How To Create Unmodifiable / Read Only List In Java
Jun 26, 2014How to create a unmodifiable/read-only list in Java?
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How To Create Unmodifiable / Read-only List In Java
Jun 26, 2014I am a java fresher, How to create a unmodifiable/read-only list in Java?
View Replies View RelatedHow To Create Unmodified / Read Only List
Jun 26, 2014How to create a unmodifiable/read-only list in Java?
View Replies View RelatedJava EE SDK :: CDI Bean Cannot Access Public Method Of Unmodifiable Collection
Jan 10, 2010I've got a CDI bean which is a facade for a JPA entity. Such entity has got a many to one relationship with itself and I've got the following method:
public Set<Account> getChildren() {
return this.children;
}
which is called in a JSF/Facelets page:
<h:commandLink action="#{accountController.destroy}" value="#{bundle.ListAccountDestroyLink}" rendered="#{item.children.size() == 0}"/>I then decided to return an unmodifiable set and changed getChildren() accordingly:
public Set<Account> getChildren() {
return Collections.unmodifiableSet(children);
}
The page now reports this error:
java.lang.IllegalAccessException: Class javax.el.BeanELResolver can not access a member of class java.util.Collections$UnmodifiableCollection with modifiers "public"
at sun.reflect.Reflection.ensureMemberAccess(Reflection.java:65)
at java.lang.reflect.Method.invoke(Method.java:588)
[Code] ....
javax.el.BeanELResolver is incorrectly failing because it's trying to invoke the size() method using reflection without correctly taking into account the method visibility (which is indeed invokable programmatically). I'm running NetBeans 6.8, Glassfish 3.0 and jdk1.6.0_17.
Is this a bug in BeanELResolver?
Create A Java Program That Can Read Specific Data Within Csv File To Work Out Averages
Aug 7, 2014i am fairly new to java but have made a few projects so i do know most aspects that would allow me to complete the task its just i have been stuck at the same place now for 2 days.The project is to create a java program that can read specific data within a csv file to work out the averages etc. The csv file is a database of different weather stats . an example of the first 12 months of the csv file is below..
[CSV FILE]
year ,month,average rainfall etc
1946 15.70.616108.131.5
1946 28.23.56111.871
1946 38.82932.9 102.9
1946 414.16.3029.2 150.5
1946 513.96060.7 143.6
[code]...
I know that once the data is indexed i can than use a double to find the average of the 12 specific pieces of data and so on. once this is complete i should than be able to transfer the data to a simple graph.
JSF :: Create A List Or Array Of Child Elements To Feed To Java Bean
Feb 5, 2014I have a project I am currently working on using Primefaces and MySQL. I have a page that will display information queried from the database. I have textfields that will display the data from a given record. But I want to ensure that the displayed data cannot be altered. I decided on disabling the textfields unless the create or edit button were clicked. At which point all textfields will be enabled for editing, and cleared if create button was clicked. I want to push the disabling/enabling of the elements back to a managed bean, but I want to have the bean take in two lists or arrays, one containing all elements by ID and one containing a list of exempt elements. Is there a way I can create a List or Array of the ID's that I can send to the bean? I know little in Javascript and previous attempts to implement it have met with little success.
A short example of the code:
<p:tabView>
<p:tab id=pmDBTab title="PM Database Tab">
<p:panelGrid id="projectInfo">
<p:row id="rowOne">
<p:column id="r1c1" colspan="2">
<p:outputLabel id="searchLabel" for="searchField" value="Search: " style="font-weight: bolder"/>
[Code] ....
I want to create a list that would contain all and another that would contain the exemptions such as searchField, searchCriteria, searchButton, projectList and viewButton. The actual exemption list is far smaller than the list of all children. I have found sources that can disable the elements with a java bean, but I have not been able to find one that would allow me to define those that should and should not be disabled, then vice versa for enabling.
Cannot Read Into Array List
Apr 5, 2014I am creating a hangman game and I want to read in a list of words from a text file, but after the user inputs the name of the text file. I get 'Exception in thread "main" java.lang.NullPointerException'.
Here is the code, where I think the problems lie.
public void runModel(){
ArrayList<String> pirateWordsList = new ArrayList<String>();
System.out.println("What is the name of the file you would like to load? (The file included is called piratewords.txt'");
Scanner in=new Scanner(System.in);
String file=in.next();
load(file);
[Code] ....
