non-static

What Cases Require Synchronized Method Access in Java?

In what cases is it necessary to synchronize access to instance members? I understand that access to static members of a class always needs to be synchronized- because they are shared across all object instances of the class. My question is when would I be incorrect if I do not synchronize instance members? for example if my class is...

What does "operator = must be a non-static member" mean? (C++)

I'm in the process of creating a double-linked list, and have overloaded the operator= to make on list equal another: template<class T> void operator=(const list<T>& lst) { clear(); copy(lst); return; } but I get this error when I try to compile: container_def.h(74) : error C2801: 'operator =' must be a non-static member ...

Static Web Service over non-static

Currently I have a web service (WCF) that exposes methods that are set to static. From a strictly memory/GC perspective, what is different in how the CLR and GC handle static versus non-static objects? ...

Modifying a non-static object from a static method.

Hi, I'll first tell you what I am trying to do, and then how I am trying to do it. If there is a better way please let me know. I am working with two forms - lets call them form_main and form_preferences When the form_preferences form is up, I want form_main to be disabled until a button (save button) on the form_preferences is clicke...

Static vs. non-static method 2

Possible Duplicate: Static vs. non-static method which one is better for a good design or are there any difference? or is it just up to the developer? class Foo { int x; void add(Foo* f1) //Method 1 { x += f1->x; } static void add(Foo* f1, Foo* 2) //Method 2 { f1->x = f1->x + f2->x; ...

Java Thread using static or non-static nested class

I've encountered a very strange problem. My program looks like this: class Outter{ class Inner extends Thread { public void run(){ // do something } } public void func() { new Inner().start(); // Thread.sleep() for a while to see if the above thread has fin...

static method with polymorphism in c++

hi, I have a weird issue using polymorphism. I have a base class that implements a static method. This method must be static for various reasons. The base class also has a pure virtual method run() that gets implemented by all the extended classes. I need to be able to call run() from the static class. The problem, of course, is that th...

java 1.4 :how to insert multiple records in a database with one single hit using executeBatch?

i am reading records data from a file(records count can be up to thousands ).Now i want to insert each record in to database.I want to insert all of records in one hit to reduce performance hit. If i use addBatch(String sqlQuery ) on statment object,my sql query should be static .but in my case query will be non static.Please tell me pos...

Triggering a non-static class from a static class?

I am writing a class library(API) in C#. The class is non-static and contains several public events. Is it possible to trigger those events from a static method in a separate class? For example... class nonStaticDLLCLASS { public event Event1; public CallStaticMethod() { StaticTestClass.GoStaticMethod(); } } class Stati...

calling non-static method in static method in Java

Hi, I'm getting an error when I try to call a non-static method in a static class. "Cannot make a static reference to the non-static method methodName() from the type playback" I can't make the method static as this gives me an error too. "This static method cannot hide the instance method from xInterface" Is there any way to get ro...

Non static members as default parameters in C++

I'm refactoring a large amount of code where I have to add an extra parameter to a number of functions, which will always have a value of a member of that object. Something like class MyClass { public: CMyObject A,B; void MyFunc(CMyObject &Object); // used to be void MyFunc(); }; Now, I'd actually like it to read class MyC...

Is there any way for a static method to access all of the non-static instances of a class?

This is probably a dumb question but I'm going to ask it anyways... I am programing in C#.NET. I have a class that contains a non-static, instance EventHandler. Is it possible to trigger that EventHandler for every instance of the class that exists from a static method?? I know this is a long shot! ...

Java method help

Ok, so I'm working on a project for a class I'm taking.. simple music library. Now I'm having some issues, the main issue is I'm getting "non-static method cannot be referenced from a static context" Here is a function I have public void addSong() { Scanner scan = new Scanner(System.in); Song temp = new Song(); int index ...

non-static variable cannot be referenced from a static context (java)

I ask that you ignore all logic.. i was taught poorly at first and so i still dont understand everything about static crap and its killing me. My error is with every single variable that i declare then try to use later inside my methods... i get the non-static variable cannot~~ error I can simply put all the rough coding of my methods ...

Java: static-non-static-this problem

$ javac TestFilter.java TestFilter.java:19: non-static variable this cannot be referenced from a static context for(File f : file.listFiles(this.filterFiles)){ ^ 1 error $ sed -i 's@this@TestFilter@g' TestFilter.java $ javac TestFilter.java $ java TestFilter file1 file2 file3 TestFilter.ja...

trouble accessing non-static functions from static functions in AS3

I have a class containing, among other things, a drop down menu. With the aim of saving space, and since the contents of the menu will never change, I've made a static DataProvider for the whole class that populates each instances menu. I was hoping to populate the list with actual functions like so: tmpArr.push({label:"Details...", fu...

Java Beginner Question : What is wrong with the code below ?

public class Function { public static void main(String args[]) { System.out.println(power(3,2)); System.out.println(power(3,2)); System.out.println(power(2)); } public long power(int m) { return m*m; } public long power(int m,int n) { long product=1; for(int i=1;i<=n;i++) ...

how to update a textbox from a static class?

This is driving me nuts. I have a working text based application. It has many many variables which now need a GUI. I'm starting with the basics. Whenever some data is sent to my log, I want it to display in my textbox. Here is a unified entry point for data to pass where it can be manipulated. public class Log { private static...