I am trying to populate a Jlist for information stored on a database. The database contains football club names, but instead of being populated with their names it just has a hexadecimal reference ( Club@183357c4 ) for each club object.
View RepliesI have a LinkedList class that implements a game.
I want to create a list and populate it when a LinkedList object is created .
.
The game constructor takes a word.
How do you populate a LinkedList of any type for example suppose I have a LinkedList of the Integer type, How do I fill it up with 10 integers?
This is the method public void populateMatrices(int [][]mat1, int [][]mat2). I know how to do it for one matrix, but what do we do for the additional matrix? Here is the code I have so far.
for (int row =0; row<mat1.length;row++){
for (int column = 0; column<mat1[row].length;column++){
mat1[row][column]=1 + (int)(Math.random()*5);
I have a method that accepts JSONArray as parameter and returns the values of it as ArrayList Object. My question which of these ways is appropriate in populating the ArrayList object this method populates the arraylist upon creation of object (I don't know what the right term to use, but as netbeans IDE suggest, JSONArray object should be final since it was used in inner class.).
private List<String> getStringList(final JSONArray jsonArr) {
return new ArrayList<String>() {
{
try {
for (int i = 0; i < jsonArr.length(); i++) {
add(jsonArr.getString(i));
}
} catch (JSONException ex) {
ex.printStackTrace();
}
}
};
}
this second method is the usual way of populating collection
private List<String> getStringList(JSONArray jsonArr) {
List<String> strList = new ArrayList<String>();
try {
for (int i = 0; i < jsonArr.length(); i++) {
strList.add(jsonArr.getString(i));
}
} catch (JSONException ex) {
ex.printStackTrace();
}
}
What are the advantages and disadvantages between the two? like which is faster? or which consumed larger memory?
I have been given a task to do, which is to create a memberList and populate it with data. The constructor has been created with me, but I am required to add code to display the memberList. I am also required to creates a method to display members.This is the method I created:
/**
* Populates the list of members.
* Displays the membership numbers and names of library members in ascending membership number order.
* The first member is selected by default.
*/
public void displayMembers()
{
initComponents();
library = new LibraryCoord();
Collection<Member> Member = library.getMembers();
memberList.setListData(Member);
memberList.setSelectedIndex(0);
[code]....
The code below TO DO is mine.What is meant to happen when I run the project is for a GUI form list to show the members of memberList. However, it does not.
I must convert some Java fubction to a plain "Basic", as VB6. The problem I'm facing is this: Suppose I have an array like
Java Code:
private static final int[][] Terms = {
{193, 26, 13},
{183, 29, 14},
{170, 20, 11}
}; // total 659 terms mh_sh_highlight_all('java');
How do I populate the Terms array?
Is it:
Terms[0,0]=193;
Terms[1,0]=26;
Terms[2,0]=13;
Terms[0,1]=183;
Terms[1,1]=29;
Terms[2,1]=14;
Terms[0,2]=170;
Terms[1,2]=20;
Terms[2,2]=11;
?
I'm not sure this is right... Is there a way to automate this process? What if we have arrays like int[][][] Terms? This is terrible... Is there a software tool for this?
I am having a hard time trying to wrap my head around trying to get a couple of columns in a datatable populated with values from a @OneToMany collection. The concept is simple but my brain refuses to grasp it!! I will try to make this brief...
I have several forms built with primefaces 3.5 using NetBeans 8 IDE on a JBoss EAP 6.21 server, and JPA 2.1 annotations. Data is extracted from an Oracle 11 database, which consists of several lookup tables, as well as a primary table and secondary table. Using the EntityManager createQuery method I query the database, which of course returns a resultset. The query grabs all records from the primary, as well as values from 2 specific columns of the secondary database, based on search criteria entered by the user on a primefaces search form. The returned results are then iterated through, this is where I am trying to get the values from the secondary table to populate specific fields in the datatable.Here is the applicable code from the list.xhtml form containing the datatable:
<p:dataTable id="datalist" value="#{foreignPartyController.returnedSearchResults}" var="item"
selectionMode="single" selection="#{foreignPartyController.selected}"
paginator="true"
rowKey="#{item.foreignPartyId}"
rows="30"
rowsPerPageTemplate="10,20,30,40,50"
sortOrder="ascending"
resizableColumns="true"
style="overflow: auto"
[code]....
