Head Of Multiple Linked Lists All Getting Set To The Same Thing?
Apr 16, 2014
I am creating a chained hash table that uses my own LinkedListclass to handle collisons. Here is where my issue is occuring: I start with an array of LinkedLists, my "hash table", intially set to null. When i wish to add a word, if the desired location is null, I create a new LinkedList, place it in that array index. I then create a new LinkedListNode and set the head of the new LinkedList to the new node.
My issue is occuring here: Whenever I set the head of my new LinkedList to my new LinkedListNode all of my previously created linkedlists also have their head changed to the new node.
My debugger shows that I am truly creating new linkedlists every time. I was afraid each array index was just pointing to a single array, but that is evidently not the issue. Below is all the relevant code
public class SetOfStrings {
private int arraySize;
private LinkedList[] mainArray;
private int totalCount;
//other methods here
public boolean add(String toAdd) {
int hashToAdd = hash(toAdd);
[code]....
SUMMARY: Whenever I set the head of a Linked List to a new node, it changes the head of all my linked lists to point to the same new node
Why do I make private Node<AnyType> next;And why do I have an inner class of Node for a linked list?I had the same topic in C, but there it was somehow easier than in java. Because there you have pointers.
Write a Java function Sum2List that takes two lists L1 and L2 of the same size and returns list L that contains the sum of data inside the corresponding nodes of lists L1 and L2.
ex: L1 = {1,2,3} L2 = {4,5,6} L = {5,7,9}
I do not know how to iterate through two different lists >>
I have used unmarshalling concept to retrieve the data elements... I have to check whether the elements satisfy few regulations when compared with data in Database. So, i thought of grouping the employees depending on EType. I have created a Map with linkedlist of employees. Say Map<String, LinkedList<Employe>>EmpMap=new Map<String, LinkedList<Employe>>();
I have already created a class named Employee which has all the setter and getter methods for employee.
Here am going to take Etype(Employee type) as key and linkedlist(list of employees of certain type) as value. How to iterate these linked lists and place them in my Map.
I have the following code that supposed to perfrom sorting on the linked list using method sort in order usind node concept of Linked List but seems to give inlogic results. the following code tests only the values lower than the first value but i can't manage to sort the data higher than the first entered value;
/* * To change this template, choose Tools | Templates * and open the template in the editor. */
import java.util.*; public class ListNode<T extends Comparable> { ListNode<T> nextNode; T data; public ListNode(T item)
I'm working with Doubly Linked Lists and using Java Generics..
My nodes looks like this: class DNode<E> { DNode<E> previous; DNode<E> next; E element;
//and all methods inside }
My list of Nodes looks like this: class DLL<E>{ private DNode<E> head; private DNode<E> tail; private int size;
[code]....
As you can see, as arguments they get "E o"...I need to write a program, which from the main function asks the users how long is the list, and after they type it's length, I ask them to start typing the elements (integers)...and this is how my main method is written, but I can't seem to make it work, specialy when I call the "insLast" method,I guess it's because the arguments i'm giving to the function...how to read the elements and write them into the list?
public static void main(String[] args) throws IOException { DLL<Integer> lista=new DLL<Integer>(); BufferedReader stdin = new BufferedReader(new InputStreamReader(System.in)); String s = stdin.readLine(); int N = Integer.parseInt(s); s = stdin.readLine(); String[] pomniza = s.split(" "); for (int i = 0; i < N; i++) { lista.instLast(Integer.parseInt(pomniza[i])); }
where the first number is student number and the second is their grade. I need to read this information from a .txt file and dynamically create a new node containing that student's number and mark, and insert it in the correct position in the linked list (in descending order based on grade). So I get that each Node needs to contain two data types, an Int for Student # and a Double for their grade, and I'm pretty sure I've done it correctly with my StudentNode class which can be found in the source code linked above.
