Am facing a very strange issue. While trying to compile a very simple Hello World java program, the compilation completes successfully without any error or warning, but it does not generate the class file.
It happens when I compile with a particular jar file, otherwise compiling only the program (or with any other jar) does generate the class file. I am using java 1.7.0_45.
I've a .java file that won't compile, but produces no errors (in cmd prompt).
I think its the import of java.util.ArrayList thats causing the problem (because it can compile a different file in the same source folder) - so i'm assuming its the classpath that is wrong. which is fine. i love fighting with classpaths.
But why isn't it providing me with an error. the compiler usually goes bat-sh.. crazy if the -cp is incorrect!
Its because I'm switching between command prompt and a text editor and it hadn't saved the file for some reason, and still won't am getting rid of this editor!!
I was doing coding exercise from a book ('OCP Java SE 6 - Practice Exams' by Kathy Sierra and Bert Bates). I came to a question that told to demonstrate the difference between 'default' and 'protected' access rules by creating/making a directory structure and putting a couple of classes in different packages.
For this, I made a total of four classes, out of which, three classes are-Car, TestingCars, CarDimensions. (The fourth is not yet used in testing code till now, so, I am giving only the other three classes.) Their coding is given below.
Out of these classes, the classes- TestingCars and Car - are in a directory (say, FolderName). And, the class- CarDimensions is in FolderName's sub-folder.
The class 'CarDimensions' is public (and its components too are public). And, I am testing all the classes from the class- 'TestingCars'. But, this class (TestingCars) is not able to find the public class- 'CarDimensions' which is in its sub-folder and gives two 'Cannot find symbol' errors citing the class-CarDimensions. Also, If all three classes are put in one single directory, the programs work, without any error.
Coding:
Class TestingCars:class TestingCars {
public static void main(String[] args) {
Car c = new Car();
c.setType("FourWheeler");
[Code]....
I could not find why the public class- CarDimensions- is not getting found by the TestingCars class.
when i try to compile following source file, there is a error which states "MovieTestDrive is public, so must be declared in a file MovieTestDrive.java" i didnot understand. i am beginner in java;
class Movie
{
String title;
String genre;
int rating;
void playit()
{
System.out.println("playing the movie");
}
}
public class MovieTestDrive
[code]....
I am designing simple app which would store data about users and generate standard letter and print sun ray card for this user. I know how to build UI, how to validate it etc. I know how to store data in database, but I don't know how to deal printing.
I have MS doc template documents they contain jpg pictures, and unusual formatting Is there a way of actually pulling those templates and do the merge and perform print operation? If it is not easily done, what else I could do? I would need to have option to easily edit those templates in case of any changes.
Well I want to generate a license key for my software product. I'm aware of Google's Guava Libraries for generating alpha numeric license keys. But I'm thinking it to do in a different way without using any such libraries or specifically guava libraries. Till now this is my plan that,
1. Get a MAC ID / IP Address of the system in which the application will be installed and ready for it's first use.
2. Store that MAC ID in a UNCOMMON File format in client's PC only.
3. And what should be the next step.?
I'm making a java program that can "convert" java to arduino by sending commands over a serial port. I'm using the JSSC library, and using methods to shorten things up a bit.
I've already made the code that starts up the serial port and it does connect. But I've made two different classes for the methods. One for the RXTX and one for the Arduino.
I'm making it so that I can just type:
Java Code:
public static void main(String[] args) {
RXTX.SerialSetup();
Arduino.pinMode(2, 0);
} mh_sh_highlight_all('java');
And it will start the serial port and set pinmode on pin 2 to output.
But when I try it I get this error:
Java Code:
Exception in thread "main" java.lang.Error: Unresolved compilation problems:
serialPort cannot be resolved mh_sh_highlight_all('java');
I don't know if its possible to 'send' a variable to a different method.
