Creating User Defined Packages And Importing
Aug 29, 2014My question is How to write a program to implement concept of creating user defined packages and importing the same? How to solve it.
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Importing And Creating Objects From The Text Files?
May 25, 2014I've been trying to write a program for some time now, but im encountering problems while trying to complete it. The program has a student class and a course class (set up with some info about the class, like #, professor name, course title, course time). Now, i have a text file in the workspace, and i have to import the data from the textfile, and thats just what i did, but then there is an option which allows the user to delete a course only by inputing the course number, and when he does that, the program outputs the course's name, and confirms the deletion of the course (From the student's record, i created a vector for that and imported all the courses from the text file). But how can i let the program know what's the name of the course when the user inputs the course number ???
When the data is read from the file, objects should be created and added to the student's course record. <- i think here's where i messed up ? i imported the data, but how can i actually make them objects before adding them into the vector ?
PHP Code:
public static void main(String[] args) throws IOException
{
Scanner scan = new Scanner(System.in);
Vector Record = new Vector();
try {FileReader filereader = new FileReader("CLASSES.txt");
BufferedReader bufferedreader = new BufferedReader(filereader);
String test = "";
while(test != null)
{
Record.addElement(test);
test = bufferedreader.readLine();
} mh_sh_highlight_all('php');
Calling A User Defined Exception?
Dec 3, 2014I know that I am not 100% comprehending try/catch blocks, but after scouring message boards, forums, and Oracle, I still can't pick out where I am going wrong.
I have a ValidateInput class where I am trying to check that a String only has letters. If not, then throw an exception message via JOptionPane. I created my own NonLetterException class. When I call the method containing the try/catch Eclipse gives me an Unhandled Exception Type error.
in main()
ValidateInput validate = new ValidateInput();
String name = "error";
for(int x = 0; x < 1;){
name = JOptionPane.showInputDialog("Welcome. What is your name?");
boolean isItName = validate.stringInput(name); //error appears at validate.stringInput
if(isItName)
[code]....
Aren't I handling it in the try/catch? What did I miss?
Also, I have have tried the NonLetterException class as nested in ValidatedInput, but also not nested. To me nested makes more sense. I have never nested classes before, but it makes sense to me because I am not using this exception in other parts of my program.
Differentiate System And User Defined Classes
Mar 16, 2014How Can I differentiate the System classes and user classes in my program written below by another program?
/**
* Employee Class containing all non-primitive data types.
*
*/
class Employee{
private String name;
private String phone;
private Integer age;
private Float salary;
[Code] ....
Any Technique that will decide which one of the fields (Integer, Address, DOB, String, Float) are user defined type. (An outsider class should used that will identify the Java classes and the user-defined classes.)
Adding User-defined Int To Existing Array?
Apr 7, 2015how to add an a user defined int into my existing array. Ive heard of using ArrayList but not sure how to implement it.
View Replies View RelatedDifficulties With User Defined Variable In Multiple Methods
Apr 9, 2015I'm trying to build a program that will output what will ultimately look like a simple mario level turned on its side. As part of my output I need the user to define what mario looks like. I do this using Scanner and save the input to String mario. When I try to use that variable in another method it gives me troubles.
import java.util.Scanner;
public class Mario2
{
public static void mario() {
//user defines mario
String mario = ">->O";
Scanner keys = new Scanner(System.in);
System.out.println("What does mario look like?");
mario = keys.next();
System.out.println("Mario now looks like: " + mario);
[code]....
ArrayList Contains Method Does Not Work On User-defined Data Types
Sep 1, 2014I am trying to remove the duplicate elements from ArrayList using .contains() if elements are primitive datatype it works but user-defined datatype does not work.
public class UserBean {
String name;
String address;
public String getName() {
return name;
[code]....
Write A Statement That Reads User Input Integer Into Defined Variable
Jan 20, 2015so i'm following a java tutorial from the book and it has a few challenge questions. and i'm stucked on one. i think i just don't understand what is it that its asking me. heres the question, Write a statement that reads a user's input integer into the defined variable, and a second statement that prints the integer. assuming scanner is given, and i checked my heading code is ok.
Scanner scnr = new Scanner(System.in);
int userNum = 0;
System.out.println("What is the product of 8 time 2");
userNum = scnr.nextInt();
[code]....
