Java - Allocate Whole Object To One Complex Number
Jul 6, 2014Java has not structures, I must allocate whole object to one complex number?
Java has complex numbers handling, classes for complex?
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Deleting Complex Object In Java List
Sep 3, 2014I 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);
}
from class Countries?
Parameters should be set by web service iterator.
Complex Number Calculations
Jan 25, 2014A complex number is defined as z=a+i*b, where a is the real part, and b is the imaginary part. In other words, in order to define a complex number, we need the two floating numbers a and b. Write methods that perform for each of the following operations with complex numbers z1 = a1 + i*b1, and z2 = a2 + i*b2:
Addition: z1 + z2=(a1+a2) + i*(b1+b2)
Subtraction: z1 - z2=(a1-a2) + i*(b1-b2)
Multiplication: z1*z2 = (a1*a2 - b1*b2) + i*(a1*b2 + b1*a2)
Division: z1/z2 = (a1*a2 +b1*b2)/(a2^2 + b2^2) + i*(b1*a2 - a1*b2)/(a2^2 + b2^2)
Create a test program that asks for the real and imaginary parts of two complex numbers from the user, and displays the results of the four operations, writing the formula as shown above, and replacing the a1, a2, b1 and b2 with the numbers entered by the user.The professor used the incorrect complex number equations and has notified the students of his error. I have run into a few problems thus far.
1. I'm not sure how to use floating numbers with the Math.pow(double, double) function, since its requires doubles!? So instead of using floating numbers, I've knowingly switched them all to double in order to see if the code itself is working properly for the purposes of this forum. Is there a way that I can modify this function so that it will work for floating numbers?
2. Regarding the division method, an error stating that c and d have not been initialized and I'm not sure how to change it because the other calculation methods work fine. Why do I need to initialize c and d in the division method and not the others?
3. Am I on the right path? I have surfed the web to see how others completed the program and they all appear very different than mine...
package program5;
import java.util.Scanner;
public class Program5 {
static double a, b, c, d;
static double i = Math.pow(-1,1/2);
[code]...
How To Update To Allocate Memory In Windows Side
Sep 12, 2014i am running unix scp command as below using Runtime.getRuntime.exec();
scp -P10022 -i /home/.ssh/id_ds 2937_filename.xls Username@hostname
following is the syntax in java:
final Runtime r=Runtime.getRuntime(0;
final String[] arg={ "/bin/sh","-c",command};
final Process process=r.exec(arg);
i am getting followin error java.io.IOException: cannot run program "/bin/sh: java.io.IOException: error=12, Cannot allocate memory
what i need to update to allocate memory in windows side.
How Do Memory Allocate Space For Objects Or Variables
Sep 1, 2014I'm new to programming and I would just like to know what happens inside the memory once you run a java application. How do the memory allocate space for your objects or variables? Where does it start?does it start in memory location 1 first when I create my first variable or object? What is the use of variables and how is it used by the memory?Also if I create a variable named String s1 then I created another variable again named s1= "myString" Did I create a new object or I just edited the value of the s1 variable??
And if I create a variable int num1 = 10 then I created another variable int num1 = 12 did I create another one or I just edited the num1 variable?? Also how much memory would an object have? Does it depend on how many primitives objects like arrays or strings it have?Also I want to develop 3D games also, in the future is Java going to be great as I know machines in the future will have massive amounts of RAM and the JVM will be better...
Adding Into A Complex Array?
May 26, 2015I have a main class:
Java Code:
public class Main {
public static void main(String[] args) {
Player[] playerList = new Player[] {new Player("Daniel", 3, 3, 2, 1, 1, 3),new Player ("Player2", 2, 4, 1, 6, 3, 2)};
System.out.println(Player.getPlayer());
}
} mh_sh_highlight_all('java');
[code]....
and whenever I run it, it prints out the last player, so I was wondering how to identify them separately, but still use the array, as (I believe) it is the most efficient way.
Complex Formatting Within A Text Field
Apr 30, 2015I'm trying to figure out a good way to allow my users to have some formatting options within a text box in my application. Ultimately, they need to be able to have text that is alternating between two separate fonts, and ideally could have both italicized and bolded words as well.
View Replies View RelatedComplex Numbers - Converting Syntax?
