Recreate Image On Client / Parsed In Json Object From Server
Apr 14, 2015
I have written a program in JAVA which fetches an image from MYSql Database. I get a BLOB object then I am trying to convert that BLOB object to string; again I am using that object to write the image to a file. the image file is getting created in E: but it does display any image
I write a Client/Server program,trying to send and receive a object between client and server. I use the ObjectStream but there exists an EOFException on the client side when invoking readObject() .... I've tried many times but couldn't figure it out ...
server-side code
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { try{ ObjectOutputStream out = new ObjectOutputStream(resp.getOutputStream()); ObjectInputStream in = new ObjectInputStream(req.getInputStream()); PersonalData pe = (PersonalData)in.readObject(); System.out.println(pe.getYearlySalary());
that i started to learn programming and i started with java. so there is a book that i'm on it right now called "Pearson Absolute Java 5th Edition" by Walter Savitch anyway i'm on a project in fifth season which i have to create a class named HotDogStand that operates several hotdog stands distributed throughout town. the whole program is clear. although its so easy to accomplish , my question is more about debugging. so here is the code:
public class HotDogStand { private int id; //id number of hotdog stand private int hotDogsPerDay; //hotdogs sold by one stand private static int totalHotDogs; //the static value for total hotdogs sold by all the stands public HotDogStand (int newID, int hotDogsPerDay) { this.id = newID; this.hotDogsPerDay = hotDogsPerDay; totalHotDogs += hotDogsPerDay; //to add the value every time the user uses the constructor (every time the user creates an object)
[code]....
everything works fine. but my question is what if someone use a constructor again? you see if in the main method someone do this after creating the object "stand3":
HotDogStand stand3 = new HotDogStand(3, 43); stand3 = new HotDogStand(3,40);
i know that it's logical to use setter method but this program doesn't have one. if someone do the thing i wrote above, the calculation of static variable, totalHotDogs will be all wrong. because of totalHotDogs += hotDogsPerDay; it will add another value for the same object. how can i tell the machine to ignore the second (or more) invocation of the constructor for the same object?
I'm new to json and the web. My purpose is to use json data from a server and parse it and show meaningful data to the user. I am aware of json parsing, so no sweat there. However, I would like to know how json data is sent to the front end after which it can be parsed.
Usually in my json parsing examples, I have a variable like var data = ]OR I do a getJSON on a data.json file which I have stored in the project folder. However, I want this data to come real time from a servlet. How to go about this?
So, basically my question is, how do I send real time json data from a servlet backend, say some records which I have extracted from the database using jdbc?
i have a service to save some form fields from the client and i need to add uploading image to that service using json. the service consumes json and produces json.
I'm trying to pull the authors from this Json object but I'm having issues trying to pull the author only, I'm only able to get a huge string which is a valid JSON object i tested it in [URL]
I am attempting to test a TCP Client and Server for an assignment I am doing in class. The goal here is to "test your client and Server applications by transferring (i) a file having 10,000+ lines (see supplied big-file1.txt having 12000+ lines), (ii) a file having 20,000+ lines (you may create one of your own from big-file1.txt, or obtain a large size file from the Google website at [URL] ...). Then, compute and display the total transfer time of the files at both of the sides separately (your choice in millisecond/second)."
I have created the TCPClient and TCPServer java classes, ran the server first and then the client, and using mathematical formulas to calculate the transfer time. Trouble is, I'm having trouble testing the client and server in the file area and not the area where I had to input a line, let the server print it, and then have the client eliminate the articles from the line. I need testing the file. Here is my code so far:
TCPClient:
package tcpclient; import java.io.*; import java.net.*; public class TCPClient { public static void main(String[] args) throws IOException{ // TODO Auto-generated method stub String sentence;
[code] ....
How to fix the code so that the time in seconds does not output as 60 for both files and that the files go through the exchange?
I have a program using Pipe line to exchange the infomation in the Client-Server model. Can I separate out main function and then put into Server main and Client main?
//PipeEchoServer public class PipedEchoServer extends Thread { PipedInputStream readPipe; PipedOutputStream writePipe; PipedEchoServer(PipedInputStream readPipe, PipedOutputStream writePipe){ this.readPipe = readPipe;
I have to develop a code in parallel which is implemented in sequential yet. How to add the server client relation in the program so that work can be divided into multiple clients.
