can change the value of a class variable, but class variables can also be manipulated without creating an instance of the class.
For example, suppose you want to create a number of Bicycle objects and assign each a serial number, beginning with 1 for the first object. This ID number is unique to each object and is therefore an instance variable. At the same time, you need a field to keep track of how many Bicycle objects have been created so that you know what ID to assign to the next one. Such a field is not related to any individual object, but to the class as a whole.
For Bicycle example, kindly refer the Java Docs.

Making all methods non-static allows you to override them. This makes it a lot easier to use this class in testing, because instead of the actual implementation you can use a mock that behaves as you want it for the tests. Static methods are, in my book, a code smell and should be avoided unless there's a good reason (e.g. quite trivial utility methods).
Also, at some point in the future you might want to change the behaviour of the methods in some situation, e.g. in the form of a strategy.
In the case of your encryption class, you might want to hand your class an instance of the encryption class to handle encrypting/decrypting, but be able to configure the details in some other place. That would allow you to change the algorithm and much more easily test your own code without also having to test the encryption.

When to make instance variables private?

I'm trying to understand the usage for getter/setter methods in a class. Let's say we have a class called A with some public instance variables followed by a constructor with parameters where arguments were passed from another class(main) to it. Inside the constructor we let those instance variables equal what was passed.
Now if this class were to be used by another programmer, nothing would stop them from directly accessing/changing the instance variables to something that isn't valid. By making the instance variables private we can eliminate access to those variables. However if we wanted to have those instance variables updated/changed indirectly or under some specific condition or perhaps just letting the person have access to the instance variable, we would create a getter/setter pair for this purpose.
Benefits?:
1.Change instance variable only under certain valid reasons under the set() method
2.So that we can show what the instance variable actually is without giving the programmer who is using this class the ability to change it.
Is this a correct interpretation?

Encapsulation – refers to keeping all the related members (variables and methods) together in an object. Specifying
member variables as private can hide the variables and methods. Objects should hide their inner workings from the
outside view. Good encapsulation improves code modularity by preventing objects interacting with each other in
an unexpected way, which in turn makes future development and refactoring efforts easy.
Being able to encapsulate members of a class is important for security and integrity. We can protect variables from
unacceptable values. The sample code above describes how encapsulation can be used to protect the MyMarks object
from having negative values. Any modification to member variable vmarks can only be carried out through the setter
method setMarks(int mark). This prevents the object MyMarks from having any negative values by throwing an
exception.

Your interpretation is correct. Also (off the top of my head):
It allows the implementation of the class to change (eg if you wish to remove the field and replace it) without forcing consumers to interact with your class any differently.
It allows AOP frameworks to intercept calls to your get / set method.
You can specify permissions via annotations for access to methods.

Yes, your interpretation is correct. But it's because limits of language. For instance in python you don't need write everytime getter or setter, because you can override behavior of member variables. For example:
class MyClass:
def __init__(self, myproperty):
self.myproperty = myproperty
And if everybody use it in way like:
print(new MyClass("test").myproperty)
you can still change behavior of you getter:
class MyClass:
def __init__(self, myproperty):
self._myproperty = myproperty
#property
def myproperty(self):
return self._myproperty + " changed behavior"
or even of setter without touch code what use you class:
#myproperty.setter
def myproperty(self, myproperty):
if len(myporperty) > 0:
self._myproperty = myproperty
See property reference for better example.

if an instance variable is to be used only by methods defined with in its class, then it should be made it as private.If an instance variable must be within certain bounds, then it should be private and made available only through accessor methods[getter as well as Setter] Methods.

How would i access Object properties an object method?

What is the "correct" way to access an object's properties from within an object method that is not a getter/setter method?

Getter/Setter is the recommended way of accessing properties of an object. Otherwise you to have to use public properties, but public properties are not recommended.

If a classes' properties don't have getters and they are not visible (e.g. not public), that means that the class is designed so that you can't access them. In that case, there is no proper way to access them.
Flipping this around, if you are designing a class and you intend that other classes can access its attributes, you ought to provide getters. You could alternatively declare the attributes to be public, protected or package private, but that makes your abstraction leaky and has a number of undesirable consequences.
If you are asking how one of an object's methods should access its own attributes, the simple answer is whichever way is most convenient. If the class has getters, you could call them. Alternatively, you could just access the attributes directly. The problems of leaky abstraction don't apply in this case because the method accessing the state is inside the abstraction boundary.

This is mostly a matter of preference.
I personally prefer not to use the getters and setters in my object. This increases readability, allows me to change my getters and settings to return copies (of lists mostly) without it changing my own object. If you do something special in your getter then you can make a helper method that is used by both your getter and your other functions. This will go wrong if your classes get too large though (so don't make large classes). I don't like how using a getter setter hides the side effects inside the object (unlike for external users, they should be hidden from any side effects inside the object), when you want to have the side effects, give the private method a clear name indiciting it has them.

