Java EE SDK :: How To Access Remote Persistent Objects From Web Front Client
Apr 1, 2012
I have a doubt about how to design a web application which has their persistent objects in a service layer in a remote server, i mean a business application. So, once we have a web application as a client of this remote business application, how those persistent objects should be mapped in web front?
Should I either pack all jpa annotated classes into the web front application or there is another neat way to do this?
I was intending in copy all persistent classes present in the remote business application into the web app package, i know it's not the best way to get what i need.
What is a more appropriate design for a web application which must get some objects from a remote business application and persist some other objects there?
For the assignment, we are supposed to make a checkerboard with alternating colors, then put images on top of certain spaces to act like "pieces." I did the checkerboard, but whenever I go to try and put an image the checkerboard, it doesn't appear! I put the image in the same directory as my other code as well. I did some experimenting and discovered that the image is appearing, but behind the checkerboard.
Here is the code:
import java.awt.*; import javax.swing.*; public class CheckerBoard extends JApplet{ public void paint(Graphics g){ super.paint(g); Image img1= getImage(getCodeBase(),"arrow1_nw.png"); g.drawImage(img1,500,500,this);
I am trying to prepare for the next installment Java course. I found a syllabus online from last year. All I'm trying to say is that I am not in this course but will be shortly. I tried the first project but I am having subclass issues. I want to access the getStock method in the Executive subclass from the client. I keep getting a cannot find symbol: method getStock from class Employee. I don't know why won't access Executive.
Main:
import java.util.*; public class EmployeeClient extends Employee { public static void main(String[] args) { Scanner input = new Scanner(System.in); //variables String name = " "; int totalSalary = 0; int stock = 0;
I'm trying to pass an object to a server and then back again. The object gets to the server fine, but either the server doesn't return it correctly or the client isn't accepting it. There's not error's. The client just prints the object as null. Not really sure why, I looked at other examples and they seem to be the same.
Client:
public class main { public static void main(String[] args) throws IOException { String serverAddress = JOptionPane.showInputDialog( "Enter IP Address of a machine that is" + "running the service on port 9090:"); Voter you = prompt();
In my application i have two classes which implement EntityBean class.
Container Managed Persistence is achieved through this implementation in the extending classes.
When i have seen snapshot of the Heap Dump this morning i.e after a period of 12 hours of non-usage or applicaiton idle state the object instance still persist and memory is allocated to them instead of getting Garbage collected.
Is this behavior expected of these objects if so how to overcome over-usage of memory by these objects ? .... in order to avoid performance issues or possible memory leaks.
I am messing around with a Swing application and am a bit stuck as to how to join the front and back ends.This is the code for the DataManager class which is responsible for loading and saving objects and interfacing with rest of the system. The data I need displayed comes from a .txt file in the applications directory. I need to show certain aspects of the data in the JComboBoxes in the GUI class.
Java Code:
package programdataapplication; import java.io.*; import java.util.*; public class DataManager {
I've been unable to figure out how to access an objects data from another class. I ended up missing a lesson in java and haven't been able to catch up on this topic on my own through my textbook.
Error: has private access
Code:
public class TestCoffeeDrinker { public static void main(String[] args) { Coffee latte = new Coffee("Starbucks Tall Latte", 2.85); Coffee mocha = new Coffee("Starbucks Grande Mocha", 3.95); Coffee mcdonalds = new Coffee("McDonalds McCafe", 0.99); System.out.println(mcdonalds.toString());
I want to keep count of how many students are in my array. the array i made up of objects from other classes. like the class Student how do i do this. i have tried contains but better way it to to a loop to go through the array and determine if each object is a particular type but i don't know how to do this. here is the code
import java.util.*; import java.util.ArrayList; public class Driver { public static void main(String[] args){ /* Comments required PersonFileReader pfr = new PersonFileReader("person.dat"); ArrayList<Person> testData = pfr.readData(); Database db = new Database(testData);
I have a servlet. Users from other machines access that servlet and I want to capture the remote user's UserName and do validation over that.It's just a simple servlet and no login/password is present. I tried request.getRemoteUser(), but its of no luck.
From java running on Windows, I need to access a file on a remote Ubuntu machine. I use the following:
URL U = new URL ( "http://" + SERVER_IP + ":" + SERVER_PORT + "/" + ClsName + ".class" );
where:
SERVER_IP is the Ubuntu IP address obtained from any site that shows the IP address of the machine you are using.SERVER_PORT is the Ubuntu port where the server is listening.
