I need a method to do an inorder traversal for the following class
public class TreeNode {
/** the data stored at this node */
private String data;
/** the left child */
private TreeNode left;
[Code] ....
Any link to the accurate explanation of binary trees in java?
View Replies View RelatedI have a question related to trees in Java. The following code is given:
public class BinarySearchTree {
private Node root;
public BinarySearchTree() {
this.root = null;
}
public BinarySearchTree(Node root) {
[Code] ....
The inorder-method is the one that really imports. I have to go through a tree using the Inorder-method. I do understand how this works, however I don't understand how the code fits to the inorder process. I understand the code up to the point where it reaches the most left "root", but then I do not know how to go further. How do I reach the root above then?
I'm trying to build a binary tree using two arrays I'm given, one is inorder and the other is postorder and I have to construct the tree based on that. I understand the strategy I need to use- the last element of the postorder array tells me the root node, and wherever the value of that node occurs in the inorder array is where the tree is split. I can then apply this idea recursively to build the tree. For whatever reason though, I keep getting stack overflows.
Here's what I have so far:
public static class TreeNode {
char val;
TreeNode left;
TreeNode right;
TreeNode(char newVal) {
val = newVal;
[Code] .....
This method uses BFS traversal on a vertex and displays the values. I have worked this out on paper and 2 out of 3 the results from my code match my work on paper. I believe the error is that it prints out 3's adjacent child before 3 itself. I have attached the results I did by hand. Here's the graph and results from my code:
0 1 2 3 4 5
------------
0| 0 1 1 0 0 0
1| 0 0 0 0 0 0
2| 0 0 0 1 0 0
3| 1 0 0 0 0 0
4| 0 0 1 0 0 1
5| 0 1 0 1 0 0
BFS:
5 1 3 0 2
4 2 5 0 3 1 //i think this is wrong. shouldnt it be 4 2 5 3 1 0?
0 1 2 3
Here is my code:
public void bfsTraversal(int vertex){
Queue<Integer> q = new LinkedList<Integer>();
visited[vertex] = 1;//mark vertex as visited
q.add(vertex);
System.out.print(vertex + " ");
[Code] .....
Attached image(s)
I'm facing a problem in controlling the focus traversal mechanism inside a jframe...as i want the focus to travel from top to bottom by pressing tab key regularly , but it travels left to right and then top to bottom through the textfields... The form looks like
textfield1 textfield4
textfield2 textfield5
textfield3
The focus travels from 1 to 4 , 2 to 5 and then rests at 3. but i want it to be like from 1 to 2 to 3 and then 4 and 5....
We are working with LinkedBinarySearchTrees. One of specs on my assignment is to "Using a level-order traversal, create a 2-D display of your trees, using the forward and back slashes as the branch lines. The tree nodes should be spaced proportionally to show the structure of the tree neatly."
View Replies View Relatedthe focus traversal policy (hereafter "tab order") in forms and panels doesn't follow the order in which controls were inserted into the container, but is derived from the position of the components on the form or panel. This is very neat (and probably allows sloppy coders and GUI builders to exist without actually ever thinking about the tab order), except when it isn't. As when you actually want to specify a different component order, for example.
In the following example, I've created a form with two columns of buttons. I want the tab order to go through the first column of buttons, followed by second column of buttons (ie. a column-by-column schema). The default tab order is row-by-row, however, and can be obtained for reference by commenting out the setupFocus() call in the constructor.
I had hoped that the ContainerOrderFocusTraversalPolicy would do the job, but there is a couple of problems (which I've addressed in the setupFocus() method). Firstly, the container itself is part of the focus chain. This at least is easily remediable by calling setFocusable(false), but I don't have to do that with the initial focus traversal policy, so I wonder why I have to do it with this one. The other problem is more pressing, though - the ContainerOrderFocusTraversalPolicy lets me (un)hapilly tab through JLabels. Again, I've fixed this, but the initial policy knows all by itself that it's not a good idea to focus a JLabel. Moreover, I'm afraid there might be other components that do not receive focus with the original policy, but ContainerOrderFocusTraversalPolicy might plod though them.
isn't there some focus traversal policy implementation that I could just set and it would tab through exactly the same components as the original policy, except it would order them according to their order in the container?
