List<Integer> list = new ArrayList<Integer>();
for (int i = 0; i < 5; i++) {
list.add(i * 3);
}
ListIterator<Integer> listItr = list.listIterator();
System.out.println("Traversing in a forward direction");
[Code] ....
Output:--
Traversing in a forward direction
0 3 6 9 12
Traversing in a backward direction
12 9 6 3 0 425
Why 425 is not showing when we are traversing in a forward direction.
I have a problem with a linked list iterator, my problem is implementing the iterator.remove method given the following code:
package mapsql.util;
import java.util.Iterator;
public class LinkedList<T> implements List<T> {
private class Node implements Position<T> {
T element;
Node next, prev;
public Node(T element) {
this.element = element;
[Code] ....
My homework is a Double Circular Link list and when i write implements Iterator it gives me a an error when I compile it the same for my subset method...
ERRORS :DoublyCircularList.java:55: error: DoublyCircularList.iterator is not abstract and does not override abstract method remove() in Iterator public class iterator implements Iterator<T>
^
Note: DoublyCircularList.java uses unchecked or unsafe operations.
Note: Recompile with -Xlint:unchecked for details.
1 error
import java.util.Iterator;
public class DoublyCircularList<T extends Comparable<T>> extends LinkedList<T>implements Iterable<T>
{
Node<T> first;
int size;
public DoublyCircularList(){
first = null;
size = 0;
[code]....
class Test {
public static void main(String[] args) {
int arr[]={1,2,3,4,5};
int search = 5;
int i=0;
boolean flag=false;
[Code] .....
Above program runs fine.Above in each iteration we have 2 conditions, first to check if iteration number is less then array length and second is to match it with the search integer.I am required to reduce these two conditions and make it one only.Have tried it but no success.
I have to create 3 JLabel for Option, Square and Direction. Well, I did but its not in the right place. It should be in the right Panel but i did change the code so its in panelRight1 but its still not changing? Its somehow not working and no matter how i try to change the position of it, it doesnt change at all.
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class CBallMaze extends JFrame implements ActionListener
{
/**
*
*/
private JMenu[] menu = {
[Code] .....
I have to forward my request to another webApplication using post request parameters. In this case Webaplication-1 need send request using post request params to Webapplication-2 & once Webaaplication-2 receives request it has to process & display output.
For this have tried below 2 options which Servlet API provides.
1. RequestDispatcher : this will used to forward request to another resource within the application.
2. sendRedirect() : this method support doGet() of Servlet.
3. Using HttpClient, which is provided by Apache able to do but it will not displaying Output,It sending back response to Webapplication-1 .
Is there any option which will handover request from one webapplication to another webapplication.
I have normal adress which works, like
localhost/contextPath/foo
In URL rewrite filter I forward that call like
((HttpServletRequest) req).getRequestDispatcher(".....foo1.jsp").forward(req, res);
And it gets there. On that page (foo1.jsp) I have link to original href
<a href="localhost/contextPath/foo">click.</a>
When I click that, in url rewrite filter I get:
String url = ((HttpServletRequest)req).getRequestURL().toString();// http://contextPath/foo/contextPath/foo
String uri = ((HttpServletRequest)req).getRequestURI().toString();// /contextPath/foo/contextPath/foo
which is bad address. How to handle that and why it happens ?
I can't figure out how to complete the for loop for the forward method that needs to calculate each pixel on the path setting it to white, starting at location (x,y) and ending at r.
public class Turtle
{
private static BufferedImage img;
private static int black = 0;
private static int blue = 255; // 2^8-1
private static int green = 65280; //(2^8-1)*2^8
private static int red = 16711680; //(2^8-1)*2^16
private static int white = 16777215; // 2^24-1
private double x,y,theta; // what does a Turtle know?
static // a static initializer list
[code]....
I have a scenario here where the JSF lifecycle is not getting invoked. I have a filter, whose responsibility is to filter only authorized requests.the code of the filter is given below
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
HttpServletRequest httpRequest = (HttpServletRequest)request;
HttpServletResponse httpResponse = (HttpServletResponse)response;
[code]....
now in the else block i am filtering the unauthorized requests, and sending them back to the Login.xhtml page of the application.The problem i am encountering here is that, the images and styles associated with the page are not getting loaded, what i am thinking is that when i am using redirect or forward, the FacesServlet is not getting called, and it is directly going to Login page i.e. no Lifecyle is being called.how to Filter the requests and at same time not lose the styles?
I understand that the following is an example of valid reference in java. I also understand that at class creation, first i and j are initialized to 0. j is then re-initialized to 5, as a result of which i's value is 0 and j's is 5 inside main.
class J
{
static int test() {
return j;
}
static int i = test();
[Code] ....
But why is the same not true for the following ? Why is it that i and j are not initialized to the default value of 0 in this case and gives an illegal forward reference?
class test
{
static int i = j;
static int j=5;
public static void main(String[] args) {
System.out.println(i);
System.out.println(j);
}
}
Why is it legal forward reference when using a method, and illegal when pretty much the same thing is done using a variable ?
