Using Java 7 update 5 (I know it's old...), we are trying to send concurrent requests to a RMI Server. When we start to tamp up the load (not too much - up to 50 concurrent requests) we start to see many IO Problems like Broken Pipe and Connection Reset By Peer. Could we be hitting some unknown limitation on concurrent access? Is there such limitation?
View RepliesI want to write java code which can block unbuffered I/O requests send to CD driver ...
View Replies View RelatedI have written the following code to handle multiple Client Request. Lets Assume that it takes server 300 nano seconds(ns) to process one connection request. It recieves two connection requests at time t1 and t1+200ns. Since server is busy handling request 1 at time t1+200ns. what will happen to request 2.if yes what is the max size of that buffer?Maximum number of request that a server process per unit time depends on the java code.Is there also a limit to how many request a server can recieve per unit time?
public class EchoServer
{
public static void main(String args[])
{
ServerSocket serverSocket = null;
BufferedReader readSocket = null;
PrintStream writeSocket = null;
serverSocket = new ServerSocket(9998);
[code]...
Is there any kind of way to generate HTTP request within a servlet, dispatch it to the server and get back the answer delivered to the servlet? Or are the servlets meant only to respond to passed requests, not generate them?
(I asked a similar question here: [Code] ..... but no luck)
What's wrong ? I'm trying to send parameters in a link so I can get this parameter (an id) and get all the forum-threads that are relatives to this parameter. Because I can't set attributes in a link. Or can I ?
<c:out value='<a href="<c:url value="threads.jsp">
<c:param name="idSub" value="${subforum.idsubforum }"/>
<c:param name="subName" value="${subforum.name }"/>
</c:url>">${subforum.name}</a>' escapeXml=""/>
does not work but I read it's not used in html. I'm really lost on this one.
i am beginner in java. i was try to send email with MailAPI, follow is my code and error
import java.util.Properties;
import javax.mail.Session;
import javax.mail.internet.MimeMessage;
import javax.mail.internet.InternetAddress;
import javax.mail.MessagingException;
import javax.mail.Transport;
import java.util.Date;
import java.text.SimpleDateFormat;
[Code]...
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 am trying to connect to a local service over UDP - the simulator works fine, but my code does not... The sender is a separate thread and I have tried blocking, non-blocking, connecting, not connection, reading and re-reading the Oracle docs,
Java Code:
package my.comm;
import my.myMethods;
import java.io.IOException;
import java.net.InetSocketAddress;
import java.nio.ByteBuffer;
import java.nio.channels.DatagramChannel;
import java.util.LinkedList;
import java.util.Queue;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
[code]....
What is the best way to send an arrayList from the server to the client? ObjectInputStream and ObjectOutputStream?
View Replies View RelatedI'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 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() {
[Code] .....
I made an application and i can send the message/notification to all loggedin users immediately. But the problem is that i am unable to send notifications to a specific user; as an example facebook chat.I am using Servlets 3.0, Spring MVC 3.0, GSon and AJAX Jquery.
Here is my code:
web.xml
<web-app id="WebApp_ID" version="2.4"
xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee
http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
[code]....
<%@ page import="javax.print.*"%>
<%@ page import="javax.print.attribute.*"%>
<%@ page import="java.io.*"%>
<%out.println("Printing...");
String filename = "c:/20140505_3_40.txt";//this is the text file i want to send to printer
// am using tomcat 8
PrintRequestAttributeSet pras =
new HashPrintRequestAttributeSet();
[Code]...
I am trying to create a serversocket that send a binary in parts ie send 1024 bytes then wait for acknowledgement from the client before sending the next 1024. I am able to do it in udp but the client is tcp. This is my code so far
import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.ServerSocket;
import java.net.Socket;
public class TestFtp {
[Code]....
I have not been able to send then receive acknowledgement before sending the next 1024 bytes.
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());
[Code] .....
I'm creating a web applicaion. for that i want to create a registration page. and this registration details have to be stored in the database.
I'm getting the below error while trying to send the data ...
The requested resource (/cmd/InsertRegtodb) is not available.
Here cmd is project name and InsertRegtodb is servlet name.
Actually the servlet is present is the mentioned address. but it is not connecting to it
There is one more servlet in the same folder and which is accessible from another jsp. But this servlet is not accessible even though i have used same code as it is used for the servlet which worked for me previously...
I'm trying to do a program that send a single file from a client to a default directory of a Server. The program use the datagramSocket and datagramPacket for the transfer via UDP. The client sent the packet of the file correctly and the server start the receiving but every time the Server class crashes after it's receiving 4/5 packet (exactly 8192 byte)
Then i put the code of the 2 class and the 2 output.
OUTPUT CLIENT:
PROGRAM TRANSFER PACKAGES
name of file is : Doc1.pdf
his dimension: 11408 byte
*** start sending
- 1024 byte
- 2048 byte
- 3072 byte
- 4096 byte
- 5120 byte
- 6144 byte
- 7168 byte
- 8192 byte
- 9216 byte
- 10240 byte
- 11264 byte
- 11408 byte
*** FILE SUCCESFULL SENDED***
BUILD SUCCESSFUL (total time: 3 seconds)
OUTPUT SERVER
PROGRAM TRANSFER PACKAGES
START NEW CONNECTION
Directory: C:prova
Server waiting in port: 9876
Waiting Client...
