Java Design Patterns
May 9, 2015we have been given a scenario to design a system in which we have to make the class diasgrams. however we have to use appropriate patterns that match the scenario.
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Design Patterns And Java Algorithms
Nov 22, 2014I've looked over the concepts of Java programming, tested them in code and i understand most of them. I have a problem when i need to make harder programs , this might be because i dont know design patterns and algorithms.I'm curious what a entry level programmer needs to know to get a job in the field. Right now i was thinking i need to know:
1. The way all big concepts work and most of the keywords.
2. Design patterns.
3. Algorithms.
what i actually need to know for an entry level job and can you tell me which design patterns and algorithms are a must know for that first job. Considering i might have financial problems in the near future this is not a theoretical question, i really need to know what i need to learn in the next 2-3 months to get an entry level job down.
Compare Inheritance And Design Patterns?
Apr 30, 2014Design Patterns are one form of reuse. so is inheritance. what are the similarities and difference between them?
View Replies View RelatedEJB / EE :: Design Patterns - Usage Of Transactions And Exceptions
Feb 3, 2015When it comes to Java EE I see many developers having trouble with the usage of transactions and exceptions and when to use what.
I see a full chapter of RESTful Web Services, but do you also relate these Web Services to their counterparts (SOAP Web Services)?
JSP / JSTL :: What Is The Difference Between Design Patterns And Frame Word
Feb 20, 2006what are design patterns ? what is the difference between design patterns and frameword ?
View Replies View RelatedUsing Factory And Singleton Design Patterns To Create A Simple Form
Nov 16, 2014My assignment was to create a simple form that demonstrates the use of the factory and singleton design patterns. "Use the Factory pattern to ensure that each form input consists of a text label and a textfield. Use the Singleton pattern for the submit button. When the submit button is clicked, a pop-up should show all the information that was typed into all of the form fields."
I used JFrame to create the form without the design patterns and I although I get the desired result, I'm not quite sure how I can integrate the design patterns into the code I wrote. The example I have to go off uses shapes, not text fields so I think that's why I'm not quite clear on how to approach this.
Here's my code so far:
import javax.swing.event.*;
import javax.swing.*;
import java.awt.*;
[Code]....
Factory And Singleton Design Patterns - Building A Simple Form
Nov 20, 2014My assignment was to create a simple form that demonstrates the use of the factory and singleton design patterns. "Use the Factory pattern to ensure that each form input consists of a text label and a textfield. Use the Singleton pattern for the submit button."
Here's what I have:
Form.java file
interface Form {
public void getFormField ();
}
Name.java file (I have a similar files just like this for Address.java, City.java, State.java, Zip.java and Phone.java)
import java.util.Scanner;
class Name implements Form
[Code] ....
It compiles at the moment but I get a null pointer exception in the main method of the FormFactoryDemo file.
Front End Design In Java GUI
Jul 11, 2014I am designing an application I want to know what are the best technology Like Java FX for front end design?
View Replies View RelatedJava Loop Design
Jun 16, 2014Basically I have to enter 5 numbers that I put through a loop and they print the star * depending on the number.An example would be this 5:*****. However, my codes prints out 5:*; 5 times. How to correct my code
Java Code:
import java.util.Scanner;
public class IntegerOutput
{
public static void main( String args[] )
{
Scanner input = new Scanner( System.in );
int num1;
int num2;
int num3;
int num4;
int num5;
[code]....
How To Make A Flat GUI Design With Java Swing
Apr 26, 2014Here is an example of a GUI. Is it possible to make this kind of a thing using Java Swing? Is it possible to have a picture on the entire background of the JFrame, and then other Swing components like buttons, labels etc. sitting on it?Is it possible to have action listeners behind pictures? In other words, they will behave like buttons: the user clicks on them and they do something.
View Replies View RelatedTransferring Coordinates From Design Program To Array In Java?
Mar 6, 2015The idea I'd like to present, concerns the correction of "designer" drawings - those done by the design consultants - against "site/construction" drawings - them being used on site by the workers to build the project itself.
This is normally a laborious process, involving being sat at a desk with two large folders, checking each detail and measurement against the design drawing.What I'd like to present is an idea, where the co-ordinates of the design or "mother" drawing, are transferred into a usable Java program, and they could be then used to ensure correct dimensions have been applied by the the sub-contractors in their "construction" drawings.Like I said, this can normally be a process of days for a site engineer to check - process known as "QA, quality assurance".