But what I don't get it using that class to create Nodes in my main class and then sort them based on their Double grade value WHILE they are being sorted. I just don't understand where to actually put the methods and such that does these things. Apparently I'm supposed to have three classes.
One named StudentNode which is just the node info, which I have done.
The second is called StudentList which is apparently supposed to contain the head of LinkedList and the methods I need? I'm not sure how it ties into StudentNode though.
The third and final is just the main class which I'll use to test it.
Then after all that I need to print out the median mark through a recursive method that isn't allowed to use any loops or call and functions/methods that use loops. The function should return the node in the list which contains the median mark. Secondly, in order to find the median, you need to know how many items in total are in the list. Your recursive function must calculate that number (also recursively); you may not keep track of this count elsewhere your program. Your recursive solution should only examine each node only once, and the depth of the recursion should be equal to the number of nodes in the list.
Here's my current in-progress code.
import java.io.FileNotFoundException; import java.util.Scanner; class StudentNode { private int studentNum; private double grade; private StudentNode next;
[Code] .....
I'm pretty sure the StudentNode class is fine, it's the StudentList class that I'm not sure about. I'm not sure how to add nodes since there isn't a getNext() method in the StudentList class.
I'm not sure if my understanding of PriorityQueues is correct, so I'm trying to check if my reasoning is valid. I'm supposed to compare the Big-O for arrays and linked lists for the following instructions:
Insert 100 objects having the priorities 1, 2, 3, ... , 99, 100 Big-O for Array: __________ Big-O for Linked List: ___________
Insert 100 objects having the priorities 100, 99, 98, ... , 2, 1 Big-O for Array: __________ Big-O for Linked List(Assume no tail reference): ___________
If my understanding is correct, priority queues take in items randomly with no particular order, but they are removed according to the priority of each element. If what I've said is true, wouldn't that mean that inserting any number of objects would be O(1) for both linked lists and arrays? If the PriorityQueue has no particular order, then wouldnt each add() simply insert something to the next array index/linked list node?
I am trying to implement product method below which returns the set representing the Cartesian product of the current set and a given set (the Cartesian product contains all ordered pairs (a, b) where a belongs to the current set, and b belongs to the given set). The product should be a ListSet <Tuple<E>> object where each ordered pair is a Tuple element. (I have a Tuple class which implements an ordered tuple)
What am I trying to do in the product method : Make 2 for loop and inside the for loop make an array of <E> then set the 2 elements of the tuple then again set tuple and add it to arrayList. how to set 2 elements of the tuple and set tuple ??
public class ListSet<E> implements Iterable<E>{ SinglyLinkedList<E> sl; public ListSet(){ sl = new SinglyLinkedList<E>();
How to go through each link item in both lists, and directly link them into the new list in order without using insert()
class Link { public long dData; // data item public Link next; // next link in list // ------------------------------------------------------------- public Link(long dd) // constructor { dData = dd; } // ------------------------------------------------------------- public void displayLink() // display this link { System.out.print(dData + " "); } } // end class Link
okay so it says that java int short and byte variables are the same thing. They take whole numbers. But what is the point of byte and short to even exist if int covers it all? Is the short and byte just for fun?
I am totally new to programming in every way, shape or form, and I'm working my way through the Head First Java book (2nd ed). I have just finished copying the code for the initial BeatBox app, the one starting on page 420. When I try to compile it, I get these errors:
BeatBox.java:36: cannot find symbol symbol : constructor Box(int) location: class Box Box buttonBox = new Box(BoxLayout.Y_AXIS); ^ BeatBox.java:40: cannot find symbol symbol : method add(javax.swing.JButton) location: class Box buttonBox.add(start);
[code]....
I doubt that this is relevant, but I'm running Mac OS X, coding in TextWrangler and compiling with Terminal. Java version is 1.6.0_24.