Name of file is : Doc1.pdf
Dimension : 11408
[Code] ....
In this point the program go in loop and didn't anything. I don't understand how can i resolve it...
SERVER
package udp_pacchetti;
import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
[Code] ...
I am currently trying to access an EJB Session deployed in a Weblogic server from JBOSS.
The client code looks like this :
Hashtable environment = new Hashtable();
environment.put(Context.INITIAL_CONTEXT_FACTORY, "weblogic.jndi.WLInitialContextFactory");
environment.put(Context.URL_PKG_PREFIXES, "weblogic.jndi.factories");
environment.put(Context.PROVIDER_URL, "t3://<ip>:<port>");
InitialContext context = new InitialContext(environment);
ServiceHome home = (ServiceHome)context.lookup("ejb/Service");
When I run this code from a standalone java program it executes ok, but when I try to run it from an application deployed in JBOSS, the line (5) which creates the InitialContext object throws this Exception :
java.lang.ThreadDeath
org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1221)
org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1181)
weblogic.rmi.internal.StubGenerator.getStubClass(StubGenerator.java:696)
weblogic.rmi.internal.StubGenerator.generateStub(StubGenerator.java:742)
[Code]....
In order to be able to use weblogic naming factory I put the archive weblogic-8.1.6.0.jar in jboss's /server/default/lib directory. But I think it has to do with JNDI conflicts between JBOSS and weblogic.
I am developing one android chatting application. for that on Server side i am using WebSocket as war file.
It is working well on localhost the same tomcat. but when i try to connect on the hosting server, it showing http error..,
I am trying to check SFTP connection to remote server using enchanter jar. Mine is not a multi-threaded application. PFB sample code...
.....
SSH ssh = new DefaultSS();
ssh.setTimeOut(10000);
ssh.connect("myserver","myusername","mypassword");
ssh.sendLine("cd /u");
ssh.sendLine("sftp -B batch.file utodldse@claoesdsdd.com");
ssh.getLine();
.....
note - the batch.file contains only 1 statement. Please find below.
---
bye
---
But the above program is getting is stuck at times when the server is not responding. It goes into infinite hung state.
Is there some alternative ways to set timeout ?
I have a code that uploads files in server after browsing folders and files then get the paths of files but I have a problem in getting the paths
List items = upload.parseRequest(request);
Iterator iterator = items.iterator();
while (iterator.hasNext()) {
FileItem item = (FileItem) iterator.next();
if (!item.isFormField())
{ fileName = item.getName();
root = getServletContext().getRealPath("/");
path = new File(root + "/uploads");
[Code]...
list1 must has paths that I want but I do not get the paths of upload files
I have been trying to implement custom request method in HTTP header while posting my data to the server URL. My application specific URL accepts -X parameter and -d for the data and it is mandatory for that url. Basically I am trying to dump JSON data into my influx DB using CURL command which is working fine from the shell. But the issue is, if I am implementing the same in java with proper approach, it is not supported or working. My CURL command is :
curl -X POST -d '<my_json_data>' '<my_url>'
How can I implement the same in java using HttpUrlConnection or other available approach?
So I've been working on this program to make tournament matches for beach volley.
First little info: (I'm Belgian so some words are Dutch)
-Class Speler: has arraylist with information with which player already has been played (codesLijst)
-Class Inschrijvingen: makes players sign up with their level and name
-Class Wedstrijd: makes matches, checks with Inschrijvingen if the players already have played together. If so, gives message that they need to change partner. If not, makes them a team.
Now if I run the program with fresh players, none of them have had a partner, it works fine. If I make just one new team and the other already exists, it also works fine. It's when I make the two teams with existing records (to see whether they already played together), that the error comes.I know there's a lot of code duplicate, will clear out eventually, this is just a raw version.
CLASS SPELER
import java.util.ArrayList;
public class Speler {
private Wedstrijden wedstrijd;
private Inschrijvingen inschrijving;
private String naam, ploeg;
private int setPunten, winPunten;
private long time;
private String code;
private ArrayList<String> lijstCodes = new ArrayList<String>();
[code]....
My code is like this,
for(Iterator iterator = list.iterator(); iterator.hasNext();) {
String string = iterator.next().toString();
list.add(string + "Hello");
iterator.remove();
}
Its a simple program. I've list with some names as values like,
Ram, Sham, Bham, Bhim, Suraj.
Now, I want to add "Hello" to each name by running above code. While iterating, first time I get Ram, I want to add "Hello" to Ram and add to list as "Ram Hello" also I want to remove original Value i.e "Ram". When I run above code it is giving Concurrent Modification Exception. How to do this?
What I am attempting to do is execute a long-running process and iterate over it multiple times. I'd like my page to update with the progress in between each run. What I have tried so far is using a HttpSessionAttributeListener and executing my long-running process from there and using my ViewScoped bean along with richfaces a4j:poll to update my page. Unfortunately no matter what method I try with a listener, the completion of the Partial JSF lifecycle always blocks until my listener method is through processing. So we go from start to finish with no updates in between.
I have which is to just have my view re-submit itself and try updates that way. But before I go that route I wanted to see if there was a way to do what I was originally attempting and I'm not just missing something.
I'm writing an IRC server in Java, however when a client tries to connect I get a ConcurrentModificationException trying to add them to an ArrayList. My code is Here: [URL]
I don't understand why I am getting a ConcurrentModificationException or what one is.