Mar 17, 2015Convert to following sysntax (from Matlab) having complex nos.
real((413000*atan((T^(1/2)*((4130000*V*1i)/(139*T^(1/2)) + (413000*1i)/T^(1/2)))/413000)*1i)/(139*T^(1/2)))
Complex Math Functions With A Simple Web Page?
Feb 4, 2015I am a 3rd year electrical engineer and I am working on a project on solar cell design in the developing world.For my project I am looking to create a very simple web page which can be used by people in the developing world to determine whether a photo voltaic system is suitable to their needs.
For this I want to have simple boxes where a user can input numbers and I used complex calculations to return values (a lot of trigonometric functions etc.), the values then should have the opportunity to be altered to the users digression. This will create a solar model.
For the load aspect of it I am looking to have drop down boxes for a number of components which the user can select and will have a numerical value in Watts which will sum to give total load on system. Ideally I would like to show this graphically in a pie chart showing how much energy each component is taking to give the option to remove.
I am also creating a statistical model which determines the likelihood of having no sunlight on a given day which looks at the solar output, battery capacity and load on the system and will return reliability of the system - this has not been completed but should be shortly.
Aim is to keep web page as simple as possible as unskilled computer users may want to use it.
JavaFX 2.0 :: Synchronize Model Representing Complex UI Composite With FlowPane Backing List
Aug 26, 2014What is the best way to synchronize a Model representing a complex UI composite w/ a FlowPane's backing list?
Currently I have a change listener on the Model. Upon an add I create a new UI composite and manually add it to the FlowPane's backing list via flowPane.getChildren().add(). Similarly if there is a remove, I iterate over the FlowPane's children, grab the right Node, and remove it. Similarly, if there is a modification detected, I iterate over the FlowPane's children, grab the right Node, remove it, recreate the UI composite, and re-add it to the list. I also need the list to be sorted, so I implemented a UIComposite comparator and call FXCollections.sort() on the FlowPane's backing list. I feel like that is hacky, but it works. It would be cool if I could maintain sort order in my model somehow and have that automatically propogated to the FlowPane's list.
I am correct in assuming that there is no way to have a complex binding in between an ObservableList<CompositeViewModel> and the FlowPane's backing list (ObservableList<T>)?
Some kind of translator that could create a new UIComposite whenever there is a new CompositeViewModel added to the Model list.
Swing/AWT/SWT :: Using Same Cell Renderer Object For A Number Of Cells?
May 28, 2014I have a number of cells which are Dates and need to have them appear in the same format. The samples I have seen usually create a new cell renderer object for each cell, even if its the same type. Since I have a number of Date cells I thought it best to use a single object for each of the date cells, but after seeing the different samples I am wondering if there is something I may be missing where using the same cell renderer object could potentially be an issue.
View Replies View RelatedJava Lotto - Randomly Generate Five-digit Number And Prompts User To Enter Five-digit Number
Sep 25, 20141. Write a Java program that randomly generates a five-digit lottery number and prompts the user to enter a five-digit number. Each digit in the number is in the range between 0~9. The program should determine which prize the user wins according to the following rule:
- The user wins the first prize if the user input matches all five digits in the lottery number in exact order.
-The user wins the second prize if the user input matches any four digits in the lottery number in exact positions.
-The user wins the third prize if the user input matches any three digits in the lottery number in its exact position.
-The user wins the fourth prize if the user input matches any two digits in the lottery number in its exact position.
- The user wins the fifth prize if the user input matches any one digit in the lottery number in its exact position.here is my code. I have tried replacing the && statements with || and it always returns either case 1 or case default.
import java.util.Scanner;
import java.util.Random;
class Hw5 {
static int getPrize(int g1, int g2, int g3, int g4, int g5,
int u1, int u2, int u3, int u4, int u5) {
[code]...
Simple Data Classes - Serialize More Complex Data Structure
Oct 6, 2014I have written several simple data classes that I serialized manually by converting to text. At this point I need to serialize a more complex data structure. which will include lists of the simpler elements. Can serialize store and reconstitute this type of structure automatically or do I need to do this one manually as well? Consider the pseudocode below for a clarification of my question;
Java Code:
Class Hops{
String Name;
float Alpha Acid;
float Beta Acid;
};
Class Malt{
String Name;
float extract;
};
Class Recipie{
String Name;
CList HopList;
CList MaltList;
};
CList RecipieList; mh_sh_highlight_all('java');
I read the article on Serialization presented at tutorial point, but the example only showed a simple class, not lists of class members. What I want to do is serialize RecipieList, which consists of a CList of Recipies, which in turn consist of CLists of various ingredients.