Each time i create a new project or try to compile my workflow (run as GenerateDemo.mwe2 file by write clicking on the file the run as --> WME2 Workflow) it prompts the error I've attached the picture of.
What is it for? How can i get rid of it?
I tried running this program but shows some compilation error of cannot find symbol . in following:
p1.num, p2.num and p3.num
cass Guessgames
{
void startgame()
{
Players P1=new Players();
Players P2=new Players();
Players P3=new Players();
boolean p1isright=false;
boolean p2isright=false;
boolean p3isright=false;
int guessp1=0;
[code].....
I want to know if there is any general rule/pattern about things which give compilation fails and things which go for Runtime error/exception. OR only way is to remember all of them and there is no actual pattern in it.
View Replies View RelatedI'm having some difficulty getting this GUI dice game to compile. I'm using javac and notepad++ for this and I'm getting the following errors:
DiceGame.java:34: error: cannot find symbol
die2label = new JLabel();
^
symbol: variable die2label
location: class DiceGame
[Code] ....
4 errors
My code is as follows:
import java.awt.*;
import java.awt.event.*;
import java.util.*;
import javax.swing.*;
import javax.swing.event.*;
public class DiceGame extends JFrame
[Code] ....
I'm sure the problem is something trivial, but I guess that's all part of the learning process that I have to go through.
We are getting "Code too large" compilation error for one of our class. This class contains public String fields for label ID and value. We use this class for localization, except for English all other language labels come from .properties files.
The reason we are getting this error is because we have a static block in which using reflection we are populating a HashMap with all public fields and their value. The number of fields have gone up to the extinct where we are crossing the 64K limit for a static method. One of the most feasible solution was to use .properties files for English labels as well.
I will be calling this class MyLabels. We defined a super class for MyLabels called MyLabelsExt. And now we are adding labels into the super class instead of the MyLabels. By running some tests we confirmed that the map that we initialize in MyLables class contains all the fields from both MyLabels and MyLabelsExt class.
How is the 64K limit error not coming if the labels are defined in a super class. Does that mean Java is able to identify that some of the fields are coming from parent class, and that is being treated as separate from the child class. And how is the map that we initialize having all the value.
I have a simple doubt
float k = 0;
k+=0.2;
k=k+0.2; // here compilation error
compliation error Type mismatch: cannot convert from double to float
My question is why not a complilation error at k+=0.2;
My random integer always seems to be zero.. I am at the ends of my wit.
package Exercises;
import java.util.Random;
import java.util.Scanner;
import javax.swing.JOptionPane;
/**
* Heads or tails?
* That is what this is.
*/
public class num14 {
[Code] ....
Attached File(s) : New Text Document.txt (2.59K)
try {
File configFile= new File("C: Documents and SettingsstudentMy DocumentsNetBeansProjectsCDASsrcconfig.xml ");
DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();
Document doc = dBuilder.parse(fXmlFile);
doc.getDocumentElement().normalize();
NodeList nList = doc.getElementsByTagName("config");
[Code] .....
This code is working properly but i have use path like this
File configFile= new File("srcconfig.xml");
Instead of system directory path i have to use path inside of project but i am getting an error-cannot find the specified file...
Is it a good idea to use the date and time with the first or last few values of the session ID. Or should I just use the complete session ID value for my "unique id"?
View Replies View RelatedI want to call getter method from method based on parameter send to this method e.g
Java Code:
void myCrazyMethod(MyDto dto, String prop){
System.out.println("Value of " + prop + ": " + dto.get{Prop}()");
} mh_sh_highlight_all('java');
My project is writing a program that generates a series of numbers to appear like a social security number (XXX-XX-XXXX). My code runs.. But any number below 10 it just shows one number (XXX-X-XXXX). What do I need to enter in to my code so that if the number is <10 it will show (00,01,02,03....)?
