I am getting a syntax error saying I cannot reference a non static variable from a static perspective.
How this is happening is with my variables declared in the beggining. When outputting those variables in my last statement, I am not allowed to.
The source is below.
I am trying to call an actionListener which is shown below in my PSVM :
class testMenuItemListener implements ActionListener {
public void actionPerformed(ActionEvent arg0) {
getContentPane().removeAll();
createPanel();
getContentPane().add(panel1); //Adding to content pane, not to Frame
repaint();
printAll(getGraphics()); //Extort print all content
[Code] .....
I get the following error :
Frame.java:409: error: non-static variable this cannot be referenced from a static context
menuItem1.addActionListener(new testMenuItemListener());
I am trying to add a field (called special) to a hibernate table. I am copying existing code (related to the NAME field) so I don't have to figure this out from scratch. I am getting the error
"[ERROR] C:VOXvoxware-1.1.13voxwarevoxware-implsrcmainjavacomvoxwareimplflowVoxFlowConfiguration.java:[213,38] error: non-static variable special cannot be referenced from a static context".
Line 213 is in public void mergeFrom, the actual line is "special = VoxFlowConfiguration.special;" I don't understand why Java thinks special is a "non-static" variable but it doesn't have a problem with the other variables (such as name, orderShow)
package com.voxware.impl.flow;
import com.voxware.asset.LiabilityType;
import com.voxware.flow.FlowConfiguration;
import com.voxware.flow.OrderFlow;
import com.voxware.flow.Step;
import com.voxware.i18n.LanguageCodes;
import com.voxware.impl.i18n.UTF8Control;
import com.voxware.impl.persistence.BaseEntity;
import com.voxware.impl.portal.VoxPortal;
[code]....
I am trying to call an actionListener which is shown below in my PSVM :
class testMenuItemListener implements ActionListener
{
public void actionPerformed(ActionEvent arg0) {
getContentPane().removeAll();
createPanel();
getContentPane().add(panel1); //Adding to content pane, not to Frame
repaint();
[Code] .....
I get the following error :
Frame.java:409: error: non-static variable this cannot be referenced from a static context
menuItem1.addActionListener(new testMenuItemListener());
The error said : Non Static Variable TAShaReport Cannot referenced from a static context
I just want to put the output in the TextArea
Here is the code :
public static String DeduplicateFiles(String myFolderLocation) {
try {
HashSet<String> newset = new HashSet<>();
File folder = new File(myFolderLocation); //Directory where the files are located
File[] listOfFiles = folder.listFiles();
[Code] .....
I am trying to compile the following code where the entry point is Main.java but i am getting the following error "Error non-static method add(int[]) cannot be referenced from a static context in Java " ....
If i add the keyword static in add method of A.java it works properly......
Class Main.java code
package com.company;
public class Main {
public int [] a= new int[]{1,2,3};
public static void main(String[] args) {
Main n= new Main();
[Code]...
Both the classes are in same package
This is a someway special question, because I am using jmonkeyEngine.
But the topic is simple:
I have 2 classes:
public class Spielbrett extends SimpleApplication {
public static void main(String[] args) {
Spielbrett app = new Spielbrett();
app.start();
}
@Override
public void simpleInitApp() {
[Code]...
as the main class and a second class for the chips:
public class Spielstein {
public Spatial stone;
public int player;
public int team;
private AssetManager assetManager = Spielstein.getAM(); //THIS IS THE PROBLEM
public Spielstein(int t_player, int t_team){
[Code]...
My problem is: I can't access getAM() from the first in the second class. If you know why I would be glad for an answer.
One of my friend asked me that which will load first static variable or static block ? My answer was to static variable.. So he gave me two program and said to differentiate between them
1st program
public class Test {
public static void main(String args[])
{
System.out.println(Test.x);
}
static {
System.out.println(Test.x);
[Code] ....
Output of this :
90
90
I tried to decompile the byte code and found it's same for both the above equation. How to differentiate between them. I am confused when the static variable will initialised.
I wrote a code to use static class. But, when I call the class in a outer class but, it gives an error. Is it mandatory to have a static class should have static variables when we declaring them??
public class StaticClassMain {
static class Sub{
String str="Example 1";
}
public static void main(String[] args) {
System.out.println(Sub.str);
}
}
I have a class Tree in which all the methods to build a tree are in place. But however I would want variable of by Tree which is pointing to the last node being added to the tree.