Equals Method - Take Object Reference And Return True If Given Object Equals This Object
Mar 28, 2014Create an equals method that takes an object reference and returns true if the given object equals this object.
Hint: You'll need 'instanceof' and cast to a (Geocache)
So far I have:
public boolean equals(Object O){
if(O instanceof Geocache){
Geocache j=(Geocache) O;
if (this.equals(j)) //I know this is wrong... but I can't figure it out
return true;
}
else return false;
}
I think I have it correct up to the casting but I don't understand what I'm suppose to do with the this.equals(). Also I'm getting an error that I'm not returning a boolean... I get this all the time in other problems. I don't get why since I have to instances of returning booleans in this. "returns true if the given object equals this object" makes no sense to me. I assume the given object, in my case, is 'O'. What is 'this' object referring to?
Want To Know Size Of Object In Java
Mar 11, 2015class Father
{
public int a=5;
private int b=10;
[code]...
what is the size of obj from above code?
Moving Object In Java?
Feb 21, 2014Basically I have a program that paints a simple object image. There are 5 of these objects altogether and different classes and methods have been set up to do this and this works correctly. The program currently also asks the user if they would like to change the colour of this object shape, and which shape they would like to change (user inputs a number 1-5) then the program will change the colour of this shape.
But the new task is for the user to input a number (1-5) to which shape they would like to MOVE position of. Hhow this would be done? Would there need to be different methods for changePositionX, changePositionY? The user needs to input the X and Y co ordinates and then this will move the selected shape to its NEW position in the current JFRAME.
Java - Cannot Deserialize Object
Feb 12, 2015I can't deserialize my object, program is exited with crash.
See attached file.
How Many Ways To Create Object In Java
Mar 21, 2014How many ways to create an object in java ?
View Replies View RelatedJSP :: Transferring Object To Java Class
Mar 28, 2014I have a servlet that generate a list of objects named "Alerte". I display this list in my jsp and I want the user to be able to delete one of them by clicking on it. Data are stored on Google Datastore. My problem is that I don't know how to pass the current object from the loop of my JSP page to my java class.
<%
List<Alerte> alertes = (List<Alerte>) request.getAttribute("alertes");
%>
<c:forEach var="alerte" items="${alertes}" >
<table>
<tr>
<td>Name:</td>
<td>${alerte.name}</td>
[Code] .....
Servlets :: Create Corresponding Java Object?
Sep 18, 2014I get an json from http request. I want to create a corresponding Java object.
is there any automated mapping? Something called pojo or something else?
Java Object Stored In Array?
Apr 8, 2014I have been having trouble with a recent hw assignment requiring us to sort user defined data types in an array. so far, i have implemented the sorting algorithms correctly but i cant seem to store a string and an integer together. I have an employee class
[public class employee {
private String Name;
private int IdNumber;
public employee(int IdNumber,String Name){
this.Name=Name;
this.IdNumber=IdNumber;}
[Code] .....
And in my app, i create a employee object-----> employee john=new employee(1020, "John");
How can I prompt my insert method to take in employee id and string name together?
Create A Balloon Object In Java
Sep 19, 2014Programming Assignment #2
(Using an Existing Class: Creating Objects and Calling Accessor and Mutator Methods)
I. The Assignment
This assignment is to write a "test" class (aka: a "driver" class or "client code") that uses the class Balloon.java, available on the class web page.
To use the Balloon class, download it and store it in the src folder of your NetBeans project. Make sure you save it as Balloon.java.
The best way to learn how to use the Balloon class or any other Java class, for that matter - is to consult the documentation, Balloon.html (online). You can also read the javadoc comments that appear just above the class declaration and above each method declaration, which explain what each method does, what the method's parameters are, and what value if any - is returned by the method. The html support pages are generated from these comments.
-Review declaring variables, creating objects, calling methods that return a value vs. void methods, and accessor and mutator methods before beginning. To receive credit for this assignment, you must not modify the Balloon class in any way!