JSF :: How To Read CSV File From User Defined Directory Path For Loading To Managed Bean
Jan 10, 2015I'm using a PrimeFaces UploadedFile xhtml page to select a csv file to read and write using a managed bean (SuperCSVParser.java). The file is read and written to an entity class which then persists the data to a database. The application works fine if I specify a file path on the physical server and select a csv file on that file path. But for the production version I want the user to select ANY file name from ANY directory on their local system.
I know about the FacesContext methods and I've looked at some methods from the java.io File class. Most of these methods are about getting the path from the server, where I want to 'pass' the path String from the client machine to allow the uploaded file to go through. When I try with the below code I get:
java.io.FileNotFoundException: data.csv (The system cannot find the file specified)
I'd like to know what I'm doing as I prefer not to explicitly declare a path in the final app. I'm almost sure that's possible.
<h:form enctype="multipart/form-data">
<p:fileUpload value="#{SuperCsvParser.file}"
mode="simple"
auto="true"
[Code].....
Does Importing Whole Package Use More Memory Than Only Importing Specific Package Parts?
May 22, 2014Let's say hypothetically you're making a huge program and use a lot of imports (ex import java.util). If you only need a few specific things from java.util, will it use more memory importing java.util.* compared to only importing lets say java.util.Scanner, java.util.ArrayList, etc. Basically does importing a whole package use more (if any at all) memory than only importing specific package parts?
View Replies View RelatedAccessing Objects From Other Packages
Dec 7, 2014I have GameConsole class with gamePlay(). There are two objects in this class that I want to access from a class in another package.
package blackjackControls;
public class GameConsole {
Player dealer; //both of these objects I am trying to bring over into the blackjackGUI package
Deck playingDeck;
public void gamePlay(){
[code].....
The dealer and playingDeck objects are giving me an error of unresolved. the way it is written I also get a static error on line 37. I know that I have not yet written in the actionEvent statement in the button constructor.
Packages And Exception Handling?
Aug 17, 2014Is there any connection between packages and exception handling in java. Means is it necessary to create a package before trying exception handling examples?
View Replies View RelatedWhat Happens With Imported Packages From API At Compile Time
Aug 26, 2014I was wondering what happens to the API packages I've imported at compile time. Are they compiled to classes and placed In the same file as the class containing the Import command ?
The reason I'm asking Is because I've noticed the src.zip file Is not In the JRE and since the JRE Is all that's needed to run an app , I'd like to understand what the import command does.
Naming Conventions For Java Packages
Mar 14, 2014So I'm not entirely sure what to name my packages. Sometimes I have to many and it becomes overwhelming. Sometimes I don't have enough and I cannot keep my files organized. What is a good naming convention for Java packages?
View Replies View RelatedCreating File Or Folder But Using User Input For Name
Nov 14, 2014File dir = new File("file"); //creates folder named file
File dir1 = new File("file.txt"); //creates file
But I want to take in a file name from user e.g.
BufferedReader br = new BufferedReader(is);
String filename = br.readLine( );
File dir = new File(filename + ".txt");
its expecting a string literal is there a way round it to take a string???
Creating Matrices With User-given Row And Column Size
Sep 15, 2014I am instructed to create a program that reads input from the user and turns it into a desired matrix size (row and column between 0-10). I have written the code for the input window, however I am having trouble with the Event Handler for the JButton in said window. The JButton should read the info (row and column size) and create three new windows. Two of the windows will hold info entered into the matrix by the user, and the third window will have another button that adds the two matrices together and shows the output. I have always had trouble comprehending how to use and implement JButtons. Here's my code thus far.
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.util.*;
public class Matrices implements ActionListener {
private JFrame win;
private JButton button1, button2;
[Code] .....
Creating Playlist From Songs That User Has Entered
May 3, 2015I'm trying to implement a playlist class that creates a playlist from songs that the user has entered. Basically, it'll have the following requirements:
There can be a maximum of 2 playlists.
Each playlist holds a maximum of 3 songs.
Can't be over 12 mins.
Can't be over 10 MB.
Can't use arrays (a real pain).
I'm really struggling with how to even go about this. I'll post majority of my code below, I know a lot of it can be condensed/improved but I'm just trying to focus on functionality at the moment.
