I am familiar with Servlet/jsp's and developed a web application using them. Now I am looking in Websocket of Java 7. Documentation is not clear how to integrate the two.
1. Let us say in my listener, I have already determined database connections, log file for log4j etc.. Can I use it in Websocket Java classes based on annotation API of web socket. What is not clear to me how I will access Context parameters for webapp saved in Listener.
2. I like jsp so I can dynamically modify the html to be shown. If I am using api, how will I do that, I know I can return data from websocket, but all the java logic which jsp provides, how can that be implemented using web socket api.
MDS don't support all six transaction attributes. MDBs support only REQUIRE or NOT_SUPPORT.... There is no existing transaction to suspend or join when a message is delivered, The two options you have available are REQUIRE if you want a transaction.....
there is no existing transaction when a message is delivered from a queue to an MDB. Why we still need a transaction as it says " REQUIRE if you want a transaction"? When a message is delivered from the queue to the MDB, is this a transaction?
->When the user request for a file that is not exists i want to redirect to a valid url where i can inform him that the file does not exists. ->I am trying to use the properties messages for the language that the user has. I want to use it cause i want to reuse some of the message and it is easier to translate the page to other languages. How when the browser has a default page English to let user change the language to Italian for example but for all page.
I studied that java does not support multiple inheritance using classes. It is fine practically, but I have still a question in mind:Lets see the below code.
class Test{ ------ ------ }
class MyTest extends Test{ --------- --------- }
Here, as we know that that Object is Super class for every class in java. and I have already extends a Test class in MyTest.My question is: How is it possible to extend features of two class at the same time?
I need to port asynchronous bean (provided by websphere) support in App servers like weblogic and jboss. Is this feature already part of J2EE specification? Or should I use some other external package to get this feature?If so what are those async bean like features for weblogic and jboss?
So I'm working on some networking code and I have the Server running as its own thread, then I have a PacketListener which is contained in the Server, that is running on its own thread too. As of right now, the PacketListener waits for packets via DatagramSocket.receive() and then adds them to a queue. The Server runs in a loop and it checks that queue for packets and then polls the most recent and process it before sleeping for 1 millisecond. Here is my question though, I'm considering changing the program to a more observer pattern structure in that when the PacketListener would receive a packet, rather than add it to the queue, it'd notify the server which would process it. However, wouldn't this cause additional time required within the PacketListener thread dedicated to processing the packets rather than listening for them?
I have a requirement to get the details of the files present in a directory on a server. I need to get the file names and timestamp. I have the below code to get the file names:
Connection conn = new OracleDriver().defaultConnection(); ArrayDescriptor arraydesc = ArrayDescriptor.createDescriptor ("DIRLIST_T", conn); File myDir = new File (dir); String[] filesList = myDir.list(); ARRAY dirArray = new ARRAY(arraydesc, conn, filesList); return dirArray;
But am not able to get the timestamp. How can I get the timestamp as well.
I would like to limit my bandwidth usage when accessing/downloading files (similar to the --limit-rate 50K option for curl and wget) as the website has limited bandwidth. I am not exactly sure how to implement this, but I'm guessing it be accomplished via the BufferedReader? I have attached the current code below.
I have noticed an error, that makes sometimes troubles, when downloading jars from https addresses, when there are many jars to download..
Best example is by opening Javas on Java version checker. [URL] ....
I get also following log...
network: Connecting https://www.java.com/jsp_utils/jreverification.jar with proxy=DIRECT network: Connecting http://www.java.com:443/ with proxy=DIRECT network: Connecting https://www.java.com/jsp_utils/jreverification.jar with cookie "JSESSIONID=22ABBA2BE9B5789629C276AC35BDF969; s_cc=true;
Even if the address is https, java try to access via http protocol on port 443, and that leads sometimes to problems..
I have noticed this, when I have used URLConnection(HttpURLConnection) for my self, as soon Java sends http link on https address, the jar gets sometimes not loaded, and i get error about missing class that get called..
On http addres it is not so bad, since same protocol is used, but evidently, that is evil for https..
As you see, that happens already when loading Jar by Applet Starter and at all, it happens each time on any URLConnection
############################### Java Plug-in 10.13.2.20 Using JRE version 1.7.0_13-b20 Java HotSpot(TM) Client VM User home directory = X:Usersadmin ---------------------------------------------------- c: clear console window f: finalize objects on finalization queue g: garbage collect
I wrote a proxy in java. The version with ServerSocket-Socket/Stream-IO works wonderfully. When I rewrote it to ServerSocketChannel-SocketChannel/ByteBuffer it works also very well. However, when I access YouTube things happen weirdly: The video is frozen after 3 or 5 minutes (but this did not with the version of ServerSocket/Socket). I strongly assume that there probably was a nasty bug.... The (shortened) codes are:
Server: public class BeanServer extends Thread { public BeanServer( ) { } public void run( ) { try { bServer = ServerSocketChannel.open();
My application with Oracle Database only works with Ethernet, I tried to connect via wireless without any response. When I run the command netstat the port state is WAIT TIME and then be closing. The clients machines run Windows 7 and 8 and the server run Suse Linux Enterprise Server 10 SP2, if the client machine run XP all works fine. I disabled the firewalls in the both sides.