II. Your BalloonTester Class
Your BalloonTester class will have only a single method "main" and will perform each of the following operations, in the exact order listed below. Each operation may be done in one or two statements. Make sure you follow directions faithfully, and note that once you have done step 3, you can copy and paste it to do steps 6, 9, and 12.
1.Create a Balloon object with a name of your own choosing and an altitude of 100 meters.
2.Create a second Balloon object with a name of your own choosing, and specify an initial altitude of -100 meters.
3.Call the accessor methods of the Balloon class to get the name and altitude of each Balloon object. Print the data, one object per line.
4.Make the object you created in step 1 ascend to an altitude of 250 meters.
5.Call the adjustAltitude method to increase the altitude of the object you created in step 2 by 150 meters.
6.Call the accessor methods of the Balloon class to get the name and altitude of each object. Print the data, one object per line.
7.Call the adjustAltitude method to decrease the altitude of the object you created in step 1 by 150 meters.
8.Make the object you created in step 2 descend to the same altitude as the other object. You may assume that the other object is at a lower altitude.
To get credit for step 8., the statement(s) you write must always work, regardless of the actual altitude of the second object. It cannot depend on you knowing the altitude of the second object, but must utilize the fact that the object knows its own altitude. In other words, if you use a literal in any way to set the altitude, it is not correct.
9.Call the accessor methods to get the name and altitude of each object. Print the data, one object per line.
10.Move the object you created in step 1 to an altitude that is four times its current altitude. As in step 8, the statement(s) you write must work for any altitude and may not depend on you figuring out the new altitude beforehand.
11.Attempt to move the object you created in step 2 to an altitude that is 150 meters below its current altitude.
12.Call the accessor methods to get the name and altitude of each object. Print the data, one object per line.
and this is the Balloon.java given:
// File: Balloon2.java
// Modified Balloon class has overloaded constructors
/**
* A class to represent a hot-air balloon. Balloon objects have a name and an altitude.
*/
public class Balloon2
{
// instance variables
private String name ; // name of the balloon
private int altitude; // altitude (height) of balloon in meters
[Code] ....
Convert Java Object Using JAXB To XML
Nov 7, 2014I am suppose to have a method called save() which should marshall the list of computer parts in the right panel to an XML file. In reverse, another method called load() that should unmarshall the saved XML file back into an object. So basically, the Save event will call save() method and save the list of parts in the right panel to an XML file. The Load event should clear the right panel, and call load() method. When load() is called, it should display the unmarshalled data in the right panel. I got "Exit" to work.
I'm having hard time figuring out the "Load" and "Save" parts though.
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class PCParts implements ActionListener{
[code]...
How To Prevent Java From Creating Object
Mar 6, 2014I just want to ask about a kind inheritance.Let say I have an interface MachineCode.I also have different classes, Binary, Hex and Octal that implements MachineCode
Question: How can I prevent java to create an Object like this:
Binary bin = new Binary();
Hex hex = new Hex();
Octal octal = new Octal();
those declaration above must be compile error,
I want to create Objects of Binary, Hex, and Octal this way:
MachineCode bin = new Binary();
MachineCode hex = new Hex();
MachineCode octal = new Octal();
Object Level Locking In Java Threads
Apr 16, 2014I know that below code would put a lock on current instance of DemoClass, What I am not sure of is the role of lock on Object Class in second example. How does below works - Is it putting a lock on Object Class? If yes how will putting a lock on Object? I mean, locking DemoClass ensure no two threads access it concurrently, how does this apply to Object class?
private final Object lock = new Object();
synchronized (lock)
public class DemoClass
{
public void demoMethod(){
synchronized (this)
[code]....
Java Object Declaration Beyond Common Idiom
Feb 5, 2015when a new object is created in Java it follows the idiom:
Object obj = new Object();
where the Object() constructor matches the object type Object.
But what if it doesn't? I understand from the Oracle Docs on creating objects and polymorphism that the constructor must be in that object's class or one of its subclasses. However, suppose we wanted to declare a new stack. My first instinct would be:
Stack s1 = new Stack();
But I assume it's valid to do it this way, too:
Object s2 = new Stack(); // Is there a difference here? What are we really saying about s2? I'm guessing s2 is simply an empty stack, but only has access to the Object class methods? I'm not sure why someone would ever do this, but I want to solidify my understanding of the Java hierarchy. Are there really any circumstances where someone would use a subclass's constructor when creating a new object?