I'm having trouble completing my homework. The problem:
>Suppose that you want an operation for the ADT list that adds an array of items to the end of the list. The header of the method could be as follows:
public void addAll(T[] items)
>Write an implementation of this method for the class LinearLinkedList
At first this seemed like an easy problem to me. This is the solution I came up with:
public void addAll(T[] items) {
int length = items.length;
for(int i = 0 ; i < length; i++){
this.addLast(items[index]);
}
}
However, one of the requirements for the assignment is that we're not allowed to use the addLast method. how else to insert items to the Linked List without this method. These are the user-defined LinearLinkedList and ListNode classes we made during class:
**LinearLinkedList**
// Linear linked list class
import java.util.NoSuchElementException;
public class LinearLinkedList {
I am trying to create a GUI interface in swing which consists of four classes: a GUI class, which creates a main JPanel, a label, and a JList, which it takes from the second class, a MovesList class that contains a JList and the stuff needed to interface with it. It also has a main class, which basically just creates an object of the GUI class for the main window, and an Other class from which I would like to be able to add an item to the JList. I created methods in the MovesList class to get each component (like getMoveslist, or getMovesListScrollPane), which I then used to create the JList in the GUI class. I also created an addMove method so that I can add an item to the JList from any class through a MovesList object. However, this addMove method only works when called from the GUI or MovesList classes -- it does nothing when I collect from the Other class.
Here is my code:
//Main class public class TestProject { public static void main(String[] args) { GUI mainWindow = new GUI(); mainWindow.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
[Code] ....
When I run this code, I get a window with a JLabel that says "Moves," and a JList that contains five elements -- test 1-test 5, but not a sixth "test from other class." ( using the add move method ) However, when I click on the window, the addMove method is also called, and successfully adds "test 6" to the list.
I was supposed to write a PolyNode class for each node in the LinkedList, and a Polynomial class which is pretty much the list itself.Here is what I've coded so far:
PolyNode class:
public class PolyNode { private int coefficient; private int exponent; private PolyNode next;
[code]....
The only trouble I'm having with this problem is finding a way to add these two polynomials together. My first attempt at it was to use nested while loops to traverse through both polynomial lists, like so:
public Polynomial addPolynomials(Polynomial p1, Polynomial p2) { PolyNode current1 = p1.getFirstNode(); PolyNode current2 = p2.getFirstNode(); int coeff; int expo; Polynomial polySum = new Polynomial();
[code]....
Basically what this method does:
-Check to see if the exponents between two terms are the same -If true, add their coefficients together -Create a new node for the polySum with that coefficient sum and the particular exponent value -At the end, return the polySum list which should be the sum of two polynomials
The problem with this method is it doesnt account for the values that are left behind because their exponents aren't equal to the exponents of the other list. So, the only terms that are getting added into the sum list are the ones that have the same exponent in both of the lists that are being added together.
TL,DR: observe the nodes just below, that is the data each node in the link list contains. How do I iterate through the entire list to reach the last element (H), so I can add an element right after it?
So I have 4 nodes doubly linked with two dummy nodes for head and tail:
Ok, so since the list only contains 8 elements that are not null, its size is actually 8 correct? So now lets say I have an add method that has
add(E item) and inserts the item at the end of the list. So I can get to the last node with tail.previous(), but then how do I iterate to the end so I can add the item after the last item in the list (H). I guess I don't know how you only access one nodes data when that data is an array with empty spaces.
Here is the entire Node code:
Also, I can't just iterate through the whole thing because I am not supposed to. I am supposed to just find the right node and iterate through that only.how to maneuver around a linked list containing nodes where each node contains an array.