Now:
Do I need to modify this code any further?Do I need to configure the Windows and/or Ubuntu machine(s) for this to work?
I have tried each and every thing in all the other answers. Like setting chunked to false, changing parameters, changing http1.1 -1.0. I am just writing a sample client to compare it with my real time client. Following is the code of client:
package com.webservicemart.ws; import java.rmi.RemoteException; import org.apache.axis2.AxisFault; import com.webservicemart.ws.USZipStub.ValidateZip; public class UsZipClient { public static void main(String[] args) {
[Code] ....
And Following is the error :
[INFO] Unable to sendViaPost to url[http://www.webservicemart.com/uszip.asmx] org.apache.axis2.AxisFault: Transport error: 404 Error: Not Found at org.apache.axis2.transport.http.HTTPSender.handleResponse(HTTPSender.java:310) at org.apache.axis2.transport.http.HTTPSender.sendViaPost(HTTPSender.java:194) at org.apache.axis2.transport.http.HTTPSender.send(HTTPSender.java:75)
[Code] ....
I have tried with other geoIP service and weather forecast too. I get the same error.
A data entry form is on the front end. This allows one to enter say emails, addresses, etc. It utilizes a jsp, jstl, servlets, and beans. The backend sql has say a size of 50 for email. If more than 50 char are entered on the form, w/o any intervention, a truncation error is thrown. A static class was set up to hold the input element names and max sizes. It seems to work well keeping all in check, names and sizes on form, names in servlets, size of sql.
servlet .getInputElement("date").getInputName() //static map...shared with above objects
Is there any other system of keeping everything in sync. I am building it all, but I was wondering how this is parsed out if there are separate sql, middle-tier, and front-end developer? It seems better just to have good documentation that would be shared between the different implementers.
I'm new to web services. Right now i'm trying to consume JAX-WS web service on IBM WebSphere Application Server 7. Sending SOAP message with security header[username, password] parameters. Getting NullPointerException..
Exception :
javax.xml.ws.WebServiceException: java.lang.NullPointerException at org.apache.axis2.jaxws.ExceptionFactory.createWebServiceException(ExceptionFactory.java:175) at org.apache.axis2.jaxws.ExceptionFactory.makeWebServiceException(ExceptionFactory.java:70) at org.apache.axis2.jaxws.ExceptionFactory.makeWebServiceException(ExceptionFactory.java:128) at org.apache.axis2.jaxws.marshaller.impl.alt.DocLitBareMinimalMethod Marshaller.demarshalFaultResponse(DocLitBareMinimalMethodMarshaller.java:443) at org.apache.axis2.jaxws.client.proxy.JAXWSProxyHandler.getFaultResponse(JAXWSProxyHandler.java:559) at org.apache.axis2.jaxws.client.proxy.JAXWSProxyHandler.createResponse(JAXWSProxyHandler.java:497) at org.apache.axis2.jaxws.client.proxy.JAXWSProxyHandler.invokeSEIMethod(JAXWSProxyHandler.java:404)
I'm a student designing and developing an Air Traffic Control (ATC) system for incoming aircraft, mainly implementing the part which handles the queuing system for approaching aircraft.
I'm using Dr.Java and doing a numbershifter lab. I have to create a random array of number from 1-10. Then move all of the 7s to the front of the array. The order of the other numbers is not important as long as all numbers follow the group of Lucky 7s. Files needed Numbershifter.java and numbershifterrunner.java. All data is random.I have done the following:
public class NumberShifter { public static int[]makeLucky7Array( int size) { int [] newRay = new int[size]; for( int i=0;i<newRay.length; i++) { newRay[i] = (int)Math.round(Math.random()*10+1);
basically I'm a good way through developing a Poker game which I've been developing just for fun(!?) and also to improve my skills, which it has done substantially. The logic involved with some of the hand comparisons and the evaluations of the winner is pretty complex.
Nonetheless, once I've finished the threaded timer to control the regulation of rising blind levels, and the betting mechanics for the Computer players I'll be looking to start creating the front end and this is where I'm a little confused.
Obviously for what I want, neither swing or AWT would be sufficient, so I guess the gap in my knowledge is how to integrate my back end code with a web front end. Is this possible? - What options exist for integration? just pure CSS / JS, or would Angular.js be viable? I'm looking to utilise some ready made images as graphics with maybe some minor animation effects.
Code for implementing a simple computerised version of Battleships has been supplied. Examine the code ensuring that you understand it. The game is played against the computer.