I have a scenario here where the JSF lifecycle is not getting invoked. I have a filter, whose responsibility is to filter only authorized requests. The code of the filter is given below
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
HttpServletRequest httpRequest = (HttpServletRequest)request;
HttpServletResponse httpResponse = (HttpServletResponse)response;
[Code] ....
Now in the else block I am filtering the unauthorized requests, and sending them back to the Login.xhtml page of the application.
The problem I am encountering here is that, the images and styles associated with the page are not getting loaded, what i am thinking is that when i am using redirect or forward, the FacesServlet is not getting called, and it is directly going to Login page i.e. no Lifecyle is being called.
Am I right on this?, if so how to Filter the requests and at same time not lose the style?
I need to find out if one array list is a sub-sequence of another. The elements in the first list all need to be in the second list and must be in the same order. So s1<n, t, a> is a sub-sequence of s2<q, n, f, r, t, d, a>, but s1<a, a, t> is not a sub-sequence of s2<a, t, a>. I need to use iterators to go through each list, and I should only go through each list once (since it has to be in the same order) so nested loops don't seem like they would work because it would start at the beginning of one list every time it moved to another element in the outer loop's list.I seem to have an issue where the itr1. next()
is ignored when in an if statement.
My current code just stalls and will never stop running. I've also switched things around and put the not equal check after the if it is equal and it throws a NoSuchElementException.
import dataStructures.*;
public class Subsequence3
{
public static void main(String[] args)
{
ArrayList<Character> s1 = new ArrayList<Character>();
s1.add('n');
s1.add('p');
s1.add('a');
[code]....
I am trying to add the contents of the iterator to an arraylist so I can do other stuff to it, however I am getting an error when I actually try adding it to the list, stating that
"The method add(Map.Entry<String,myObject>) in the type ArrayList<Map.Entry<String,myObject>> is not applicable for the arguments (myObject)"
Here is what I have tried doing:
Iterator<Map.Entry<String, myObject>> iterator = hash.entrySet().iterator();//hash is my HashMap object
ArrayList<Map.Entry<String, myObject>> list = new ArrayList<Map.Entry<String, myObject>>();
while(iterator.hasNext()){
Map.Entry<String, myObject> entry = iterator.next();
list.add(entry.getValue());//error here
}
I am trying to use an iterator instead of a foreach loop to go through a list of inventories to see if a car is rearDrive and count how many are rearDrive but somehow I seem to be missing something that the counter isn't working as expected.
public int howManyAreRearWheelDrive(){
int i = 0;
int counter = 0;
int inventSize = inventory.size()-1;
while(i < inventSize){
boolean wheelDrive = inventory.get(i).getIsRearWheelDrive();
if( wheelDrive == true){
counter++;
}
}
return counter; // returning here doesn't give me anything
}
The Iteratior provides the functionality of traversing and removal which we can achieve through normal for loop and remove() of the data structure.Then, why do we need Iterator explicitly and as an inner class?
View Replies View RelatedWhat does the iterator() method return???it can't return an object of Iterator as it's an interface...
View Replies View RelatedAs part of a homework assignment in my 1st Java Class, I am creating my own Circular Generic LinkedList and Array class. My class uses the Queue Interface Extends Iterable but I am creating my own methods to work with. For the most part, I believe I have been successful in creating the class aside from one method. That method is the Iterator<E> iterator().
/**
* Return a fail-fast iterator, which throw a java.util.ConcurrentModificationException
* if the client modifies the collection (via enqueue(...) or dequeue()) during iteration.
*/
@Override
public Iterator<E> iterator() {
I don't understand how an iterator, let alone a "fail-fast" iterator ties into my project. I've spent hours reading up on a way to imploy my own generic fail-fast iterator but to no avail.
I feel like I could come up with some workable code if I knew what the point is to useing a user-defined, non Java Library iterator is to do.
As well, does throwing a ConcurrentModificationException require a try and catch block?
public class StringTest
{
public static void main(String args[])
{
String s1="hello";
s1=s1.concat("me");
String s2="hellome";
if(s1==s2) System.out.println("s1 and s2 has same referance");
if(s1.equals(s2)) System.out.println("s1 and s2 has same content");
}
}
Output is : s1 and s2 has same content
if after concatenation both string is stored in string pool it will refer to same memory location and other confusion is after any string operation like (concatenation , replace , substring) jvm creates a new string in which memory area..?? Heap or String pool.