So basically every time you keep adding a node to the tree you tail pointer gets updated to point to the last node. I have this so far.
public class NonEmptyTree implements Tree {
private Tree left;
private int data;
private int leftleafCount;
private int rightleafCount;
private Tree right;
private Tree tail; // This variable must be shared by all the object. There needs to just one tail pointer to the tree.
public Tree insert( data ) {
tail = // gets updated every time when new node gets added.
Sandwich class. I have thus far completed creating a sandwich class with a seperate sandwich Tester class to run with it. (this is according to the assignment). Now I must create Static variables for the sandwich class:
Add two static variables to the Sandwich class to count how many sandwiches are sold and how many slices of tomato are used. Initialize each to 0.Where do you add code to increment the sandwich counter? Determine this and then add code.
public class Sandwich
{
static int numOfSold = 0;
static int slicesUsed = 0;
private String meat;
private int numOfSlicesOfTomato;
private boolean lettuce;
[code]....
How can i take run time value for static final variable...my lecturer said first time assignment is possible for declared final variable but in my case it shows compile time error..I'm placing my program below with error message
class Sample
{
static final String cname;
void print() {
System.out.println(cname);
}
public static void main(String args[])
{
cname=args[0];
Sample s=new Sample();
s.print();
}
}
Sample.java:11: cannot assign a value to final variable cname.
cname=args[0];
Suppose I have a class child
public class child{
public static int age = 1;
}
And I am using class child static variable age in class school
public class school{
int var_age;
public school(){ //school constructor
var_age = child.age;
}
}
Value in age of child class could be any of these below depending on some logic:
public static int age = 1;
public static int age = 2;
How could i achieve this where should i apply that logic? Also it is mandatory for class school code to remain same.
What happens to a static variable that is defined within a method of a class ?
View Replies View RelatedI'm not really sure I understand the functional difference between a static and final variable/field. Oracle defines Class Variable as:
Class Variables (Static Fields) A class variable is any field declared with the static modifier; this tells the compiler that there is exactly one copy of this variable in existence, regardless of how many times the class has been instantiated. A field defining the number of gears for a particular kind of bicycle could be marked as static since conceptually the same number of gears will apply to all instances. The code static int numGears = 6; would create such a static field. Additionally, the keyword final could be added to indicate that the number of gears will never change.
If static will have the same value regardless of how many times it's used, then why use final (or vice versa)?
Here is my code. Obviously this doesn't do a lot but that's only because I abstracted out the problem so there are not many lines to decipher.
Java Code:
import java.util.Scanner;
class threadOne extends threadTwo {
public static void main(String[] args) {
threadTwo threadTwoObj = new threadTwo();
threadTwoObj.start();
while (!userInput.equals("exit")) {
[Code] ....
What its supposed to do: When the user returns "exit" in the console it is supposed to break out of both while loops in both threads.
What it actually does: breaks out of the while loop in threadOne and not in threadTwo.
Basically the idea is to have a thread running doing computation and another thread able to query it for updates or interact to make changes to the flow. This will be useful, among other ways, for the sorts of problems where finding a solution is easy but where a better solution can always be found with more time. So for example finding directions on a map. Its easy to find a solution, but if you search longer you can find a faster route, if you search longer still than faster still.
What I'm trying to do is display an entire deck of cards in 4 hands, randomly shuffled. These will be displayed as images in a pane. The images are numbered 1-52(not using Jokers) so what I have done is created an array that contains those numbers. Then I am randomly shuffling that array. What I can't figure out how to do is display the images using the randomly shuffled numbers in the array to do it? Is this even possible or am I totally on the wrong track on how to do this? This seemed like the obvious way to go when I started. Showing images isn't a problem, it's showing them using the array's element to get the image name that I'm having trouble figuring out.
View Replies View RelatedThis is my code inside the method:
@Post
public static String getDetails(Representation entity) throws Exception {
String customerId = getQuery().getValues("cus_id");
}
I use this code in Restlet Representation. I try to get the value from the Request API. But I am facing the problem as "Cannot make a static reference to the non-static method getQuery() from the type Resource".
