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 am currently working on a dice game. I have a private method called rollDice and it performs the action of rolling two dice. For my project, I need to create another method called playerRolls and I am supposed to invoke the rollDice method in the playerRolls method and perform actions based off of that. My question right now is how do I invoke a method into another method of the same class?
Java-code, When i compile the java doc. I get output;
Perceptron.java:12: learn(Instance[],int,int) in Perceptron cannot be applied to (Instance[],int) PerceptronModel model = learn(train_data,5); ^ 1 error
And here is the code
import java.io.*; public class Perceptron { public static void main(String[] args) throws IOException { DataReader reader = new DataReader(); reader.init(args);
I am trying to put a reference to a given subclass object into a linked list, and then come back later, and invoke a method of the subclass object that is in a given spot in the linked list. This produces an error because Object does not have that method. Is it necessary to cast the object to the correct subclass every time I want to use one of its methods, or is there a way to convince the JVM to treat it as always of type MySubclass?
Why is the equals-method in the super-class invoked? Shouldn't the equals-method in the sub-class be invoked(at least in the first if-statement since b2 is a B(i know B is also an A))?Is the equals-method overridden? Or does B have its own equals-method?
class SomeClass{ public static void main(String[] args) {
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 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();
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'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 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?
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
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();
class test { static int i=j; static int j=10; .....
this will give illegal forward reference ....
but this will compile successfully ..
class test { static int i=test1(); static test1() { return 20; } } .....
plz assume we have main method in both cases ..
java would be loading all static members first and would be assigning default values .. and then will be running all the initializers from to bottom ..Why second case is a compile success and not first .. as in second also test1 method is declared after its usage ..
I'm writing a program that calculates phone charges. I have my class is set up, but when I try to retrieve data from it in my main, eclipse says that I need to set my method to static, which messes up the rest of the program.
Class:
public class MobileCharges { private double charges; private int minutes; private String plan;
class One { public static void doStuff() { System.out.println("One"); } }
class Two extends One
[code]....
My understanding of static says that static methods cannot be overrriden but the compilation of the above code results in Overriding rule violation error.