Basically, I just need to make a presentation of having a genuine interest in Software Design and Development. It could be applied in a range of areas in terms of construction site application - checking drawings, writing up work orders, dig orders etc - but the principle of having the co-ordinates of the mother or "design" drawing scanned into an array in Java as a means to output those site drawings/orders etc, applies to each potential application.
So - in short - and not looking for crystal clear detail, just general pointers - what programs or methods could transfer a plethora of co-ordinates from a design program like Auto-Cad, to a Java program, where I assume I would then be using a program containing a complex series of loops to ensure the correctness of the derived "construction" drawings; derived from the "mother" or designer drawings, that is.
Java App / Audio Producer - Multiple Consumer Design
Jun 1, 2014I am planning to develop an application that does the following:
1) Receiving an audio streaming from a shoutcast server
2) Decode and push it throught producer to a shared buffer
3) Share audio data to as many consumers are interested to this feed.
What is the best practive for doing this? I tried several things without success.
Nested Patterns Using For Loops
Feb 9, 2015i want to use nested loops to print patterns but i cant seem to make a pattern that will look like V and K this should be the outcome.
* *
* *
* *
* *
*
@ @
@ @
@@
@ @
@ @
EJB / EE :: Difference Between Inversion Of Control And Dependency Injection Patterns
Feb 4, 2015My question is regarding the the Inversion of Control (IoC) and Dependency Injection (DI) patterns, when learning about Spring i saw that people keep talking about Ioc and Dependecy Injection like if its the same thing!
View Replies View RelatedUsing Nested Loops In A Class Called Print Patterns
Mar 7, 2014Write a method to print each of the following patterns using nested loops in a class called PrintPatterns. The signature of the methods are:
public static void printPatternX(int size) //'X' from 'A' to....., size is a positive integer.
#
##
###
####
#####
######
#######
########
Making Patterns (Diamond Shape) Using Nested Loops
Mar 23, 2015I have to make a pattern that is of a diamond shape such as this:
Java Code:
1
1 2 3
1 2 3 4 5
1 2 3
1
mh_sh_highlight_all('java');
I wrote this (for the variable name, this is just a small part of my program and I'm trying to get the pattern right so I didn't mind my variables at the moment):
Java Code:
public class NewFile{
public static void main(String []args){
int k = 0;
for (int i=1 ; i<=5 ; i++) {
{ for (int h=2 ; h >= i ; h--)
[Code] ....
My output is the following:
Java Code:
1
123
12345
1234567
123456789
mh_sh_highlight_all('java');
I realize I should divide the code into a lower and upper triangle using two loops. However, I don't know how to break the first part. I did find the "trend" but I don't see how to implement it.
Stripes / Checkerboard And Double Diagonal (Asterisk Patterns)
Oct 2, 2014I need to make a program that does stripes, checkerboard, and double diagonal. I can not get the stripes to work?
import java.util.Scanner;
public class AsciiArt {
public static void main(String[] args){
int pattern;
Scanner input=new Scanner(System.in);
System.out.println("Choose one of the following patterns by pressing the corresponding number");
System.out.println("1) Stripes");
[Code] ....
How To Design Classes
Mar 29, 2014design a class to conduct a survey of three hospitals. you want to know how many sectors (eg operation, children, gastronomic) each hospitals have, and how many doctors there are in each sector.
what is the process of class design?
Head First Design Pattern
Jan 11, 2014I was reading head first java and the author told to read head first design pattern next.
View Replies View RelatedHandling MVC Design With DatabaseDAO
Mar 31, 2015I have done this a few times but I want to make sure I am doing it correctly. In other words creating a clean understandable program. Instead of posting code I will just talk about this is my plan:
Create a model (getter and setters)
Create a view (via swing)
Create a controller (pass the model and view in the parameter)
Database DatabaseConnection:
Use the singleton pattern
Database:
Create an interface called Database with all the queries I will need (insert, delete etc)
Create a class called DataBaseDAO and implement the interface database and get an instance of the DatabaseConnection.
Tying it all together:
In the controller should I use the "new" operator and create a new database class or extend the database class? I am thinking I should not do it in the controllers constructor but make a field if I use the "new" operator like:
private Database db = new Database();
Create a class called App
Create a new Model
Create a new View
Pass the view and model into the controllers parameter.
Am I on the right track? Is this messy? Is there a better way of doing it?
How To Design - Interface Usage
Jul 17, 2014I have a class as shown below. This class has a method addFilter with 2 parameters (type String and type Command1 )
public class Command1 {
public StringBuffer addFilter(String query, Command1 dataBase) {
//concrete implementation
return query;
}
}
I have another class Command2. Here I need a similar method. The only difference is in the type of parameters passed. (type String and type Command).
public class Command2 {
//TO DO:
public StringBuffer addFilter(String query, Command2 cmd) {
//concrete implementation
return query;
}
}
I have started by using Interface
public interface Helper {
public StringBuffer addFilter(String query, XXXXX parameter2);
}
I would like the classes Command1 and Command2 to implement the interface Helper and override it these two public classes.
