I am doing a multi threading program . I am unable to get the output i want. I have no compilation error . But I cant get the result I , Null exception. This is my Test program
import java.util.*;
public class Test
{
public static void main (String[]args){
int totalShares = 0 ;
double totalCost = 0.0;
String name = "FCS";
double profit = 0.0;
I'm trying to make a stock program that stops the user from entering in textfield and displays a message when stock is low. There's just 2 problem the entered value by the user is only decremented twice then the total stock resets for example with SofaTotal and the if statement doesn't work:
I'm making a stock system for the heck of it,so everything was going great until I hit the loop I am trying to use a for loop to add stock to the stock system,any way the question is maily about loops.How come I cannot declare a variable outside a loop and assign a value to it,for example I can declare as follows and I will not get an error,
but in my code(and yes its the only error I get I tested it) I get an error and can only declare and assign a value inside the loop,the reason for this is because I wanted to get the value from another class and use it in the loop ok so heres the code from both classes.
public class mainn{
public static void main(String [] args){ stock first = new stock(); int internal; internal = first.wanted;
This is my own coding for understanding deadlock in multithreading . But my doubt is whether this program mirrors the concept of deadlock perfectly or not. If not what should i do to make this code a perfect deadlock.
import java.io.*;
class A { B bc; synchronized void funcA(B b) { bc=b; System.out.println("INSIDE FIRST OBJECTS MONITOR");
I have a Stock Database query class, it compiles and runs well. Thing is when i enter a user, it shows a user stock information but it repeats showing the same user in the command prompt. the repetition is so fast, you can't see the information. All i wanted was the application to show a user's info, then asks you to enter another user again and so forth. Here is the code
import java.io.*; import java.sql.*; import java.util.*; public class StockDatabaseQuery { public static void main(String[] args)throws Exception { String userID; String firstName;
I am writing a simple program to simulate a traffic light. What I want is to make them glow after each 1 second, one by one. For example: Firstly Red, then after 10 seconds, red will be put to off and yellow will start glowing and then accordingly green. This process shall continue incessantly (Just for experimental purpose). I have some arrangement done but could not figure out how to put them together in run() method of Runnable interface. I know how interthread communication works. But could not find any logic in this case when three threads will run together.
import java.awt.*; import java.awt.event.*; import javax.swing.*; public class TrafficLight extends JFrame implements Runnable { JButton red, green, yellow ; TrafficLight()
I need to work with multiple threads in background in a JavaFX application. I have a screen with ten buttons and I need to 'bind' each thread with the button that started the thread. If the user pressed a button that had started a thread (in the main screen, MainController.java), I need to recover it to display the information that contains to display it on the controls of Details Screen ( a second screen, DetailController.java).
What Class do you recommend for this? Service?
[URL] ....
It is possible to name the threads with any of these classes?
I got a question in my last interview, its all about multithreading, interviewer asked me to write a program, to write the contents of three files(F1,F2,F3) in to a new File F4, using multithreading , first thread should read the first file and second thread should read second file, so the File F4 should contain F1's contents in first then F2's contents after that etc. I tried to give my best shot, but i couldn't get a way to ensure that the first thread is reading the first file and write to F4 then second thread reading the second file and writing once first file is written completely into F4 and so on ..how to do this?
[URL] I made a program that takes 2 stock values by URL tickers, and now I need it to draw a graph with the values for the 2 stocks, so they can be compared visually. So far my idea was to create 2 arraylists that consist of the values for each stock, so that I can draw the graph so that x always move with 1 step, and y0 is the first coordinate, and y1 is the second, and after that y1 is the first, y2 second etc.
I have Stock Tracker application running, everything works just fine, but when i hit the List Users button, i get an SQL Exception which says "Column bot found". I tried searching for the exception from the internet, but the answers didn't suit my needs. below is the Stock Tracker DB i think the exception might be coming from.
public class StockTrackerDB { private Connection con = null;
// Constructor: makes database connection public StockTrackerDB() throws ClassNotFoundException,SQLException
I am trying to write a small program that will calculate the gain and/or loss of the sale of stock. The program will ask the user for the number of shares, the purchase price and the selling price. I am pretty sure that the errors is coming from my calculations in the program.
import java.util.Scanner; public class investmentCalculator { public static void main (String[] args) { Scanner input = new Scanner(System.in); //User input for number of shares System.out.print("Enter the number of shares: "); double shares = input.nextDouble();
I have tried running the java application without adding the site to site list in java security tab. But I get a sand box message as APPLICATION BLOCKED BY SECURITY SETTINGS. How to run the java application without adding the site to site list in java security tab.
I want to develop a Java program that uses OpenScript APIs to test my applications. The OpenScript framework automatically creates the Java Code so I was thinking of either using this code or create my own using the APIs.
I tried both options using NetBeans but I'm getting errors everywhere starting with the library import. I'm pretty new to Java so I'm sure I'm missing a lot of things here. I pasted the code below from the OpenScript framework that want to use in a stand-alone file for your reference.,
I've written a java application with several classes all in the same .java file. It works just fine. Now, I've broken it up so that each class has its own .java file. Still works fine. My next step is to put those classes into a package, but I'm not about to get the program to run.The .java source files are all in /home/user/src
I've set the CLASSPATH to /home/user/src..All of the source files have "package com.myfirm.program" on the first line.I compiled the application with:
the compiler created the directory: /home/user/src/com/myfirm/program and put all of the .class files in there.So how do I get the program to run? if I run from /home/usr/src
java File1
I get: Exception in thread "main" java.lang.NoClassDefFoundError: File1 (wrong name: com/myfirm/program/Program)
In Main.java, How can i call method in CircleCalculationMethod.java ?
Should I put everything in same folder ??Should i do something like "import CircleCalculationMethod.java"Should i do something like create a package ...
The title of Question might seem old and previously asked.But I have a Question that what is difference between javaSE and Java EE.Although I knew what comes under JavaSE and What is under JavaEE.But My question is that.
What happens when we add PATH in our Environment Variable How does Eclipse or Other IDE use it?
Second Question is.
For Java SE we declare a Path Variable but for Java EE we do not add any library?(I know we add some jar file like for Servlet(Servlet-api.jar) and for EJB(Ejb.jar),But What is actaul difference?
I know about coding in general, Java, C, Python, SQL etc. but I barely know anything about making code come together on the web. I have a vague idea about what things like libraries and frameworks are,I'm interested in making a web application with which relies on Java do to the data processing. The idea is that the user inputs some messages, clicks submit, the text is taken away and processed, and the results are displayed on the screen. I would like the UI to be smooth with a modern look and feel.
Also, I usually do programming on Windows but I could also use Linux, so if I'll come across any specific drawbacks using Windows.
When I try to convert this value, "Testingu2120" (along with UTF coed u2120)comes as a string as part of SOAP response. I need to convert this UTF-8 characters in to a symbol, in this case it is SM (Service Mark) symbol and show it on the UI.
How can we achieve this in JAVA?
I have four different UTF-8 character set to convert.