We have a servlet application running under jboss 7.1.1/java 1.7 that sends http requests to another server. Everything works fine for most of the time, but occasionally (from one to a couple of times a day) we get a “Socket closed” exception. I’ve been trying to find out what might be causing this but so far I’ve been unsuccessful. By the way, this has been happening while the application was running under older versions of Jboss/Java so the version might not be that relevant.
Here’s an excerpt from the method where this happens: . . . . . try { HttpURLConnection conn = (HttpURLConnection) urlEndpoint.openConnection(); conn.setRequestMethod("POST"); conn.setDoInput(true); conn.setDoOutput(true);
[Code] ....
And here’s what the exception looks like: . . . . . . java.net.SocketException: socket closed at java.net.SocketInputStream.socketRead0(Native Method) at java.net.SocketInputStream.read(SocketInputStream.java:150) at java.net.SocketInputStream.read(SocketInputStream.java:121) at java.io.BufferedInputStream.fill(BufferedInputStream.java:235)
[Code] ....
In my investigation I came across some posts that were mentioning the sockets pool the http connection is keeping, but I’m not sure whether and how this solve the problem I have.
I am trying to create a new text file in FTP Server using FTPClient but im not able to do. By using storeFile method i can only upload file that is already exists in my local system. But my requirement is to create file directly into FTP Server.
Similar to HttpFilter (javax.Servlet.Filter ) which when added in web.xml can intercept any incoming request to JVM / outgoing (as response) independent of framework ( Spring/CXF/Jersy etc ) without any code changes (excluding the filter itself), I am trying to find an API or approach which could intercept any outgoing HTTP calls from JVM to add/modify headers independent of framework.
Quite often the word Outgoing HTTP call is misinterpreted in the forums so let me explain with example.
Let us assume there are two JVMs, jvm1 and jvm2. and there are HTTP calls being made from JVM1 to JVM2. I would like to intercept the HTTP connection being made from JVM1 to modify the headers information before the call happens. I do not want the code to be tied to a specific framework so that I can as bundle the interceptor as a jar and share it with application team. Changes in web.xml is fine.
I'm facing some problem connecting to a IBM 4690 OS Server with the FTPClient class from the commons-net-1.4.1 library. It seems it can't read the folder on the server. The problem is that using the FTP client from Internet Explorer is works perfectly.
Here is my code (kind of hardcoded but it's only to test).
Here is the ParserInitializationException that it throws:
org.apache.commons.net.ftp.parser.ParserInitializationException: Unknown parser type: OS 4690 operating system at org.apache.commons.net.ftp.parser.DefaultFTPFileEntryParserFactory.createFileEntryParser(DefaultFTPFileEntryParserFactory.java:118) at org.apache.commons.net.ftp.FTPClient.initiateListParsing(FTPClient.java:2358) at org.apache.commons.net.ftp.FTPClient.listFiles(FTPClient.java:2141) ...
I've tried to use many of the FTPFileListParser available but without success. How could I handle the problem? Where could I find a Parser that would works?
I am trying to remotely call one servlet and getting below exception:
java.io.StreamCorruptedException: invalid stream header: 3C21444F at java.io.ObjectInputStream.readStreamHeader(ObjectInputStream.java:785) at java.io.ObjectInputStream.<init>(ObjectInputStream.java:282) at com.deere.isg.dm.web.controller.StatsController.getOtherAdminStatsBeanFromConnectURL2(StatsController.java:224) at com.deere.isg.dm.web.controller.StatsController.main(StatsController.java:122)
I'm trying to write a transparent proxy like polipo. Polipo is written in C and I want to have the same result in java.
A simple program that can filter/monitor all connections created and closed by the browser.
To do so, I've chosen to work with sockets, because that's the only way i know to read and write raw data to and from the browser in a completely transparent way.
In this moment my code reads and writes every couple of request/response but I've noticed profiling it that the time needed to create the socket is a bottleneck.
Using URLConnection to create the same connection I need much less time than sockets.
When socket creation implies 50ms URLConnection implies only 1ms.
I've been trying to send a file(text & image files) from one system to another. somewhat I did, but file is not send originally in destination system. It shows AccessDeniedException on the destination system. What should do to avoid this exception.
I am trying to connect a remote machine but I can't. There is a shared folder in the remote machine, when I write the path to file browser in local machine, it does not find the path specified. Both machines have successful network condition and ping each other. Also, the shared folder is opened to everyone, there should not be a permission problem, right?
I have developed a code to connecting remote windows M/C from local M/C by using SSH2 (ganymed-ssh2-build209.jar) API. when I run the code its giving below error. Is there any other way to connect remote windows system using java code.
Exception.
java.io.IOException: There was a problem while talking to <host name>:22 at ch.ethz.ssh2.Connection.connect(Connection.java:642) at ch.ethz.ssh2.Connection.connect(Connection.java:460) at Connect.RemoteServer.ConnectWindowsServer.runCommand(ConnectWindowsServer.java:55) at Connect.RemoteServer.ConnectWindowsServer.main(ConnectWindowsServer.java:27) Caused by: java.net.ConnectException: Connection refused: connect