As odd as the code may look (and I will completely understand anyone cringing as to some of the coding methods I use), specifically with the ui:repeat tags nested inside the datatable tag of the list.xhtml form, I strangely do see the values from the secondary table showing up in the form showing the results in a datatable. However, when the user clicks on a specific record in the returned resultset listed in the datatable, another form is opened and populated with the values from the datatable, but the 2 fields on that form that should be populated with the 2 values I referred to before from the secondary table (i.e. policy1Num and totalPayoutAmt) do not have the values in them.
This is partly because I have those 2 fields in the editable form pointing to the managed bean of the secondary table (code from that bean not shown here), rather than the same "polNum. policy1 Num" and "totPayout.totalPayoutAmt" var I am using in the list.xhtml form. How those values are being successfully returned into the datatable of the list.xhtml form - I happened to "stumble" across the use of the "polNum" and "totPayout" vars with the "policy Payment Collection" list. I do not know how to do the same thing for those 2 fields in the editable form.how a datatable gets populated, specifically with values in a @OneToMany collection,
I am parsing an XML file. i.e.
<people>
<person firstname="John" lastname="Doe" age="50" />
<person firstname="Thomas" lastname="Jefferson" age="260" />
<people>
I have created Person.java with the following attributes:
private String firstName;
private String lastName;
private int age;
My main method parses the XML, loops through each person, and gets the attributes for each.
I need to create instances of my Person class. I could write something like this:
Person person = new Person();
for (int i = 0; i < attributes.getLength; i++) {
if (attribute.getName(i) = "firstname") { person.firstName = attribute.getValue(i);}
if (attribute.getName(i) = "lastname") { person.lastName = attribute.getValue(i); }
if (attribute.getName(i) = "age") { person.age = attribute.getValue(i); }
}
Since my actual XML has quite a few attributes, I would rather do something like this:
Person person = new Person();
for (int i = 0; i < attributes.getLength(); i++) {
person[attribute.getName(i)] = attribute.getValue(i);
}
This doesn't work.
Java Code:
import java.io.*;
import java.util.Scanner;
public class asciiFile {
int height;
int width;
Scanner input;
char[][] poop;
public asciiFile(File f) throws FileNotFoundException{ //constructor
[code]...
The constructor is supposed to take an ASCII file, take the numbers in the file, and populate a 2D array with the numbers in the file.
For some reason, the for loop I use to populate the array works outside of the constructor. When I put it in one of the methods, it runs normally. However, when I keep it in the constructor, I get the following error:
Exception in thread "main" java.lang.NullPointerException
at asciiFile.<init>(asciiFile.java:16)
at main.main(main.java:6)
My code runs and populates an arraylist. However my break statement, while stopping the loop ends up being added to the arraylist. And I'm not sure how to fix this error.
public static void main(String args[]) throws Exception
{
// declaring variables
String input = "";
// creating array list
ArrayList<String> nameList = new ArrayList<String>();
[Code] ....
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 don t know why this throw a nullpointerexception. i want to add rows from mysql database to my jlist, this is my method populateJlist().
public void populateJlist() throws SQLException {
conn= DriverManager.getConnection("jdbc:mysql://localhost:3306/agenda","root","");
DefaultListModel m = new DefaultListModel();
statement=conn.prepareStatement("SELECT *FROM apunte");
rs=statement.executeQuery();
String itemCode;
[code]...
Can I use Jlist instead of Jtable for showing database table data (select * from employee) in my code?