From what i understand static methods should be called without creating an instance of the same class . If so why would they return an instance of the same class like in the following : public static Location locateLargest(double[][] a) , the Location class being the same class where the method is defined . I don't understand this , does it mean that every field and every method in the class must be static ? Meaning that you cannot have instances of the class because everything is static . Or it's just a mistake and the class Location cannot have a static method: public static Location locateLargest(double[][] a) ?
View Replies View RelatedI can't figure out what this error message "Cannot make a static reference to the non-static method getEndUserCharge(long, long, long, long) from the type UpdateUserWS" actually means.
The error is coming from:
public void updateDetailsPackage() {
some unrelated code
long zero=0;
double endUserCharge=0;
endUserCharge = UpdateUserWS.getEndUserCharge(long zero, long zero, long zero, long zero); <-------- error is here
[Code] ....
Alright, I have two classes, this one
public class Player {
private String player;
public String getPlayer() {
return player;
}
private int strength;
private int defense;
[Code] .....
However, it says that under Player.getPlayer() that it 'Cannot make a static reference to the non-static method'.
Why I can create an Instance of a class that contains non static variables within the static main method ?
This program runs fine
import java.util.*;
public class Test{
public int j;
public static void main(String[] args) {
Test test1=new Test();
System.out.println(test1.j);
[Code] .....
I'm working on a banking program that is supposed to use 3 classes (Account-base class, CheckingAccount, and SavingsAccount) and several methods to display the banking information (ID, balance after a withdrawal and deposit, and the annual interest rate). This should be a pretty simple program, but I'm getting hung up on one portion of it. I'm getting some compiler errors, all of which deal with non-static variables being called from a static context (I'll also post these errors following the code). Up until the middle of last week, we just declared everything as static, but that's changed and I'm having trouble figuring out when to and when not to use static when declaring my methods, hence the compiler errors.
import java.util.Date;
public class Account {
private int id = 0;
private double balance = 0;
private double annualInterestRate = 0;
private Date dateCreated = new Date();
[Code] ....
Here are the compiler errors I am receiving:
Compilation completed. The following files were not compiled:
6 errors found:
File: C:UsersHiTechRedneckDesktopSummer II 2014Computer Programming PrincipleProgram 5CheckingAccount.java [line: 7]
Error: non-static method getId() cannot be referenced from a static context
[Code] .....
I am writing the following program in Java SE 7. It throwing "Cannot make a static reference to the non-static type String" . However if I write parameterised String inside main method as java.lang.String[] args, it compiles fine.
class MainClass<String> {
<T> MainClass(T t) {
System.out.println(t.getClass().getName());
}
public static void main(String[] args) {
System.out.println("asdasd");
new MainClass<>("");
}
}
I mean following programs compile fine in Java SE 7 :
class MainClass<String> {
<T> MainClass(T t) {
System.out.println(t.getClass().getName());
}
public static void main(java.lang.String[] args) {
System.out.println("asdasd");
new MainClass<>("");
}
}
i am trying to make something, and i want to request input from user and it shoud look like this
1. xxx -> press 1 to choose this
2. xxx -> press 2 to choose this
So if they enter 3 or string or whatever i want to restart method and show again
1. xxx -> press 1 to choose this
2. xxx -> press 2 to choose this
So here is method that i am trying to restart
public static void askUser(){
System.out.println("xxx");
System.out.println("1. xxx");
System.out.println("2. xxx");
System.out.println("3. xxx");
[code]....
If i try to make it public void than it say can't call non-static methods inside static(main).if i try to put it into new class and then call it after i fail input it goes into infinite loop.
I had a TestColor class which contained methods to change hue, saturation, brightness, red, green, blue of TestColor's instances but also had static methods which take in an additional parameter for an instance of TestColor and returns the affected instance of TestColor. Now instead of having one method for every possible color effect to be applied to an image, how can I have one method that takes in an Image parameter, a static or non-static method reference from TestColor parameter and lastly an intensnity value parameter. This is so that I can make an affectedImage object instance inside the method and a Graphics2D object for drawing to each pixel of the new image, now I have one for loop and one nested for loop for the x and y pixels of width and height of the old image and inside the nested for loop I'd create a TestColor by calling getRGB on the image's pixel. Then I would apply the static or non-static method reference somehow to change the color with the intensnity value and after applying it draw to the new Image with Graphics2D. How to would I parametize a method reference and be able to use it in such way?
View Replies View Related