/** * Node class that makes up a DoublingList. Feel free to add methods / * constructors / variables you might find useful in here. */ public class Node<E> {
/** * The node that comes after this one in the list
I'm trying to read from a file. we made an array of LinkedList and when I'm reading from the file i get a runtime error "index out of bounce in line 66"
import java.lang.*; import java.util.*; public class HashTester{ LinkedList_t [] hash; LinkedList_t [][] doubleHasher; int size;
Im making a simple code to add an array to a List (the code im referring to is <String> )
import java.util.*; public class L5_ArrayListProgram { public static void main(String[] args){ String[] things = {"lasers","ghouls", "food", "dark"}; List<String>list1 = new ArrayList<String>(); for(String x: things) list1.add(x);
My simple question is - what are the <String> ...<String> for? I understand it makes the list1 variable a string, but why is it made like this? do we usualy use <String> when we need to make a variable a String?
I made my items class and I am storing my item as a String array to list them all and what I want to be able to do is type pickup, have the game read my location and display the items that are avaible to pickup at current location then type the item and store it in my playerInventory. Then, have it check the slot if it is doesn't equal null go to next.
Use a boolean value of 0 = false and 1 = true. then, have it check if the inv array = 1 or 0. if 1 go to next inv. If all are full then, ask player if they would like to replace an item. Use a 2d array for storage for slots and true or false value.
Here is my code
Player.java package com.PenguinGaming; import java.util.Random; import java.util.Scanner; public class Player { public void User(){ Commands commands = new Commands(); Map map = new Map();
I have some class called sorted to sort the linked list through the nodes of the list. and other class to test this ability, i made object of the sort class called "list1" and insert the values to the linked list.
If i make other object called "list2" and want to merge those two lists by using method merge in sort class. And wrote code of
list1.merge(list2);
How can the merge method in sort class know the values of list1 that called it as this object is created in other class.
I managed to retrieve data, and set data in my own ways in which I like. But my problem is, if the file does not contain anything (fully empty), when I try to use my
set("", ""); method, it only sets the last one that is called.
I am trying to make a text based game. the game has been working perfectly setting up the rooms, first couple of commands, and running it. I am now trying to add items to it but every time it try to run the game it returns :
java.lang.NullPointerException at Room.addItem(Room.java:107) at Game.createRooms(Game.java:133) at Game.<init>(Game.java:28) at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
[Code] .....
Here are the classes that matter for this particular situation
import java.util.HashMap; public class Item { private HashMap<String, Item> itemList; private String name; private String itemDescription;
[Code] ....
I know that it is the line
itemList.put(item.getItemName(), new Item(item.getItemName(), item.getItemDescription()));
In the game class that is causing the nullpointer exception i just really cant figure out why that keeps happening and how to add the values correctly....
I need to take the value of what's typed in my JTextField, and once the submit button is clicked, I want to add that string to my JComboBox list items.
Depending which RadioButton they selected, I need to put the team in HOME or AWAY teams, and so on and so on, until they continue clicking submit.
I have the following code. how can items be added to that list?
private List<IComponentNode> comp; interface IAAAView { // returns component with given code or null IComponentNode findComp(String a); // returns component with given renderer or null
So we have an assignment regarding a linked list implementation of a given list interface.
In my list interface, the method contains(T anEntry) is defined.
In the LList implementation, contains is already implemented as part of getting the core methods in.
Now I am being tasked with the following:
Provide a second implementation of the method contains2(T anEntry) that calls a private recursive method
Private boolean contains (T anEntry, Node startNode) that returns whether the list that starts at startNode contains the entry anEntry.
I've written the private recursive method already. That's not an issue (at least not right now).
But what I don't understand is how startNode is supposed to be populated when this private contains method is called from the public contains2 method? contains2 only takes one parameter: anEntry. the private method takes two parameters: anEntry and startNode. How am i supposed to provide startNode when I am calling contains2?
I managed to retrieve data, and set data in my own ways in which I like. But my problem is, if the file does not contain anything (fully empty), when I try to use my
I want to create a program which contains a list with 5 items and a button on the first display. The desired option is chosen from from the list and the button is pressed. On pressing the button it must open a new form which corresponds to the chosen item from the list.