However my problem is in dealing with the 2nd parameter. Am I right in my approach? How do I handle this issue?
Design Pattern Selection
Mar 27, 2015I need selecting which design pattern to use in my case.
I am creating a list of objects "items" to be presented in a list for the user to choose from, all objects have a title and a check box. Some objects have additional textbox for user input, some objects have additional image for illustration, and some objects have additional textbox and image as well.
I read and saw online videos but not sure if my selection "Factory Design Pattern" is the best match.
Using Loops To Create A Specific Design?
Sep 10, 2013I am completing the exercises in Java How To Program 8th Edition by Harvey and Paul Deitel.There are two optional exercises GUI and Graphics Case Study Exercises on page 141 Chapter 4.
I have to use loops and control statements to draw lines thereby creating two designs.I am trying to create the design on Fig. 4.20. The lines do not line up correctly.The lines should fan out from all corners. Individually, they look exactly like it should.
Example of one corner.
int width = getWidth();
int height = getHeight();
// upper-left corner
int startX = 0;
int startY = 0;
int endX = 0;
[Code] ....
For the other corners I have different starting and ending positions.To draw upper-left corner I have a starting position of 0,0 and ending position of 0,height.I then move ending position up one vertical step and right one horizontal step. I repeat this fifteen times.
To draw upper-right corner I have a starting position of width,0 and ending position of width,height. I then move ending position up one vertical step and left one horizontal step.
To draw bottom-left corner I have a starting position of 0,height and ending position of 0,0. I then move ending position down one vertical step and right one horizontal step.
To draw bottom-right corner I have a starting position of width, height and ending position of width,0. I then move ending position down one vertical step and left one horizontal step.
For the second design Fig. 4.21 all my lines line up correctly no matter the direction I resize it. Both designs frame size is 250,250. Both designs are divided into fifteen steps.
Servlets :: Simple Web Application Design With JSP
Apr 13, 2014I am trying to design properly a simple 1to50 game (yes, the one that is so popular among mobile apps), but as a web application that allows two player games. I tried to document myself on the technologies I could use and came to the decision that some kind of Java would be suitable. I know that HTML, HTML5, CSS, JavaScript are client side languages with what I can basically design the client application that runs on a web browser. I installed Tomcat web server, configured Java Servlet API, done some research on Servlets and JSP, but I still cannot really imagine how all of this can work. Servlets form the Controller, JSP files the Model? How can I make them communicate, how can Servlets "tell" JSP files what to dynamically generate? Can JSP files communicate with JavaScript? Is JavaScript even necessary?
I thought that this question is not basically about a specific thing regarding JSP or Servlets, more about design and general concept, that is why I put this question under beginning Java.
Design A Class To Represent A Rectangle
Jan 8, 2015I was told to design a class named Rectangle to represent a rectangle.The class contains:
■ Two double data fields named width and height that specify the width and height of the rectangle. The default values are 1 for both width and height.
■ A no-arg constructor that creates a default rectangle.
■ A constructor that creates a rectangle with the specified width and height.
■ A method named getArea() that returns the area of this rectangle.
■ A method named getPerimeter() that returns the perimeter.
Draw the UML diagram for the class and then implement the class. Write a test program that creates two Rectangle objects one with width 4 and height 40 and the other with width 3.5 and height 35.9. Display the width, height, area,and perimeter of each rectangle in this order.Here is my code for the Rectangle Class:
class Rectangle
{
double width;
double height;
public Rectangle() {
width = 1;
height = 1;
[code]....
The error that I am given when I compile the driver is as follows:constructor Rectangle in class Rectangle cannot be applied to given types; required: no arguments; found:int,int; reason: actual and formal argument lists differ in length.
Servlets :: How To Design A Shopping Website
Nov 23, 2014I am working on a Project of Ecommerce Shopping WebSite in Java.
First I Decided to use Servets,JSP,Spring,hibernate etc.. from Scratch to design its Layouts and Functionality.
But After Reading this Thread [URL]...
I Found that there are already some Ecommerece Solution that are availabale in Java Like Magento.
Is it worth To use these Ecommerce Solution for Development Purpose of Premium Purpose.
I read that some of them are Open Source.
If a ShoppingCart Solution is OpenSource then Can We Use that to develop and Distribute for Premium Purpose?