View Replies View RelatedI currently have some code using a JFrame. I am trying to access the items in a JList to save them in a TXT file. For this, I am using a "for" loop. The problem is, is that when I try to access the list items, I can't access them. The way I am trying to access the items is by using:
Java Code: listRight.getModel().getSize(); mh_sh_highlight_all('java');
BUT, I can't seem to get this to work. I tried to place this for loop everywhere and I can't access it. I tried accessing it under "public class Window", "private JFrame frmPcPartBuilder", "public static void main(String[] args)", "public void Initialize()" and I can't seem to access the JList. I basically have a save button that saves the list to a text file and the code I am trying to write is called by this button.
Java Code: package com.cooksys.assessment;
import java.awt.EventQueue;
import javax.swing.DefaultListModel;
import javax.swing.JFrame;
import javax.swing.JButton;
[code]....
I have a empty JList in which I hit a button LOAD DATA which should load all the data. but once I load data i try to fill in the List but I keep getting errors.
String[] aos = new String[itrList.size()];
itrList.toArray(aos);
//JList listFAIL = new JList(aos);
//list = new JList(itrList.toArray());
//list.removeAll();
list.setListData(aos);
JScrollPane s = new JScrollPane(list);
I have tried doing setListData and i get a error;
And if i do new Jlist it doesn't change the data.
The List does fill as i have a checker for that.
I'm currently in the process of creating a shopping cart simulation. The main GUI consists of two lists, one is a list of the inventory. (products stored within a .dat file which is automatically loaded upon launch) The other is blank and is to model my shopping basket. The idea is to be able to scan items from my inventory into the checkout basket. As this is happening i want a text field i created to dynamically update with the cost of all the items in the basket.
Below is the method for my scan button, which is supposed to perform the above :
public void actionPerformed(ActionEvent evt) {
//Get the newly added list values.
JList list = productList.getSelectedValuesList();
double totalAddedValue = 0.0;
double oldCartValue = 0.0;
[code]...
I was programming a crossword in java and needed to hava a list of words from where to choose in case i wanted to fill my generated crossword but I don't know how to upload that txt dictionary in the first place.
View Replies View RelatedI am currently creating a Twitter Application within Java Swing using JSON. I have the JList populating with Home feeds but i also want to get Images displaying next to the Text ...
currently all i am getting is [URL] ....
So a am able to get the URL Link but getting that to a Image seems to be the problem
/ArrayLists
final ArrayList<String> TweetArray = new ArrayList<String>(); //Array List for Users Tweets..
final static ArrayList<String> incomingTweets = new ArrayList<String>(); //ArrayList for Incoming Tweets.
ArrayList<String> arrayImages = new ArrayList<String>();//ArrayList for incoming Tweet Profile Images
private Map<String, ImageIcon> imageMap;
[Code] ....
how to add values from Jtextbox(name) to JList and display the selected values from Jlist.
import java.awt.*;
import java.awt.event.*;
import java.awt.Color;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.border.*;
import javax.swing.DefaultListModel;
[Code] ....
is there a good way to change the color of a JList item that isn't selected? I'm throwing my hand at building a client/server chat app and on the client side, I need to highlight the name of the person (which is in a JList) who has sent a message to the client GUI.
View Replies View RelatedI am currently writing a chess application in Java swing. For the GUI part, I have one MainWindow class, and one ChessBoard class. The MainWindow has a main panel, in which is contained 1) a panel containing the chessboard from the chessboard class (a grid layout array of 64 JLabels), 2) a JLabel status bar, and 3) a JList to hold the moves of the game. I have a movePiece method in the chessboard class, which I would like to add the move and question to the moves list, which is contained in the main window class.
However, since JList is some special type, I can't make it static ( that gives me an error ). I also tried creating a method in the main window class to add a move to the list, which I would then access via the chessboard class. However, I can't make the method static, because it is referencing a non-static variable ( the JList ), and since the Main window class already has an object of the chessboard class, trying to create a main window object in the chessboard class creates a stack overflow error.
I am able to update the array holding the items but I don't know how to refresh the JList to include all the new items in the array.
Code for GUI:
import java.awt.ScrollPane;
import java.awt.event.ActionListener;
import javax.swing.*;
public class ListView extends JFrame{
HobbyList stuff = new HobbyList();
[Code] .....
