I have an arraylist, list, that I need to take the size to declare an array, arr3, in another class. Problem 1: the size is giving me an error of "can not make static reference to non-static method getListSize() from the type FindItemInfo". I tried to change getListSize() to static and it gives me and error another place. I try to then fix that, and I get a new error... and so on.
I am using arr3 to store items the user can not afford. I have this next problem even when I input an integer for the arr3 size. I am getting a NullPointerException, and I can't figure out why the arr3[] is not loading. I tried debugging but can not figure out where I went wrong, especially since this code was working in the last assignment before I changed list[] to an arrayList. It always breaks at line 64, but I believe it has to be somewhere in the cashOut() method.
Relevant code is:
public class FindItemInfo implements InterfacePrint{
ArrayList <ItemAttribute> list = new ArrayList<ItemAttribute>();
//does stuff
public void printPriority(){
TransactionCalc finish = new TransactionCalc();
I am getting a NullPointerException Error and I cannot seem to figure out what is causing it. I am reading in a grades1.dat text file and putting the values into a 2D array. The error is occuring in my addGrade method, but I am not sure what the error is. Here are the values for my grades1.dat that I am running in through Run Arguments in JGRASP.
Student1 5 a Activities 0.05 q Quizzes 0.10 p Projects 0.25 e Exams 0.30 f Final 0.30 a100 a95 a100 a100 a100 q90 q80 q100 q80 q80 r90 p100 p95 p100 p85 p100 e77.5 e88 f92
Here are the errors that I am getting.
Exception in thread "main" java.lang.NullPointerException at GradeBook.addGrade(GradeBook.java:114) at GradeBookApp.main(GradeBookApp.java:55) import java.util.Arrays; /** * Stores students name, a char array of category codes, a String array of categories, a double array of category weights, and a two dimensional double array of grades where each row contains all the grades in a particular category.
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 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());
I've got a problem in Eclipse. The below code is a part of my program, used for (re)starting a new game. The 'public static int' statement gives the error 'This method must return a result of type int'..
public static int playAgain(){ boolean validInput = false; do { System.out.println("Would you like to play a game? Please answer 'yes' or 'no'."); String playAgain = input.next();
I am using a static method to convert a string to an Integer object. Next using a instance method to convert Integer object to an int.
Compiler is giving me two "cannot find symbol" errors:
One pointing to the dot operator between "Integer.valueOf(s)"
The other pointing to the dot operator between "obj.intValue()"
I have latest JDK installed: jdk-7u51-windows-x64.exe
Looks like JCL installed correctly with rt.jar file located in "lib" directory under "Program Files"
Following is source code:
Java Code:
public class StringToInt { public static void main (String args []) { String s = "125"; Integer obj = Integer.valueOf(s); int i = obj.intValue(); i += 10; System.out.println(i); } } mh_sh_highlight_all('java');
I'm writing a code with a cellphone class to set price, brand and serial number. I'm also, in the main method, initializing 100 different cellphone in a matrix style ( up to here I'm fine). I have to use a copy constructor to define some cellphones ( fine too). Another thing I had to do was to generate random numbers and swap the price of the cellphones ( which I'm fine with too). My problem lies after using my static method. I have to display a new matrix with the changed price and return the counter that I used in my method to see how many times it was changed.
My two problems are that if I display my array again after I ran the method, it stays the same ( I didn't "catch" the change so I'm guessing the compiler just didn't keep them in the array). Secondly, I don't know how to return the counter. I don't have any ".getCounter" or something ( what I'm used to). Any input?
My formatting is terrible, I'm trying to improve it no need to point it out
Here's my code:
import java.util.Random; //Cellphone Class ( apart from main method) class Cellphone { private String brand; private long serialNumber; private double Price; //declaration of variables in cellphone class
I'm writing a code with a cellphone class to set price, brand and serial number. I'm also, in the main method, initializing 100 different cellphone in a matrix style ( up to here I'm fine). I have to use a copy constructor to define some cellphones ( fine too). Another thing I had to do was to generate random numbers and swap the price of the cellphones ( which I'm fine with too). My problem lies in my static method. I coded it all, but I can't seem to invoke it on the cellphone.
Basically, the method has to search for cellphones in the array with the same price, swap the price, print it out, and keep a counter of the price swap it has made. But I can't seem to invoke it on eclipse. It keeps telling me it is undefined for the class cellphone ( the method modifyCellPhone)
Here's the code:
import java.util.Random; class Cellphone { private String brand; private long serialNumber; private double Price; public Cellphone (String br, long sN, double Pr) {
I believe I am on the right track but when I run the program I get an error that the class that I can't call on the method. I need to have what is selected in the JCheckBoxes added to the toppings array and I can't get that done what so ever.
Java Code:
import java.awt.event.*; import javax.swing.*; import java.awt.*; public class PizzaOrderListener { public static void main(String[] args) { JFrame frame = new JFrame(); JPanel panel = new JPanel();
If the user enters the command line shown above, how many elements are contained in the array which is passed to "public static void main(String args[])" in TestCommandLine?
Choice 1 Four Choice 2 Five Choice 3 Six Choice 4 Seven Choice 5 Nine
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) ?
I 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
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)
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
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<>(""); } }
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.
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();
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?
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.
One class having two method one as static n another as non-static, 2 threads are there t1 is accessing the static method and t2 the non-static method is it possible n both are sharing the same object.
I now we have two kinds of lock one is object level lock and another is class level lock