Code:
package test;
import java.awt.Component;
import java.awt.ContainerOrderFocusTraversalPolicy;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JLabel;
import javax.swing.SwingUtilities;
[code]...
I want to know is there any way we can call parent class method using child class object without using super keyword in class B in the following program like we can do in c++ by using scoop resolution operator
class A{
public void hello(){
System.out.println("hello");
}
}
class B extends A{
public void hello(){
//super.hello();
System.out.println("hello1");
[code]....
I've 3 classes.
1. Circle
2. GetInputFromUser
3. testCircle
package ABC;
public class Circle {
private double radius;
public double getRadius() {
return radius;
[Code] .....
In the testCircle class, in the line: getRadius = ui1.GetInput();
It's showing the error: The method GetInput(float) in the type GetInputFromUser is not applicable for the arguments ()
And when I do: getRadius = ui1.GetInput(rad);
It's showing the error: rad cannot be resolved
I am just trying to test this array, for a locker combination program that involves classes...but the array is printing out the whacky numbers for the location. When I try to call the method in the main, it does not work. How do I call a method that exist within a class into the main method?
public class locker {
public static void main(String[] args) {
CombinationLock();
[code]....
I am trying to call a private method to another method that are located in the same class.
I am trying to call prepareString to the encode method below.
Java Code:
public class ShiftEncoderDecoder
private String prepareString(String plainText)
{
String preparedString = "";
for(int i = 0 ; i < plainText.length();i++)
if(Character.isAlphabetic(plainText.charAt(i)))
[Code] .....
I am currently working on a dice game. I have a private method called rollDice and it performs the action of rolling two dice. For my project, I need to create another method called playerRolls and I am supposed to invoke the rollDice method in the playerRolls method and perform actions based off of that. My question right now is how do I invoke a method into another method of the same class?
View Replies View Relatedi am having a problem while calling a method..i am having a class
Java Code:
public class MySer implements Runnable {
public void getMessage(String msg)
{
...,
}..,
} mh_sh_highlight_all('java');
i use the above class in another class
[code]....
In the process of creating a new class, I need to move my main method from the class SaveDate to the class DynamicTest. Below I have listed the code of both classes.The objective is to be able to run my program from the DynamicTest Class. I need understanding the process of moving my main method to a different class and creating an Object of a class and calling its method.
public class SaveData {
private static final Map<String, Object> myCachedTreeMap = new TreeMap<String, Object>();
public static final List<String> getLines(final String resourceParam, final Charset charset) throws IOException{
System.out.println("Please get: "+resourceParam);
if (myCachedTreeMap.containsKey(resourceParam) ) {
// Use the cached file, to prevent an additional read.
[Code] ......
Im writing a simple program to understand classes and objects. Basically what I have is a file called Program.java where I have my main method.I have another file called Person.java which I want to use to create Person objects. That person can have a name, email adress, phone number, etc.I put both these files in the same folder.in Program.java my first statement is:
Java Code: import Person.java mh_sh_highlight_all('java');
My problem is that when I compile Program.java i get an error message saying that the package Person.java does not exist.So my question is, when you create a class that you want to use for objects, how do you import that class into your class with the main method so that you can use instances of your other class?
// Add range to Vehicle.
class Vehicle {
int passengers; // number of passengers
int fuelcap; // fuel capacity in gallons
int mpg; // fuel consumption in miles per gallon
// Display the range.
void range() {
System.out.println("Range is " + fuelcap * mpg);
[Code] ....
I'm compiling it in Eclipse and this continues to show in the console display
Minivan can carry 7. Exception in thread "main" java.lang.NoSuchMethodError: Vehicle.range()V
at AddMeth.main(AddMeth.java:34)
How to do draw the original binary tree based on traversal results?
A binary tree has this pre-order traversal result: A,B,D,H,I,E,F,C,G,K,J (TreeNodes) And the same tree gives the following in-order traversal: B,H,I,D,A,C,F,E,K,G,J. Can you draw the tree structure?