I've just recently started playing around with network programming in Java, and I've come up with a simplistic server than can handle multiple clients and return the IP and port each one is connected to (or I'm under the impression that is so). What I've been requested to do as an exercise by one of the programming teachers at my high school (I'm not in a class, this is my own time) is send a message from one client to the other through the ServerSocket so that it may "watch" everything going on. I'm not sure how to go about this at all.
EDIT : now it never seems to go the the else or else if statements...
That is now the main problem. It never, ever, goes past the first if statement, no matter what it is.
EDIT : Okay, I haven't changed a line of code but suddenly not a single if statement is working. They just stopped. The client simply hangs and I can't type anything.
Server
public class Server implements Runnable { Socket clientSocket; Server(Socket clientSocket) { this.clientSocket = clientSocket; } public static void main(String args[]) throws Exception { ServerSocket ssock = new ServerSocket(3480); System.out.println("Listening on port 3480");
I have a problem on how to make my client to send the object to a server.
So I have one interface called "RMIInterface" and client "RMIClient" and server "RMIServer":
RMIInterface interface RMIInterface { public String getMessage(String text) throws RemoteException; } RMIClient public class RMIClient {
[code]....
With this program I can connect to a Server with a Client, and print in Client console a message.But, how can I send message from a client to a server, and print that message in server console output?
make the simpliest example with sending a message to a server, edit inteface header code to public interface RMIInterface extends Remote, I forgot to add.
I want to ask that, when a server listen to A port and it accepts a request from a client then the server accepts the request using accept method,but how does the server get the info about the client like wat is the port no and ip address of the client,I read a answer regarding this that Server never gets the port no of client only the ip address and it connects to client using a connection stream but as far I know from networking, a device must have the ip address and port no of the device it wants to connect to.
So we have a Client and Server. Client opens a socket to Server, server initiates new Thread to handle the communication with client. Is there a way to be singnalled when there is input on socket, so I don't have to use infinite while loop solution?
I have gf 4.0.1 and swing client. I want to get EJB over SSL. I've set all certificates. However, I can get it work only when client and server are at the same host. What I see in tcpdump when they are at the same host:
I've been trying to create a server/client chat program, but I keep running into areas where I'm not really sure how to work it. I've run into a wall where my client just sits and spins instead of working. URL.... I can work out the dynamic parts later, I just want to understand the meat and potatoes of reading from sockets and writing to sockets (and how to do both at the same time).
I'm trying to build a SSL mutual authenticating private server. I'm not sure what keystores, truststores, or certificates I need to accomplish this. I made keystores for both programs using:
It's an RMI program that has to be able to return the mean, mode and median of a set of numbers.It's composed of 4 classes; a client, an implementation class (with the math), an Interface, and a server class.
So i wrote this text to try and create a simple chat program that does the following: Prepend names to messages, announce entrance and exit of chat, display user list, and share a whiteboard.So far the Server seems to be working but the Chat Client is throwing errors at me left and right..
CURRENT ERROR: Microsoft Windows [Version 6.1.7601] Copyright (c) 2009 Microsoft Corporation. All rights reserved.
C:Windowssystem32>cd.. C:Windows>cd.. C:>Usersjaydesktopchat 'Usersjaydesktopchat' is not recognized as an internal or external command, operable program or batch file.
I am creating a server that stores application updates. When the client connects the server send the update. The server is sending the file but the file is not complete, i.e, if the file is 317kb,its send 117kb. Below is the code I am using :
import java.io.BufferedInputStream; import java.io.File; import java.io.FileInputStream; import java.io.IOException; import java.io.OutputStream; import java.net.ServerSocket; import java.net.Socket; public class TestFileServer {
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 )
I want to send a message to a specific client in a server. This is my code and what I tried(I have only given you 3 classes in which I believe I have the problem).
TextClient:
import java.io.*; import java.net.*; import java.util.ArrayList; import java.util.Scanner; import java.util.concurrent.TimeUnit; public class TextClient { public TextClient() {
I've been provided a code skeleton for what must be done, but despite my best efforts to make things work, I'm coming up dry (obviously, due to a lack of knowledge.) One thing that might work is if I knew how to debug this type of application, line-by-line, to see exactly what is going on. Obviously, it's easy enough to debug the client part, but moving over to the server part, I haven't been able to figure that out (I'm using Eclipse.)
