public static void main(String... args) {
String i;
// String i = null; that would compile
if (i == null) {// this line does not compile as i was not initialized
System.out.print("A");
} else {
System.out.print("B");
i = "A";
main("A", "B");
}
}
Why does the above code not compile although the statement String i should lead to an initialisation of i to the value of null which is the default value for Strings.
I am facing difficulties in identifying the proper way to add the selected colors of cards into an arraylist. I am having an arraylist which is:
Java Code: private List<String> selectedCars = new ArrayList<String>(); mh_sh_highlight_all('java'); And one more for the carColors:
Java Code: private List<String> carColors = new ArrayList<String>(); mh_sh_highlight_all('java');
The selectedCards array will store the selected cars ['TOYOTA','MAZDA','NISSAN'] as per the selection from the user.For certain types, there is one default color which is 'Black', however for some of them, the user can select different colors.(ex. if selection is 'Toyota') Java Code:
String carColor=""; String toyotaColor=""; // The value will be retrieved from the form once the user selected the color if (selectedCars.contains("MAZDA")) { carColor="Black"; } else if (selectedCars.contains("TOYOTA")) { carColor=toyotaColor;
I am writing a program that accepts input from the user, I want default values displayed before the input values.
Java Code:
public surfboards() { surfboardType = "Type not assigned"; shaperName = "Shaper not assigned"; constructionType = "Construction Type not assigned"; surboardSize = 0D; } mh_sh_highlight_all('java');
I can get the output to display as shown below
(THIS IS WHERE I WANT DEFAULT CONSTRUCTOR DISPLAYED. Currently not displayed)
Type not assigned Shaper not assigned Construction Type not assigned 0 Feet
(THIS IS WHERE I WANT DEFAULT CONSTRUCTOR DISPLAYED. Currently not displayed)
input:
Java Code: Enter Surboard Type: test Enter Shaper Name: test Enter Surfboard Construction Medium: test Enter Surfboard Size: 6.5 mh_sh_highlight_all('java');
I am trying to make a game, for some reason i have begun to get a java.lang.StackOverflowError.
I am not exactly sure how i can fix it. only removing line 14 from infopannel1 (and everything that used that class.) seems to work. im not sure what else i can do to fix it. or why its resulting in stack overflow for that matter.
I am putting in a link for the files i wrote this using bluej (several classes have no relevance, errorv2, demonstration, folderreadertest, ReadWithScanner, saveloadtest, menutest,rannum, and menutestTester. are all irrelivent to my problem.)
I came across this code which proves that variable initialisation occurs before even constructors are called.However, I am confused over some things.
Firstly, from my understanding, when a new House object is created in this line House h = new House(); , the no-arg constructor of the House class is called.
Since the no-arg constructor House() is called, why are all the creation of Window objects being run first ? Shouldn't Java jump straight into the no-arg constructor House() ?
class Window { Window(int marker) { System.out.println("Window(" + marker + ")"); } } class House { Window w1 = new Window(1); // Before constructor House() { // Show that we’re in the constructor: System.out.println("House()"); w3 = new Window(33); // Reinitialize w3
I am using netbeans 7.2, glassfish 3.1.2, JSF 2.1 and Primefaces 3.2. When I add more than three menu tabs, I get this error ui layout initialization error the center-pane element does not exist the center-pane is a required element. This is my template.xhtml code:
<?xml version='1.0' encoding='UTF-8' ?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" xmlns:ui="http://java.sun.com/jsf/facelets" xmlns:h="http://java.sun.com/jsf/html" xmlns:p="http://primefaces.org/ui">
public class SavingsAccount extends Account { private static final double MIN_BALANCE = 100.00; private static final double RATE = 0.035; public SavingsAccount(Customer customer, double bal, String accountNum, Transaction[] trans) { super(customer, bal, accountNum, trans);
[code]....
When I execute this code there is an error in Transaction array initialization. Change the Saving account constructor from (String customer,double balance, String accountnumber,Transaction[] tr) to (String customer,double balance, String accountnumber,Transaction tr)
Now If I hit /Allen it sets init parameter for both servlet MyServlet and jsp JjspInit. I don`t have any servlet all I have is a web.xml and a jsp page. But accessing JjspInit.jsp directly gives null.
How hiting the url /Allen prints valu. This code is on JjspInit.jsp .
So does that mean that in web.xml I have registered this jsp as the target for /Allen. And one more question directly accessing the jsp page shows null it means init parameter haven`t been set.
if, instead of an ArrayList, can I do the following to initialize a Dyanmic array ? :
First, in my class, I have :
class Example{ private int rows; private int columns; private AnotherClass[][] 2DArray; public Example(int rows, int columns){ this.rows = rows; this.columns = columns;
Now if I am in the admin 1 environment, I would initialize my servlet with request parameter admin=1 and the servlet should load email address of admin 1 and similarly when in the environment 2, should load the servlet with admin 2.
I could do the same by putting the email address of the respective admin as request param value, but i don't want to the email address to appear in the url.
class A { final Object b; public A(C c) { try { b = c.someMethodThatMayThrowSomeException(); } catch (SomeException e) { b = null; // This line results in compiler error: "variable b might already have been assigned" } } // take away b=null line and you get "variable b might not have been initialized" on this line }
Why? How could 'b' be assigned if the exception was thrown?
/* * To change this license header, choose License Headers in Project Properties. * To change this template file, choose Tools | Templates * and open the template in the editor. */ package vecchiogiovane; import java.io.*; public class Vecchiogiovane { /** * @param args the command line arguments */ public static void main(String[] args) throws Exception{
[Code] .....
run:
run:
ins first name: aldo ins first age: 35 ins second name:
/* * To change this license header, choose License Headers in Project Properties. * To change this template file, choose Tools | Templates * and open the template in the editor. */
I've been trying to finish this blackjack program I have been making for my programming class, however, there are a few bugs I can't seem to iron out. It's a pretty short program, it's just that I'm an idiot and can't figure basic stuff like this out. Specifically, when I try and run it, I get this error:
Error occurred during initialization of VM java.lang.OutOfMemoryError: unable to create new native thread
The LocalStudent class inherits the Student class. The IDE states an error of "no default constructor in Student class".I understand that if a LocalStudent object is created, the default constructor of its superclass (aka Student class) will be called implicitly.there is no LocalStudent object being created, so why is the default constructor of Student being called ?
The default constructor of LocalStudent is also overloaded by the created no-arg constructor containining subjects = null; . So there is no call to the superclass default constructor from the default constructor of LocalStudent.
public class Student { private char year1; public Student(String name, char year){ year1 = year; } public char getYear(){ return year1;
Will I'm tying in my code to set a default number for the JTextField that when the user decide not to put any numbers. Like let say that I want the textfield set to 0 , so then the user do not file it it won't make any problem to the program because its already has a default number.
Note: This is a small part of my code. when I leave it empty it take the 0 as a value, However, when I write in text field it also take the value of a 0 and the finalTotal is also = to 0.what I'm doing wrong.
