I am having an issue deleting a node for a tree for one of the cases.The cases for deleting a node are:
1. if its the root set it to null
2. if its a leaf, have its parent point to null
3. if the node you want to delete does not have a right child, have deleted nodes parent point to delted nodes only child
4. find the nodes predecessor(next largest value), have have predecessor's left child be deletes left, and preds right to be deletes right. then have deletes parent point to pred and finally, delete preds old spot (the one that is giving me an issue, I believe)
The pre order of the tree I am currently on is 50 5 4 10 190 100 100 200 190 201
I am trying to delete 190 (which should be the first one)but when I try to print out the list after I delete, I get a stack overflow error when I try printing everything out.I am pretty sure that it has something to do with me hooking up the nodes incorrectly since error occurs for case 4, since it prints out just fine when I deleted previous nodes (like a leaf).Here is my delete method: (note, ignore my determineX and checkOtherHalf methods)
public boolean delete (E item) {
if(root == null){
return false;
else if(item == root){
root = null;
return true;
[code]....
I have confirmed that it is a pointer issue: I need to assign replacements old parents left child to null, to stop it, but idk how.Here is a screen shot of it when I debug it
I've a ArrayList with dogs on, and I've a function that should allow me to delete a dog from the register and if the dog was found it prints "The dog was deleted" and if the dog doesn't exist in the arraylist it should print "the dog couldn't be found".
Everything works perfect until I shall delete a dog that is not first on the list. Then the program shows first "dog was not found" and on the row after "the dog was deleted" if the dog was second on the list. If it was third I will get 2 messages that the dog wasn't found and then that the dog was deleted. I've no clue why it prints both else and if!
public static void taBortHund(){ //Har tar vi bort hund fran listan //System.out.println(hundlista); System.out.print("Vilken hund vill du ta bort? "); String hunden = tangentbord.nextLine(); for (int taBort = 0; taBort<hundlista.size(); taBort++){
ok so for class I'm supposed to Write a class DeleteElements that prints out an array and asks the user which number should be deleted and then deletes that number, if it exists from the array.
The first part tells me to
Step 1 o Start by simply searching the element.
o Pseudocode: -Create an array and populate it with random positive integers. -Print the array to show the user which elements the array contains. -Use a WHILE loop to search the element—a WHILE loop is better than a FOR loop because you can stop when the element is found by using a Boolean value in the loop condition—and also keep track of the location where the element might be found. -If the element is not found, output the error message, “Number not found.” -Otherwise output the message, “Number found at index #.” where # is the index where the element is. -Print out the array.
Example of output: 34 65 12 76 45 39 86 71 67 Number to delete: 76 Number found at index 3
This is what I've got so far but I can't seem to get the "number not found part to print out only once".
public class DeleteElement { public static final int ARR_LENGTH = 10; public static void main(String[] args) { Scanner input = new Scanner(System.in); Random ran = new Random();
[Code] ....
Current output result if value does not exist:
61 89 52 16 20 71 37 91 4 36 Number to delete: 23 Number not found. Number not found. Number not found. Number not found. Number not found. Number not found. Number not found. Number not found. Number not found. Number not found. Current output result if value exists:
97 48 51 22 89 5 42 97 43 96 Number to delete: 89 Number found at index 4
Maybe I'm not understanding the part about the boolean value.
What I want is ..on selecting heading check box...all the below check box should get selected....and clicking on delete button which i will create later on...i want multiple rows to be deleted from database....
Working on my final which is due today, its' and Inventory Program which I have been working on for the last 5 weeks. My Buttons on my GUI Add/Delete doesn't add items to my inventory. I'm not sure exactly what wrong with my code, I'm not getting any error and the Program compiles just fine, I just can get the Items to add of delete.
my Delete button starts on line 281 my Add Button begins on line 319
// /** Purpose:the purpose of this software is to display inputs as wells as the stocks and price of inputs, *as well as display a 5 % restocking fee per dvd and for the entire Invenotry of each object. *adding a GUI to the code. Adding a Previous button to the existing code allowing the user to cycle through *the Inventory list freely. Also adding a graphics logo to page. adding more buttons and allowing program to *save new items added to the inventory. **/
My method below works fine to print a matrix but when it prints every row, it is printing extra 4 white spaces which is not required. How can I delete those extra spaces at the end? when I use
My current lesson in Java is about ArrayLists and I'm having a tough time to understand this bit of code: This exercise is concerned with the problem of deleting a block of items from an ArrayList.
public static void deleteBlock( ArrayList<String> strings, int n ) { for ( int i = 0; i < n; i++ ) { if ( strings.size() > 0 ) strings.remove( i );
My method below works fine to print a matrix but when it prints every row, it is printing extra 4 white spaces which is not required. How can I delete those extra spaces at the end? when I use
I have a program for a phone directory. It needs to add, delete, append, and edit telephone records. I've gotten it to write and search the files. Just need to get it to delete and edit them.
If my file name is MyBigXMLFile.xml it won't delete but if I rename it to mybigxmlfile.xml it will delete. How do you get around the case sensitive issue?
I am following those three tutorials and I have completed it with success.
( [URL] .... ) ( [URL] .... ) ( [URL] .... )
But then, as author haven't implemented removeCountries method I tried to create it. What I did initially was to just add to class Countries this method:
public boolean removeCountry(Country country) { return countries.remove(country); }
But although compiler wasn't complaining it didn't work. Actually it worked last night (before reboot) but not today. Must be some SOAP iterator/binding thing or whatever. Or I thought that it worked but in fact it didn't.