Interface class:
public class Interface
{
Scanner console = new Scanner(System.in);
private SongDatabase database = new SongDatabase();
private Playlist playlist = new Playlist();
private int songCount=0;
[Code] .....
In short, the aspects that are relevant to the playlist functionality are the addSongtoPlaylist() method in Interface class, the getSong() method in SongDatabase class and the Playlist class.
Three Different Internet Service Provider Packages - Calculate Customer Monthly Bill
Feb 20, 2011What to do with this JAVA code?
This is the code that I need to do without using the Joptionpane:
An Internet service provider has three different subscription packages for its customers:
Package A: For $9.95 per month 10 hours of access are provided. Additional hours are $2.00 per hour.
Package B: For $13.95 per month 20 hours of access are provided. Additional hours are $1.00 per hour.
Package C: For $19.95 per month unlimited access is provided.
Write a program that calculates a customer's monthly bill. It should ask the user to enter the letter of the package the customer has purchased (A, B, or C) and the number of hours that were used. It should then display the total charges.
This is what I have so far : Cannot use Joptionpaneshowinputdialog
/* A demonstration of how to use Decision Structures
import java.util.Scanner;
/**
This program demonstrates a switch statement.
*/
public static void main(String[] args)
{
char packageLetter;
int hoursUsed;
[Code] ....
Importing Image To Resize
Nov 30, 2014I want to import an image to resize but not sure how to start of.Should I be using the "BufferedImage & ImageIO.read" method or the "paint(Graphics g) { Image img1 = Toolkit.getDefaultToolkit().getImage" method?
View Replies View RelatedImporting Apache Commons?
Feb 18, 2014I've got this annoying error message when trying to import:
import org.apache.commons.codec.binary.Hex.encodeHex;
"Import org.apache.commons.codec cannot be resolved", which after searching seems to be a somewhat common problem. The solution being to go to: FileUpload - Home and download some jar file and add it to the /web-inf/lib folder. yet the error persists even after adding the jar file in "add external jar files" and restarting eclipse.
The jar file I added is called "commons-fileupload-1.3.1.jar" which is the only one I could find in the zip file. I've searched around looking at numerous threads about the issue, several of them sadly several years old, with no success.Surely installing a library to eclipse shouldn't be this complicated?
Importing Libraries To JSP Page?
May 5, 2014I have been working on project (developing web interface for generating dynamic reports)for that i have downloaded dynamic reports library and i want this library to be imported for my project to jsp page on netbeans 7.2 how can i do it?
View Replies View RelatedImporting PDF Attachment From Email Into A Database?
Aug 28, 2014I want to import a PDF file into a database, The PDF will be pulled from an email.
The PDF file must be imported into a specific user's profile.
When the user logs into his profile the file must be visible to that person only.
Importing Math Formula To Java
Sep 1, 2014i am trying to calculate the number of months it takes to pay off a set amount of credit card debt given the following information: principle amount, annual interest rate, and monthly payment. How to import the formula necessary to system.out.print the answer (number of months it takes to pay off debt) ???
View Replies View RelatedImporting Static Members Of A Class
May 11, 2014When importing static members of a class. Why are they only accessible within the constructor of the calling class, and not outside of it? Here's the source code to understand my question.
package Certification;
public class ExamQuestion {
static public int marks ;
static public void print(){
System.out.println(100);
[Code] ....
Creating A System That Will Ask User To Create A File That Will Store To Text File
Mar 9, 2015I am new to java and I am creating a system that will ask the user to create a file that will store to a text file, Once the user created the file I have a class that will let the user input the subject name that has been created, However, I keep on getting this java.util.nosuchelementexception.Here's my code:
public void display_by_name()
{
String id, name,total;
String key[]=new String[30];
String value[]=new String[30];
int i=0;
[code]....
Importing CSV / Reading Data And Have A Count Using Queries
Oct 11, 2014Ok so I know how to import a csv using java. What I'm curious about doing is importing a csv using file chooser, reading the data, sorting the data out by certain parameters, and then outputting a count of each parameter I chose. Say for example I have columns 1,2 and 3. Column 1 has the name, column 2 has the percentage, column 3 has an o'clock time. I want to use queries to sort through the parameters and have a count of each parameter I choose...
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