The full error message is this:
Exception in thread "main" java.lang.NullPointerException
at uk.ac.aber.dcs.pirate_hangman.Model.load(Model.jav a:108)
at uk.ac.aber.dcs.pirate_hangman.Model.runModel(Model .java:45)
at uk.ac.aber.dcs.pirate_hangman.Main.main(Main.java: 6)
Read String To List (Integer) And Back
Feb 14, 2014I am looking for a good and reliable library to read a string to construct a list of Integers, Doubles, Booleans, etc. This library should be robust enough to handle faulty input from an inexperienced user.
Example:
input: "1, 2, 3, 4"
output List<Integer> [1, 2, 3, 4]
input: "1, 2, 3.6, 4"
output List<Double> [1.0, 2.0, 3.6, 4.0]
input: "true, true, false"
output List<Boolean> [true, true, false]
input: "[1, 2, 3]"
output List<Integer> [1, 2, 3]
input: "(1, 2, 3)"
output List<Integer> [1, 2, 3]
It would be really nice if such a library would already exist.
Searching Array - Read From A File That Is List Of Songs
Oct 10, 2014I have an assignment for my intro class that requires me to read from a file that is a list of songs, their artists, and the year they were released. As seen below, a print line statement prompts the user to enter an artist name, and then it uses a buffered reader to gain input, and then it is supposed to match that input.I realize that this is not a complete statement, but I'm mostly concerned with getting the .indexOf statement to work.Currently it only returns the first object in the array.
for(int i = 0; i < song.length; i++) {
System.out.println("Enter an Artist name");
String input1 = kb.readLine();
if (song[i].getArtist().indexOf(input1) > -1) {
/*tried changing -1 to -2. When I do, it returns the
first array entry, regardless of what I input*/
System.out.println(song[i].toString());
}
}
Use Data Read From File To Create Instances?
Sep 10, 2014"Write a program (save the program as ProductInventory.java) that will read data about 5 products from a text file (Products.txt. The program should use the data read from the file to create instances (objects) of Product.java(Use Product class as a Reference Type)."
I'm yet to discover how I will get the info from the textfile using scanners but I don't know how to "create instances of a reference type".
This is the code of Product.java that came with the exercise.
public class Product {
private String productCode = "";
private String productName = "";
private int quantity;
private String supplierName = "";
private String supplierAddress = "";
private double price;
[Code] .....
By the way, the exercise also required me to use the abstract class ProductLister. To be clearer, the text file is kinda like this:
54643
Rizer Mouse
Mark5s Merchandising
Marquee Mall
4
205.50
23412
Acer Ultrabook
JohnJade Merchandise
Cornal City
2
62200.00
93112
Dell Ultrabook
Octagon Marketing
Cornal City
3
68900.00
22126
Macbook Air Pro
Computerware Services
San Beda, Chad
2
93500.00
EJB / EE :: Create Json From List Data
Dec 16, 2014Create Json from a List's data
View Replies View RelatedHow To Create Withdraw / Deposit Feature So It Cannot Exceed Maximum Limit (read)
Nov 25, 2014So lets say I got maximum of 20 deposit, I want to create a method/function (idk what proper name for it is) so that you cannot deposit more than 20 nor withdraw more than you have in your account, so this function checks your account, if your total is for example 18 and you're trying to deposit 10, it rejects it and doesn't add to your total and pops up with a message, vice versa for withdraw.
This is what I have so far . Not I already have the maximum limit + total feature created just not displayed here
Java Code:
public void depositMoney (int dMoney) {
if(DMoney > 0 ) {
totalMoney = totalMoney + dMoney;
} else {
System.out.println("Please insert money more than 0");
[Code] ....
Swing/AWT/SWT :: Create A Sub Menu For Every List Item In A Jlist
Oct 8, 2014I would like to create a sub menu for every list item in a Jlist. I need the UI like avast interface. If we hover over an list item, its sub menu should be shown. I attempted to put an sub menu but didn't work. Is this possible in Swing?
View Replies View RelatedJSP :: Random List Of Links - Create Web Pages Dynamically
May 1, 2014I have a random list of links whose title I am getting from the database. I'd like to catch one of these links when the user clicks one of them and process it from a single jsp file. Possible?
<ul>
<%
Random random=new Random();
TreeSet<Integer> ts=new TreeSet<Integer>();
for(int i=0;i<8;i++) {
randomInteger=al.get(random.nextInt(al.size()));
ts.add(randomInteger);
[Code] ....
E.g.: when user clicks one of these links, can I dynamically call a web page that fetches information from the click and gets values from a database and insert it on JSP page....
