Calling a method from a static method

hello all,
I'm calling a non-static method from a static method (from the main method). To overcome this i can make the method i am calling static but is there another way to get this to work without making the method that is being called static?
all replies welcome, thanks

When you call a non-static method, you are saying you are calling a method on an object. The object is an instance of the class in which the method is defined. It is a non-static method, because the instance holds data in it's instance variables that is needed to perform the method. Therefore to call this kind of method, you need to get (or create an instance of the class. Assuming the two methods are in the same class, you could do
public class Foo
     public static void main(String[] args)
            Foo f = new Foo();
            f.callNonStaticMethod();
}for instance.

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Calling non-static command from within static method

Hello,
I have a static method that reads bytes from serial port, and I want to set a jTextField from within this method. but I get error that says it is not possible to call non static method from a static one. How can it be solved?

ashkan.ekhtiari wrote:
No, MTTjTextField is the name of jTextFiled class instance.You haven't declared any such variable in the class you posted, not to mention that such a variable name violates standard code conventions.
This is and instance of that object actually. You haven't declared any such variable in the class you posted.
the problem is something else. No, it isn't, based on the information you have provided. If you want accurate guidance, don't post misleading information about your problem.
It can not be set from within static method.A question commonly asked on Java forums concerns an error message similar to the following:
non-static variable cannot be referenced from a static context
In Java, static means "something pertaining to an object class". Often, the term class is substituted for static, as in "class method" or "class variable." Non-static, on the other hand, means "something pertaining to an actual instance of an object. Similarly, the term instance is often substituted for non-static, as in "instance method" or "instance variable."
The error comes about because static members (methods, variables, classes, etc.) don't require an instance of the object to be accessed; they belong to the class. But a non-static member belongs to an instance -- an individual object. There's no way in a static context to know which instance's variable to use or method to call. Indeed, there may not be any instances at all! Thus, the compiler happily tells you that you can't access an instance member (non-static) from a class context (static).
Once you understand this concept, you can fix your own problem.
~

Pass an object from a static method

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I'm trying to pass a reference to an object from a static method, but I get an error when compiling.
Say for example I have this:
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how can I get a reference to obj2 then?Pay no attention to zdude's answer - it's nonsense.
You're confused about basic Java concepts. obj2 is a class, not an object. References point to objects, not classes. There is no obj2 object in the code you show, so you cannot have a reference to an obj2 object.
Maybe if you post some more code, we can get an idea of what you're trying to do. You might want to try the New to Java forum.

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Hi,
Is there any way to call view controller method from component controller method?
Thanks,

Hi Khandal.
You should not make you component controller dependent from a view controller.
But what you can do is to define an event in the component controller. The view
controller can register for this event.
In the stage where you currently want to call the view controller method just fire
the event. In the event handler method in the view controller you can call the
method then.
Why do you need to call a view controller method? Can you give more details
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writing the method as static method or not static
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Accessing a method from within another method

I am having trouble accessing a method from inside a method in the same class.
here is my code:
public String getAns(int ans){
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ranswer = number1 * number2;
if(answer != ranswer){
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Thank you in advance

next time use the correct code tags to post your code.
Think of your problem like this though.
You write
if( something )
then return some value;
else
then return some other value.
The returns end the method here, returning the value.
So, if the method ended at one of these 2 statements, how do you think it'll reach genQues(); ?
Hope this helps.

How to call a EJB method from Session bean method

Hi all,
I'm new to J2EE programming. I have a simple doubt .
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Calling stored procedure from session bean method

I have a situation like this :
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call the stored procedure
session bean method end
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Vimal

Hi Vimal,
Will the data that I am storing in tables from within
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Hi Raja,
Well it is not yet afternoon for me. In fact the work day just about started
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Access to Class information from a static method

There does not appear to be anyway to access the Class object from instead a static method.
e.g. How could I convert the following code so that it works ?
class test {
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System.out.println( getClass().getName() );

The idea was to have a static method that could be
used to make a lookup based on the classname. Being
able to access the class name would mean that I would
not have to reimplement for every subclass !!!!!Hmm.. what are you trying to look up? Some kind of class-specific constant information maybe?
In general your best bet is to define an abstract method in your parent class for return of the constant value, then define a specific method in each sub-class that overrides it, retrurning the appropriate value.
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Using some kind of lookup on the basis of class name is much clumsier, and more inclined to run time errors. Better to use the built in virtual methods table.
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ADF: Can i call javascript function from java clsss method in ADF?

Hi,
I want to call javascript function in Java class method, is it possible in ADF? , if yes then how?
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Regards,
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Static method or not static method

I have a simple class, ClassA, with no shared class variables, and has only one static method only:
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try {
//very time consuming I/O task
catach (Exceptions e) {
//try to resolve the problem
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2) If there are 20 threads call ClassA.doIO(args) at the same time, would the method be executed in parallel or queued?
Many thanks.
java9394

Using a static method makes this implementation as efficient as possible. Since the class has no instance variables, there is no benefit, to either making it non-static, or creating multiple instances. If you have 20 threads calling it, they will run concurrently. So, if you do not like this behavior, the method can be declared both static, and synchronized.

In JNI how to call Java methods from native language methods

I just build the example of java tutorial on
http://java.sun.com/docs/books/tutorial/native1.1/implementing/method.html
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Callbacks.c:2:parse error before '*'
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Hi all,
I need to call a dialog box from a method in the component controller. It would be helpful if u could post the code too.
Thanks,
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Hi Maksim,
this is the code i wrote:
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Calling a method from a static method

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