First off I'll answer the question as is:
What is the "correct" way to access an object's properties from within an object method that is not a getter/setter method?
When you are within an object, you can reference the properties directly where the method is part of the object. For example:
public class testClass() {
public int x;
private someMethod() {
x = 4;
}
}
To answer the comment:
I think the question can be reformulated: Should I use getters and setters when implementing my object methods? Or should I access member variables directly?
You should always hide the internal data and other implementation details within a class as much as possible; seperating the API from the implementation (a.k.a encapsulation). Encapsulation decouples the modules thereby allowing them to be developed, tested and modified in isolation.
Generally, you should use the lowest access modifier possible (e.g. private, protected, package-private) whilst maintaining functionality for the application you're writing. The benefits of designing and devloping this way is that you can change implementation details without breaking code that uses the modules. If you make everything public, and other people are using your classes, you are forced to support it forever maintaining compatibility - or until they change their implementation that is using your modules.
Instance fields should never be public as you give up the ability to limit the values that can be stored in the field, and if it is a mutable object, you open your object up for misuse (see here). It is important to note too that classes with public mutable fields are not thread-safe. It is also important to note that instance fields that are declared public static final but are mutable objects can also be modified and can be a security risk.
Basically, in public classes - always use accessor methods, not public fields. It allows you to protect your mutable objects from modification outside of the class (be it intentionally or unintentionally) and allows you to change implementation detail later without harming your clients.

Stuck on Object scope in Java

I'm working my way through an exercise to understand Java, and basically I need to merge the functionality of two classes into one app.
I'm stuck on one area though - the referencing of objects across classes.
What I have done is set up a gui in one class (test1), and this has a textfield in ie.
chatLine = new JTextField();
in another class(test2), I was planning on leaving all the functionality in there and referencing the various gui elements set up in test1 - like this test1.chatLine
I understand this level of referencing, I tested this by setting up a test method in the test2 class
public static void testpass() {
test1.testfield.setText("hello");
}
I'm trying to understand how to implement the more complex functionality in test2 class though, specifically this existing code;
test1.chatLine.addActionListener(new ActionAdapter() {
public void actionPerformed(ActionEvent e) {
String s = Game.chatLine.getText();
if (!s.equals("")) {
appendToChatBox("OUTGOING: " + s + "\n");
Game.chatLine.selectAll();
// Send the string
sendString(s);
}
}
});
This is the bit I'm stuck on, if I should be able to do this - as it's failing on the compile, can I add the actionadapter stuff to the gui element thats sat in test1, but do this from test2 - I'm wondering if I'm trying to do something that's not possible.
Hope this makes sense, I'm pretty confused over this - I'm trying to understand how the scope and referencing works.
Ideally what i'm trying to achieve is one class that has all the main stuff in, the gui etc, then all the related functionality in the other class, and target the first class's gui elements with the results etc.
Any thoughts greatly appreciated.

If you can access chatLine in the first place, you can call its (public) methods, including addActionListener. To access chatLine directly, you need to make it public, and if you want to make it specific to the class (as opposed to a different chatLine for each instance of the class), it needs to be static.
Note, however, that it's often desirable to not make variables public. An important reason for having classes and objects in the first place is encapsulation. You might consider hiding the implementation inside the classes by making it private and only providing higher level public methods to access what is needed, e.g. do not expose the "raw" JTextField but rather expose the functionality you use it to provide.

I'm not clear on whether chatLine is a local variable, an instance variable, or a static variable. Any of these things could be the source of your compile error, which you didn't specify -- what's the error?
If it's an instance or static variable, it can be made visible from anywhere by making it public. This doesn't mean that's a good idea.
At least, it should be private and exposed via a getChatLine() method.
Even then, there's some question about whether this design is the right one, but at least you'd be doing it right at a compiler level and basic data encapsulation level.

Generally speaking everything in Java is referenced but primitive types.
The so called visibility of objects is another matter:
public scoped members are visible
to all
'Package Friendly' members (those
that have no scope explicitly
mentioned) are visible to all abjects
belonging to the same package
protected scoped members are both
'Package Friendly' and visible to all
inheriting class objects
Finally, private scoped members are
visible only to the object itself
[Objects from the same class can view
each other's private members (as far
as I can recall)]
Now,
an inner static class can access its
enclosing class's static members.
A 'normal' inner class (without the
static modifier) can access its
enclosing class's static members
and enclosing object's instance
members - that goes as well to
anonymous inner class.
Finally any chain of method/field calls as below is valid (but ugly) as long as no part of the chain 'references' a null:
myObj.getThatObject().somePublicField.doSomthing().activate().someOtherPublicField
One recommendation though is not to declare members as public...