I have this ListInterface class that has operations for my linked list and a LList class. The Llist and ListInterface classes are perfect. My job is to create a driver, or a demo class that showcases these operations. That being said, heres the driver so far:
import java.util.*; public abstract class DriverWilson implements ListInterface { public static void main(String[] args) {
What I'm supposed to do is make a method to insert a set of Tiles to the list,i.e.,a detour(make sure that the inserted detouris compatible with thecurrent path so that the resultingpathdoesnot have any gaps). But I'm confused on how to go about doing it. I was thinking of maybe just adding 1 to the current Node.
import java.io.File; import java.io.FileNotFoundException; import java.util.List; import java.util.Scanner; public class Path { static Tile startTile;
I'm trying to implement an Office class that contains an inner class: WorkerNode. The WorkerNode class has a name attribute (String) and WorkerNode attributes for boss, peer and subordinate. The attributes of Office are manager and current which are WorkerNode references. The manager refers to the entry point of the structure and current is the current node in the structure. For simplicity, i'm going to try to limit it to 3 levels and assume that the names are unique. I've put together a Office class that containing main and provided the code I've worked on so far.
public class Office { public static void main(String[] args) { String name=Input.getString("input the manager's name: "); Office office=new Office(name); int option;
I have made a node class and im trying to implement a sorting method. I must use a selection sort but with specific instructions: "Your method should not need to use the new operator since it is just moving nodes from one list to another( not creating new nodes)
this is my current implementation ..but i am instantiating new object..
public class NodeInt { private int data; private NodeInt next = null; public NodeInt(){} //precondition: //postcondition: public NodeInt(int data, NodeInt next) { this.data = data; this.next = next;
[code]....
edit: this is the part that worked but i had it commented out so i have the previous and current declared above but didnt copy.
Ok here I have a code that generates 1 million random values then converts them to a string then hashcode. I then insert into a linked list and then I want to run through each hash and find it in the linked list timing each run then averaging out the time at the end.
It works great for smaller amounts of numbers it is searching for (fine under 50 thousand searches for the for loop starting at line 24 LinkedListTest.java) but when I try to do the full million searches it gives me "a Exception in thread "main" java.lang.StackOverflowError" at line 158 in List.java. Maybe im getting tired but I cannot figure out why.
// class to represent one node in a list class ListNode< T > { // package access members; List can access these directly T data; // data for this node ListNode< T > nextNode; // reference to the next node in the list
public void add(int d){ listNode l = new listNode (d, null); l.next = first; first= l; } public list Sum2List (list l1, list l2){ //variables int sum;
[Code] .....
But I have a problem in my first listNode where it ll be pointing to null, thus in the sum2List method the program checks the while condition into false and doesn't go through the loop.
if one address point on another address. so set and get methods will be less efficient then an array, but add or remove will be more efficient by a linked list ? a linked list also inherit from queue so if i add an elemnt via "addFirst" function . where its adding the element ? to the right most or left most ? if i have for example :
here [ ] --> [ ] --> [ ] --> [ ] -->[ ] or here
linked list its FIFO so the head will be the right most ?
Edit : its confused me a little bit but i understood now .so it will be at the left most. its actually ordered . not like the stack which is LIFO.
I searched a lot but can't seem to understand the sorting of a SLLNode... I noticed a method called Bubble Sort, I understand how it works, but can't think of a way to implement it to my code..
I'm having some trouble with figuring out how to move along a doubly linked list for an assignment. The program is supposed to be a simple board game simulation. Here is what I have so far:
Space.java:
public class Space { private String name; public Space next; public Space previous; public Space(String name) { this.name = name;
[Code]...
I seem to have been able to get all the other methods working properly, but I am pretty stuck on how to do the movePlayer. Specifically because it is passing an integer, but my objects are of type Space and Boardgame.