I have a program that reads some text, and draws or deletes objects on a JFrame according to what I say. My program works fine for the most part. So whenever I say something like makeStuff(star) in my console, a star is drawn on screen. I kept track of types of objects in an ArrayList, and add and remove certain objects depending on the type of text I input. My problem is when I get to the point when there are no more objects of the same type on screen, meaning I keep clearing objects of the same type until there are no more, when I go to draw another object of the same type, it does not draw the object.
I have two classes, one for my console and one for graphical objects to be drawn. Strangely enough if I call clear twice then I can draw which doesn't make a lot of sense. When going through the debugging everything is working right, including the counters I made, and the amount of objects of the same type have the right amount when they are supposed to. I did find a work around by simply making the object in the console program class instead of calling the draw method from the sandbox class but my console class is probably a 1000 lines of code and is far too big already. I just want to use the draw method from the other class. Here are some revelant lines of code as to what I am trying to do:
Console Class
Java Code:
if (cmd.equals("clear") && arg.equals("star")) { //use a boolean for when this part is done
if (starCounter > 0) {
box.undoStar();
starCounter -= 1;
starNum -= box.getWidth() / 6;
[code]....
Imagine I have a class called Outer that contains a Inner class with a method.
Now there is a second class which wants to call that method:
Java Code: public class Outer {
public Outer() {
Inner inner = new Inner();
[Code].....
I can't get errors of this code I think the problem is that the first method name is the same as the class name and was wondering what the simplest way to fix that is.
class CreditCard{
int transactionNum;
String merchantName;
double charge;
public void CreditCardMethod(int someTransactionNum, String someMerchantName, double someCharge){
[code]...
I use the BlueJ software to develop my programs. I am creating a program which holds two data structures; Array List and Binary Tree. I have created a person class which is used to declare variables containing people, this class also contains a method which prompts the user to input 3 characters of a memorable word. These people are created within the array list and binary tree. This actually works in practice, within the program, but i get an error, and i need the program to contain no errors.
In my binary tree class, i want to call this method.I have attached 4 images to this post, an overview of the classes used, a look at highlighted code which is an attempt at calling a method from the person class, and the method contained within the person class itself. Note that the person class is just called "Person". The 4th image is the error being displayed.
[URL]
I would like to know what does it mean when a method is overridden by a class??Like for example when you append an object value to StringBuilder
View Replies View RelatedI created a BankCommons java file, compiled nd packaged the class file under WEB-INF/classes/com/onlinebank/..I imported the class in the jsp file as <@page import="com.onlinebank.BankCommons.*" % > I ran it through tomcat....the class is being imported..no error there.....but when i try to use one of the method in the class as : BankCommons.update, ...it throws an error that BankCommons cannot be resolved...
View Replies View RelatedI have an admin class that needs to access a method of another class and I'm unsure how to do it.
One of the methods in the admin class (DancerAdmin) accesses a .txt file with information in and each line is to be extracted and is to be created as an object of the Dancer class. The information in each line is to then be used to set the variables in the Dancer class.
To set the values the Dancer class has setter methods which I need to access each time a new object is created while cycling through the .txt file. I'm struggling to access these methods from the DancerAdmin class when I run the relevant method.
The snippet of code I have from the method in DancerAdmin is
while (bufferedScanner.hasNextLine()) {
currentLine = bufferedScanner.nextLine();
lineScanner = new Scanner(currentLine);
lineScanner.useDelimiter(",");
dancer.add(new Dancer());
Dancer.setName(lineScanner.next()); mh_sh_highlight_all('java');
I get an error saying non static method setName cannot be referenced from a static content?
I am calling a method from within a class like so:
xmlWriter.updateFile(environment, doc);
The class is xmlWriter & the method is updateFile
updateFile passes Environment environment (another class) and Document doc (document builder)
but I am unsure about it passing these through the parameters in the method call..is it correct?
Also underneath that method call for the update could I then do another method call for the export method of the file?