I am tring to run LDA to generate some topics from txt files as the following one:
Document1 label1 forest=3.4 tree=5 wood=2.85 hammer=1 colour=1 leaf=1.5
Document2 label2 forest=10 tree=5 wood=2.75 hammer=1 colour=4 leaf=1
Document3 label3 forest=19 tree=0.90 wood=2 hammer=2 colour=9 leaf=4.3
Document4 label4 forest=4 tree=5 wood=10 hammer=1 colour=6 leaf=3
Each numeric value in the file is an indication of the number of occurrences of each feature (e.g., forest, tree) multiplied by a given penalty. To generate instances from such a file, I use the following Java code:
String lineRegex = "^(S*)[s,]*(S*)[s,]*(.*)$";
String dataRegex = "[p{L}([0-9]*.[0-9]+|[0-9]+)_=]+";
InstanceList generateInstances(String dataPath) throws UnsupportedEncodingException, FileNotFoundException {
ArrayList<Pipe> pipeList = new ArrayList<Pipe>();
pipeList.add(new Target2Label());
[Code] .....
I then add the so-generated instances to my model using the instruction model.addInstances(generatedInstances). The resulting output is described below.
It contains errors caused by the instruction model.addInstances(generatedInstances). Debugging my code showed me that the alphabet associated to the model is null. Am I using the wrong iterator?
name: document1
target: label1
input: TokenSequence [forest=3.4 feature(forest)=3.4 span[0..10], tree=5 feature(tree)=5.0 span[11..17], wood=2.85 feature(wood)=2.85 span[18..27], hammer=1 feature(hammer)=1.0 span[28..36], colour=1 feature(colour)=1.0 span[37..45], leaf=1.5 feature(leaf)=1.5 span[46..54]]
Token#0:forest=3.4 feature(forest)=3.4 span[0..10]
[Code] ....
I have the following HashMap:
// 2009
nobelPrizeWinners.put("2009 Physics",
new PrizeWinner[] {new PrizeWinner("Charles K.", "Kao"),
new PrizeWinner("Willard S.", "Boyle"), new PrizeWinner("George S.", "Smith")});
nobelPrizeWinners.put("2009 Chemistry",
new PrizeWinner[] {new PrizeWinner("Venkatraman", "Ramakrishnan"),
[Code] .....
At the moment, my output is:
2008: Chemistry: Osamu Shimomura, Martin Chalfie, Roger Y. Tsien
2008: Economics: Paul Krugman
2008: Literature: Jean-Marie Gustave Le Clézio
2008: Medicine: Harald zur Hausen, Françoise Barré-Sinoussi, Luc Montagnier
2008: Peace: Martti Ahtisaari
[Code] .....
However, I need a blank line between the final entry of 2008 and the first entry of 2009.
I'm not new to java but i'm not able to solve the following issue: I have a class
public class Localizzazioni implements java.io.Serializable {
private <complexType> id;
public getId().......
public setId().....
The complexType is a class defined in the code somewhere. Now I want to access it in another class I have
Set localizzazioni = new HashSet(0);
localizzazioni=opere.getOiLocalizzazioneOperas(); -- this object give an object of tyoe HashSet
for(Object object : localizzazioni) {
object.get......... // i cannot use any method defined in the class Localizzazioni
}
Why I cannot write inside the for object.getId() and using it?? In other word how i can access the element contained in the object?? the object is an iterator of type Localizzazioni . The class Localizzazioni has some method but i cannot use them? why ....
I am writing a Java Swing GUI application on my pc. I have to give this application to my cousin with another pc, where he is not aware of programming. then how can he execute that application? are there any ways of skipping the "javac" and "java" procedures while executing the app on his computer?
I am using win7 x86 and same at my cousin's place. I am also using eclipse-kepler sr1 ide for app development.
Are there any easy ways of automating this "javac" and "java" process(compilation and execution)? something like...scripting?
I have a method "doSomething" which can take a while to be fully executed.
...
boolean bResult = false;
bResult = doSomething();
System.out.println("Result:" + bResult);
...
I would like to be able to stop the method execution after 10 seconds and continue the normal execution of my class. This means:
- If doSomething() is executed in 3 seconds for example, the System.out.println() statement shows the result of the method
- If doSomething() is executed in more than 10 seconds, after 10 seconds the method is stopped and the System.out.println() will always have false as result.
I have got 2 classes in a source file, 1 real class and 1 test class with main() method. While executing with java command which class name should i write - real class or test class???
View Replies View RelatedI have been researching the Iterator and making a class implement iterable. I have seen this example shown below and was wondering how I could change this so that iterable() is not called upon in the main. I would like to be able to make a method that returns an instance of a class that implements the Iterator interface hopefully an inner class. This is because my program will not have a main and will be supplied with a main that includes a new Object with will use the iterator method.
import java.util.*;
public class IteratorDemo {
public static void main(String args[]) {
// Create an array list
ArrayList al = new ArrayList();
// add elements to the array list
al.add("C");
[Code] ....
This is all I have been able to understand from what I want to do. This does not work and this is what I am trying to achieve
public class MyArrayList implements Iterable {
public static final int DEFAULT_SIZE = 5;
public static final int EXPANSION = 5;
private int capacity;
private int size;
private Object[] items;
[Code] ...
I made a check4 application with Java.It correctly works but sometimes the application just stop itself during the execution.I never had a problem like this. The application just stop itself and i can't even quit using the closing button..
View Replies View Related