And the servlet handles the HEAD method in the sense that the doGet() method returns if the method type is HEAD.When I run it, the servlet returns the code returned by the entire doGet() method. This shows that the doGet() method does not realize that it is a HEAD method and it should return back without processing further.The application server is Tomcat 4.0.
I'm currently reading Head First Java and want to use the topics shown in the book while I read it to master them. What are some good projects that can be used to practice all the skills taught in the Head First Java book while I read it?
am trying to Develop a download manager that will improve the downloading process, by splitting big files into different parts, and download each part of the file parallel and then combine them properly Just like JDownloader not really too complex like it though but more like it especially the split download part of it. I was able to get a script from some eBook but that doesn't really solve my problem as it only downloads pause and resumes which is not really what am looking for.
I downloaded this code from Head First Java. But when I tried running it on Eclipse, it gives this error message.
import javax.sound.midi.*; public class MiniMiniMusicApp { // this is the first one public static void main(String[] args) { MiniMiniMusicApp mini = new MiniMiniMusicApp(); mini.play();
[code]....
and this was the error message: Jan 02, 2015 8:10:36 PM java.util.prefs.WindowsPreferences <init>Could not open/create prefs root node Software Java SoftPrefs at root 0x80000002. Windows RegCreateKeyEx(...) returned error code 5.
I am trying to flip a coin 1000 times and make the driver class count the number of times a head and tails appear. However, I am having some trouble trying to figure out the error:
package Week5; import java.util.Random; public class Coin { private int heads; private int tails; private int face;
[Code] ....
I was able to print out the generated numbers, but java will print either heads or tails a thousand times and count that as 1000 and nil for the other probability...
Write a class named FileDisplay with the following methods:
1.) constructor: the class's constructor should take the name of a fil as an arugment. 2.) displayHead: This method should display only the first five lines of the file's contents
Here is the following code I have made so far
import java.io.*; public class FileDisplay { private String filename; public FileDisplay(String Filename) throws IOException
[Code] ....
First, in my constructor I have taken in an argument and used that argument to open up an output file. Meanwhile, I'm trying to work n the displayhead method to print out information and to read data to. I haven't opened up my input file yet, but I'm not understand how can I read a print data to an output file. in
public void displayHead() {FileWriter file=new FileWriter(Filename)}
do I make create another instance of the filewriter class to output data?
In simple words, suppose to I want to display some messages on my output file in the displayhead function. Since I already have opened up the file in the constructor, how do I combine that in this method...
I have i am trying to implement tooltip through javascript, like when we click on an image link tooltip should be displayed and it should have close button/ close image to close that tooltip.like the same way i will have multiple images on page, when ever i click on the images all tooltips should be displayed on the page when ever i want to close that then only it should close through close button on tooltip.can we do it through java script or will go for jquery.
public void myFunc(MyNode n, ArrayList<MyNode> path) { boolean hasChildren = false; path.add(n); int index = path.indexOf(n); ArrayList<MyNode> statefulPath = new ArrayList<MyNode>();
[Code] ....
I have similar code that I stepped through in a debugger. After running the code I found that it built the desired tree, in this case a root node H with left child L and right child P. I want list of lists to contain all paths from root to leaf. I expected [H, L] and [H, P]. I discovered that statefulPath is not stateful; after a recursive stack frame pops, statefulPath still contains n! But that stack frame just popped! I expected to see statefulPath be [H] in the debugger and it was [H, L]! So I later have a list [H,L,P] which I don't want. How do I make the statefulPath list I want for my algorithm?
I'm very new to Java, and I am creating a program that takes multiple user input to create one face. I have a class for the eyes, nose, lips, and headshape. For some reason, my program is not drawing the graphics. ***for question purposes, I have only included my head shape class and my test class****
my "test" class:
import javax.swing.JFrame; import javax.swing.JOptionPane; import javax.swing.JPanel; public class FaceTest { public static void main(String[] args) { String head = JOptionPane.showInputDialog("Would you like a circle, square, rectangle shaped head?: ");