A number of ships (default is 6) are place randomly on a 4 x 4 grid. A ship occupies one square only. The player then guesses the position of a ship. If he/she guesses correctly the ship is HIT and sinks. If the guess is incorrect the player loses a life. The default number of lives is 7. If the location has been guessed already, no lives are lost.
When the game starts, a 4 x 4 grid should be displayed.
The user should be allowed to enter/select a cell location. If the selected cell contains a ship, the ship will be destroyed. If not the player loses a life. The cell should display an appropriate picture, icon or message informing the user of its current state.
The number of lives and number of ships remaining should be displayed.
When the game ends an appropriate message should be shown informing the player whether he/she has won or lost. The positions of the ships should also be shown.
The purpose of this assignment is that students demonstrate an understanding of the Java Swing library and that he/she can navigate and use the API effectively.
Your finished GUI should be both user-friendly and aesthetically pleasing.
Ideally, the user should have the option to play another game, to quit or give up mid-game. You may also wish to include other options such as different levels of difficulty, etc.
I'm working on an assignment right now which involves passing a variable series of numbers to the Server to be sorted into the correct order and returned to the client.
So far I have it connecting to the server and asking for my numbers, and I am entering each number and pressing return, and it is accepting each number individually.
One (smaller I think) problem i'm having is with the client code, specifically the while loop.. I've tried to code it so that when I enter a full stop ('.') the program will stop asking me for more numbers and move on to sending them to the server.. but instead it just crashes giving an error.. heres an example
"Enter a number: 1 Enter a number: 3 Enter a number: 2 Enter a number: 1. java.lang.NumberFormatException: For input string: "1." at java.lang.NumberFormatException.forInputString(Num berFormatException.java:65)
[Code] ....
Here's the client code in full
package numberSortprogram; import java.io.*; import java.net.ServerSocket; public class NumSortClient { public static void main(String[] args) { InputStreamReader is = new InputStreamReader(System.in); [Code] ....
The big problem that I have is figuring out how to send the sorted array back to the client..
So, what im trying to get to happen is-
-Client is asked to enter numbers -Client enters series of numbers into an array -Array is converted to a string and sent to the server -String is then split into an array of strings and sorted using compareTo (don't know if this is the best way?) -Sorted array is sent back to client and displayed.
fyi this is making use of streamsockets..
All of the rest of my code is below:
package numberSortprogram; import java.io.IOException; import java.net.*; import java.util.regex.PatternSyntaxException; public class NumSortServer { public static void main(String[] args) { int serverPort = 4444; // default port if (args.length == 1 )
For a shool assignment i have to create a java irc client. which responds to commands. the !SENDMSG command has two parameters !SENDMSG <username> <the message>.
i can get the username and the message seperated, but i would like to create a check in case someone gives a bad command like: !SENDMSG" " <-- note te extra spaces, or if someone gives only 1 parameter.
I am currently writing two java classes (client and server). The client takes an input number form keyboard and sends it to the server. The server then multiplies this number by two and sends it back to the client. The numbers should also be printed to screen along the way, for example if I input the number 3 I should get
"From Client: 3" "From Server: 6"
They should continuously do this unless a negative number is received by the client, say for example the number -3 is sent to the server and it returns -6.
The code I have for the two classes so far is:
import java.io.*; import java.net.*; import java.nio.ByteBuffer; import java.util.Scanner; class Client { public static void main(String args[]) throws Exception { DatagramSocket clientSocket = new DatagramSocket();
[Code] .....
Currently, when I run the program all I get is an output of the number first entered. I am aware it requires a loop but I don't know where and what the condition should be.
Also if I wanted to adapt this so that it would take the integer from client and subtract two at the server and return to client who sends back to server to keep subtracting two unless it reaches a negative number at which point the client will terminate the program - how might I do this.
I do realise there needs to be a while loop in the above code, but I wanted to test it sent the number from client to server and its not doing it. All I get is a print screen of 'enter number' and then the number I enter.
I have created a sample java web service client using Apache Axis. It works well with basicHTTPbinding (without security and Basic authentication).I am not able to make a secured communication. How to make it work in a secured way using NTLM or any other security.
ejb. Using Eclipse and Jboss server. I've deployed an EJB and now want to invoke it using a standalone java program. I know that Eclipse and JBoss do some job to bind JNDI names. I just want to know that how to lookup EJB by which JNDI binding out of 6 options available (shown in deployment console) there.
Here I'm dropping all my java code and server/console logs...