Java Code:
import java.util.Random;
public class IDnumber
{
public static void main (String[] args) {
Random generator = new Random()
int num1 = (generator.nextInt(7) + 1) * 100 + (generator.nextInt(8) * 10) + generator.nextInt(8);
int num2 = generator.nextInt(74);
int num3 = generator.nextInt(10000);
String IDnumber = num1 + "-" + num2 + "-" + num3;
System.out.println(IDnumber);
}
} mh_sh_highlight_all('java');
I have a problem in generating reports using java code. I created a report using iReport 5.5.0 with MySql Database connection. In iReports, it shows the correct output while previewing it. Then i copied my .jrxml file and pasted it into my netbeans project folder(..sample/web/WEB-INF/sample.jrxml) and then i added the required jar files in my project's library folder. i am generating the report in netbeans using jsp and servlet. THE REPORT IS GENERATING AND SAVED SUCCESSFULLY IN MY DESKTOP. BUT IT DOESN'T GENERATE THE REPORT FOR FIRST RESULT. For Example.., if i generating report based on a particular date. After executing the query, it returns 4 results. So it has to create the reports in 4 pages. But it generates the report for last 3 pages only. It doesn't generate the report for first page. I have attached my .jrxml file servlet file for your reference.
View Replies View RelatedI have been set this task, which is supposed to make me code using string arrays. The idea is to generate random sentences.This is what i have been able to do so far :
package usingarraysagain;
public class sentences {
public static void main (String[] args){
String[] NOUNS = { "lizards",
"Nikola Tesla",
[code]....
I am trying to change this code to use only integers to calculate the compound interest.
// Compound-interest calculations with for.
public class Interest {
public static void main( String args[] ) {
double amount; // amount on deposit at end of each year
double principal = 1000.0; // initial amount before interest
double rate = 0.05; // interest rate
[Code] .....
And here is the output I get :
Why do I get the output after year 2? I assume it has something to do with the remainder.
I also have to format this output with the decimal point, etc.. which I think I will be ok with after I get through this part.
I've been trying to find the easiest way to write to generate a number which is between intervals of a arbitrary min and a max value.I've been searching for this but I don't find this particular thing.I've found that this combination works:
Java Code: int guess = rand.nextInt(max - (min - 1)) + min; mh_sh_highlight_all('java');
But I wonder, is this really the easiest way of writing it?
I am very new to programming. This is for a college assignment. It says in the brief of the assignment that we will need to convert Math.random to output a random number between 1-1000. How can I do this?
View Replies View RelatedI am working on a bingo project and created random numbers between 1 and 75 to generate. I have it set up that it shows the number in a text box and changes the color on the board if the number is called. When I test the program, some numbers are highlighted in addition to the number called. I believe this is because extra numbers are being chosen, but not being noted in the text box. Below is my code for the unique random numbers.
int CallNo;
String CallerTxt = new String();
public void CallNum() {
Random RandCall = new Random();
//Generate Caller Random Number
CallNo = RandCall.nextInt(75)+1;
[Code] ....
The program I'm supposed to create generates a random number between one to ten. Then the program is to ask me if I wish to cross the road.
If you choose to cross, the outcomes for 0-2 are "You crossed safely."
For 3-5, 75% of the time it should say "RIP you got run over", and 35% of the time it should say "You crossed the street."
For 6-8, 60% of the time it should say you made it.", and 40% of the time it should say "You died". For 9-10, it should say "RIP".
So far I have gotten the random number generation part working,
import java.util.Random;
public class test4 {
public static void main(String[] args) {
Random random = new Random();
for(int i =0; i < 1; i++){
int num = random.nextInt(10) + 1;
System.out.println("The number of cars on the street are: " + num + "
Do you wish to cross the road?");
}
}
}
After generating a. JAR with Netbeans Java, when I play I see the colors of the components, the design and formatting is lost and the form gets a very basic formatting, for example, if I set a button with the color [0, 40.255] and build the. JAR after this, when I run the. JAR this button turns gray, and it happens with all the layout of the form.
settings:
Netbeans 8.0
Windows 7