Here are original classes:
//------------------------------- public class Country { String CountryId; String CountryName; public Country() { super();
[Code] ....
I would like to avoid my own iterator as JDeveloper can generate automatically iterators for webservices, but if I can't get it that way, what would be better way to write above mentioned iterator in removeCountry method?
Is there any way to remove object directly with something like this:
co.countries.remove(o); co.removeCountry(country)
using method
// This left unused public boolean removeCountry(Country country) { return countries.remove(country); }
I have a problem with this application , I have a button that allows users to delete entry's from the array list, but i've noticed when i go back and click display entry's the correct entry has not been deleted.....for example if i enter a,1,2 then b,1,2, then c,1,2 in fields, then delete c,1,2 when i actually go to display the data entered a,1,2 will be gone not the one i entered.
So it seems to be deleting the entry at index 0 of the array list no matter what and not the chosen item..Delete Button Code
private void deleteBtnActionPerformed(java.awt.event.ActionEvent evt) { if (numTf.getText().equals("") || nameTf.getText().equals("") || yearTf.getText().equals("")) { JOptionPane.showMessageDialog(null, "All fields must be full"); } else if (count == 0)
I'm working on a GUI Phonebook and need getting a button to work for deleting a contact. I identified the error I get in the Gui class where it says applyDeleteEntry(); on line 106 with comments. The entries are stored in a .txt file which is created for you.
Main class:
import javax.swing.*; import java.awt.*; public class Main{ public static void main(String args[]) throws Exception{ Phonebook mainPhonebook = new Phonebook(); Gui mainGui = new Gui();
I have an add button on my screen to add a new node to tree. So once we click add button a popup comes to provide the new node name and then we press add button and the new node gets added to the tree.So know i want that when ever we add a new node to the tree the value of the new node should get stored in an array at the same time.
I am trying to advance to the next node in my linkedList. Below is what i have so far.
/** * Move forward, so that the current element is now the next element in this sequence. * @param - none * @precondition: * isCurrent() returns true. * @postcondition: * If the current element was already the end element of this sequence (with nothing after it), then there is no longer any current element. * Otherwise, the new element is the element immediately after the original current element. * @exception IllegalStateException * Indicates that there is no current element, so advance may not be called. **/
I am getting errors when I try setting left and right values (which are String types) for my tree.I tried doing something like:
Node node = new Node("Is it human?", null, null); node.getLeft().setNode("Is it Zelda?");//the first left Q node.getRight().setNode("Is it Kirby?");//the first right Q
but that gives me a runtime error of "java.lang.NullPointerException" which points to the line 2. I also tried this:
Node node = new Node("Is it human?", null, null); node.setLeft(setNode("Is it Zelda?"));//the first left Q node.setRight(setNode("Is it Kirby?"));//the first right Q
but that gives me another error, pointing to the setNode for both lines 2 and 3,plus it wouldnt make sense since both setLeft and setRight takes in Node types, not String types.
Here is my Node class:
public class Node { private Node leftPt, rightPt;//left and right pointers for Node private String node, left, right; public Node(String node, Node leftPt, Node rightPt){ this.node = node; this.leftPt = leftPt; this.rightPt = rightPt;
I want to have a button that will include another node beyond the text and image that are part from the Button. This node as example will be a circle that I will change his color from gray to green if the button was pushed.
I try to do this with Background / BackgroundFill with no success
I tried to get access to the Pane / Region of the Button, but I can't find a way to do it.
I have problem with manually (through my java code) selecting items in a JTree. I did Google the problem and found solutions here :
[URL]
This code worked for me only partially. Once I tried selecting deeper nested nodes, I ran into problems. Since my production code is very cluttered I built an example and reproduced my exact problem in it.
It streps through the tree by comparing user objects and finds the target node. Then it calls 'navigateToNode()' which uses the solution discussed in the links above.
This method behaves incosistently:
If you call it with an empty array it will correctly select the root node. The righthand pane shows the text of the selected node. = correct
If you call it with target node 1 it will correctly select node 1. The righthand pane shows the text of the selected node. = correct
If you call it with target node 1.1 it will select node 1.1 but for some reason it is not displayed as marked (no background). The righthand pane shows the text of the selected node. = only partly correct
If you call it with target node A it will run into an exception. Debugging reveals that the selection occurs correclty at first. You can also observe the righthand pane showing that 'A' was selected. But afterwards another TreeselectionEvent is occuring that has a NewLeadSelectionPath of null. I do not know where this second SelectionEvent is triggered from.
This code is run with Java 1.6.0_39 which is also what I will have to use in production.
I have some work where I have to create a binary tree. Anyway I am stuck on one of the classes which has several methods I must fill in! The code is below
The headers for each method are: public Node find (member p1)The method find(Member p1) is used to return the node which contains a particular member. It is a private method because the interface to CabinetTree should not provide direct access to the internal nodes. It makes use of the method Node findNode (Member p1, Node current)
and the next method is : Node findNode(Member p1, Node current) which searches the tree from current node to find a node whose value is equal to the Member p1, i.e. a node in the tree such that p1.equals(current.getMember()) is true. If there is no such node then the method should return null.
public class CabinetTree { private Node head; CabinetTree(Member p1) { head = new Node(p1, null);