I am trying to use the JList to display a list of students. Now, each student has a first name, last name and course taken. each courses taken by the student has its' own name, level and idNumber. For now, I am just trying to create my own custom JList model for the students. I have the custom model as well as the button event calling it. Unfortunately, when I click the button to display the student info added, the component is NOT fired up!..
I am not sure what I have done wrong regarding creating the component because I can display the information on the console and the list contains everything I have added but just to display it on the component is NOT working. I have broken the codes into sub classes, you can add the classes to the same package or create sub packages to insert individual classes.
The student class
public class Student {
private String studentName;
private String studentID ;
public String getStudentName(){
return studentName;
[Code] ....
I have a program I am creating in Eclipse. In my JFrame window, I am adding a JList object that I want to load with an EnumMap that I have created in a separate 'enum' class.
In my JFrame, I have a method called 'loadJList()' in which I want to iterate through the EnumMap and load the keys & values.
Here's what I've tried
In my EnumMap class, I've done the following ...
Java Code:
public enum MyEnumMap {
.....//created map values & keys, getter() and setter()
public Enum<MyEnumMap> getEnum() {
return this;
}
} mh_sh_highlight_all('java');
I imported my EnumMap program in my JFrame program and tried something like ...
Java Code:
public void loadJList() {
for(Enum<?> e: myEnumMap.values()) {
list.add ....
}
} mh_sh_highlight_all('java');
Which does not work. I've scoured the internet a bit but sources on EnumMap are limited, at least ones I can understand (first time trying to use this).
I also need to elaborate on the key of the EnumMap (they are cities, I'd like to add the state or country). For example
LASVEGAS, 749.99
I would want displayed as
Las Vegas, Nevada .... 749.99
My ultimate goal here is to access my EnumMap in my JFrame program to dynamically load a JList object.
I know there was a change in the later versions of Java where the C++ equivalent of a <template type> was added. Unfortunately the change has 'broken' my older code. If I have a JList and I want to add elements to it then now I should specify the type e.g., the list will store Strings. When I do this and then add data to the list (or actually the list model) the code is ''fixed". However if after adding those new elements to the list I later need to add more elements, which isn't unreasonable for a list...to have elements added dynamically at run time then I again get the same compiler error message that I haven't correctly specified the type:
// Error message during compilation
Note: Driver.java uses unchecked or unsafe operations.
Note: Recompile with -Xlint:unchecked for details.
// My code
// Problem here: I try to add new elements to the list. It's the very last line of the method that results in the error. I tried various things such as:
// model.addElement(<String> s);
// but so far nothing has worked. How do I add new elements to the list (model)?
public static void m2(JList <String> list)
{
String s;
int i;
String [] array = new String[10];
[Code] ....
// Code is OK: Create the array of strings to add to constructor of the JList
public static String[] m1(){ String s;
int i;
String [] array = new String[10];
for (i = 0; i < 5; i++)
array[i] = i + "*"; return(array);
[Code] ....
// The change I had to make when compiling under the newer version of Java to indicate that the list would store strings
// Things are okay here now but then when I try to add new elements to the model via method 'm2' that's where I get the compiler error
I have an addressBook GUI where I have a JList that populates with the contacts names, and once I double click a contacts name I'm wanting to fill the textfields with the contacts corresponding data.
ex) ContactType: Family (enum), Name: Zoidberg, Address: 111 Space Drive, City: New York City, etc...
I've got it to where I select open from the JMenu, it populates the JList, but once I select a contacts name, all the textfields are populated, but only with the contacts name
ex) Name: Zoidberg, Address: Zoidberg, City: Zoidberg, etc....
What am i doing wrong here, and how can i fix it to where it fills out the correct data?
Here's my code so far:
public class AddressBookGUI extends JFrame {
private final int WIDTH = 450;
private final int HEIGHT = 300;
private JLabel currentlySelected;
private JTextField contactTypeTextField;
[code]...
I'm certain the logic is messed up near the end where i set all text fields to the index, because no matter what field i want to fill it's at it's going to set it to whatever index I select, but I don't know how to fix it.