Create Object Of List Type Such As Text File?
Dec 27, 2014I want to create a program where I need to create an object of list type such as text file will contain nos like 1,2,3,4,5 and write into text file and delete the in FIFO order i.e 1,2,3,4,5...how i can achieve to write a program? I tried bt everytime got concurrent modification exception or Array out of bound exception.
View Replies View RelatedJavaFX 2.0 :: Create List Of Entities - Multi-row Tableview?
Apr 10, 2015I would like to create list of entities which is populated by a search function with the data coming from our REST webservice. However I would like it to be multi-line, with the first line being details from the entity itself and the second line buttons for options that can be performed.
So as an example say my entity is People, the first line would contain columns for first name, last name, gender, DOB, etc. The second line would be buttons for "Edit Person", "Print Person details". With the standard TableView I can't see anyway to alternate between one row of data and another row of buttons.
Create Program Which Inherit Stack And Queue From A Linked List Class
Nov 18, 2014I want to create java program in which i want to inherit stack and queue from a linked list class and also make infix to postfix inherit from stack and periority queue from queue class.Ho can i make this program.
View Replies View RelatedRead Input File And Create Output With Anagram For Words In File
Sep 24, 2014Well my code is supposed to ask for an input file and then (ex: input.txt), read the input file and create an output.txt file with the anagram for the words in the file. Also it should be displayed on the screen. However my code doesn't display the anagram on screen or the output file!
Heres is the code:
import java.io.*;
import java.lang.*;
import java.util.*;
/* This program will read a file given by the user, read the words within the file and determine anagrams of the given words. If the file that the user inputs is empty, then the program will output "The input file is empty."
* The program will read the file line by line, counting the total number of words read. If there are more than 50 words, "There are more than 50 words."
* will be printed, and the program will terminate. After each line is read, the words in the line will be separated,punctuation characters will be removed, and upper case characters will be switched to lower case.
* If any word is larger than 12 characters, that word will not be considered in the total amount of words in the file and it will not be sorted.
* After each word is read, the letters will be sorted and stored into an array containing each
* word's 'signature'. After all the words have been read, words will be printed to the output file on the same line based upon their signature.
*/
public class Anagram {
//Creating constants for maximum words in file and maximum chars in word
public static final int MAX_CHARS = 12;
public static final int MAX_WORDS = 50;
[Code] ....
How To Read XML Tag Without Encoding In Java
Nov 16, 2014How to read xml tag <br/> without encoding in java. After encoding it becomes <br>. I dont want to encode it. I already tried CDATA[ and StringEscapeUtils.unescapeXml and StringEscapeUtils.unescapeHtml, but unable to change the decode it.
View Replies View RelatedHow To Read A Name Which Has Spaces In Java
May 2, 2014I do not know how to read a name which has spaces in Java and I wish to learn. The following is my code
import java.util.*;
public class Asking {
public static void main(String []args) {
Scanner reader = new Scanner(System.in);
String [] names = new String[20];
int [] marks = new int[20];
[code]....
Read Or Write In USB Using Java
Sep 30, 2014How can i use java for usb device? I want to read or write in a usb device in java. I've looked for in the web and i didn't find anything!
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Mar 31, 2014I have seen different methods of creating and reading files (specifically text files) in Java. The PrintWriter method or the Formatter with a Scanner to read the file, using a BufferedWriter with a BufferedReader, etc. They will all read/write text files, but from what I understand they do so in different ways. When would it be more beneficial to use a buffered writer than, say, PrintWriter, which is much simpler code-wise? Is there a "best" way to handle i/o in general in Java?
View Replies View RelatedHow To Read Integer And Then String From Java
Feb 28, 2015I am solving a problem in which first my program will ask a number N and then N numbers form the user
suppose:
5
4 3 4 5 6
another
6
3 2 7 8 9 3
and I am using this code
inputValues=new LinkedHashMap<Integer, Integer>();
Scanner in=new Scanner(System.in);
int N=in.nextInt();
String inputString=in.nextLine();
[Code] .....
But its not working as i want . Where is fault?
How To Read Text File In Java
Aug 23, 2014How to read a text file in Java?
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Mar 9, 2009i don't have good grip in java, basically i am a software Tester and rightnow i am automating my application with Selenium (Testing Tool) so i need to write a script in java, so far i Worked with QTP for the same but in that its really easy to Data Driven test with Excel but here i am facing lots of problem. how to read/Write data from excel with java. how can i create input dialog box (like prompt in jscript) ?
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