Search Results

Search found 16784 results on 672 pages for 'persistent connection'.

Page 225/672 | < Previous Page | 221 222 223 224 225 226 227 228 229 230 231 232  | Next Page >

  • stunnel crashing

    - by Jay
    I'm trying to use stunnel to secure a legacy application's communications. I can't seem to get it setup and working. Can anyone provide any hints where I'm going wrong? Here's what I'm trying to accomplish: A windows service on a client machine connects to a server on port 7000 using TCP. I'd like to encrypt the communication between client and server. Here's what I've tried: Created a new server that accepts ssl connections on port 7443. Got a certificate for the server and installed it. That seems to work with my test setup. Installed stunnel on my windows machine (version 7.43 from the distribution archive file). Installed libssl32.dll and libeay32.dll in the same directory as stunnel.exe ( from the openssl-0.9.8h-1 binary distribution). Installed it as a service using "stunnel -install" Configured stunnel as follows: debug=7 output=C:\p4\internal\Utility\Proxy\proxy.log service=Proxy taskbar=no [exchange] accept=7000 client=yes connect=proxy.blah.com:7443 I changed my hosts file to trick the old application into connecting through stunnel: server.blah.com 127.0.0.1 # when client looks up server it goes to stunnel proxy.blah.com IP-address-of-server.blah.com # stunnel connects to new server "server.blah.com" now resolves to the machine it's running on (i.e. stunnel). "proxy.blah.com" goes to the real server. stunnel should connect to the server. I start the stunnel service and try to connect. It looks like it's working but the stunnel service just shuts down with no message. 2010.04.19 13:16:21 LOG5[4924:3716]: stunnel 4.33 on x86-pc-mingw32-gnu with OpenSSL 0.9.8h 28 May 2008 2010.04.19 13:16:21 LOG5[4924:3716]: Threading:WIN32 SSL:ENGINE Sockets:SELECT,IPv6 2010.04.19 13:16:49 LOG5[4924:3748]: Service exchange accepted connection from 127.0.0.1:4134 2010.04.19 13:16:49 LOG6[4924:3748]: connect_blocking: connecting x.80.60.32:7443 2010.04.19 13:16:49 LOG5[4924:3748]: connect_blocking: connected x.80.60.32:7443 2010.04.19 13:16:49 LOG5[4924:3748]: Service exchange connected remote server from x.253.120.19:4135 2010.04.19 13:20:24 LOG5[3668:3856]: Reading configuration from file stunnel.conf 2010.04.19 13:20:24 LOG7[3668:3856]: Snagged 64 random bytes from C:/.rnd 2010.04.19 13:20:24 LOG7[3668:3856]: Wrote 1024 new random bytes to C:/.rnd 2010.04.19 13:20:24 LOG7[3668:3856]: RAND_status claims sufficient entropy for the PRNG 2010.04.19 13:20:24 LOG7[3668:3856]: PRNG seeded successfully 2010.04.19 13:20:24 LOG7[3668:3856]: SSL context initialized for service exchange 2010.04.19 13:20:24 LOG5[3668:3856]: Configuration successful 2010.04.19 13:20:24 LOG5[3668:3856]: No limit detected for the number of clients 2010.04.19 13:20:24 LOG7[3668:3856]: FD=312 in non-blocking mode 2010.04.19 13:20:24 LOG7[3668:3856]: Option SO_REUSEADDR set on accept socket 2010.04.19 13:20:24 LOG7[3668:3856]: Service exchange bound to 0.0.0.0:7000 2010.04.19 13:20:24 LOG7[3668:3856]: Service exchange opened FD=312 2010.04.19 13:20:24 LOG5[3668:3856]: stunnel 4.33 on x86-pc-mingw32-gnu with OpenSSL 0.9.8h 28 May 2008 2010.04.19 13:20:24 LOG5[3668:3856]: Threading:WIN32 SSL:ENGINE Sockets:SELECT,IPv6 2010.04.19 13:21:02 LOG7[3668:4556]: Service exchange accepted FD=372 from 127.0.0.1:4156 2010.04.19 13:21:02 LOG7[3668:4556]: Creating a new thread 2010.04.19 13:21:02 LOG7[3668:4556]: New thread created 2010.04.19 13:21:02 LOG7[3668:3756]: Service exchange started 2010.04.19 13:21:02 LOG7[3668:3756]: FD=372 in non-blocking mode 2010.04.19 13:21:02 LOG5[3668:3756]: Service exchange accepted connection from 127.0.0.1:4156 2010.04.19 13:21:02 LOG7[3668:3756]: FD=396 in non-blocking mode 2010.04.19 13:21:02 LOG6[3668:3756]: connect_blocking: connecting x.80.60.32:7443 2010.04.19 13:21:02 LOG7[3668:3756]: connect_blocking: s_poll_wait x.80.60.32:7443: waiting 10 seconds 2010.04.19 13:21:02 LOG5[3668:3756]: connect_blocking: connected x.80.60.32:7443 2010.04.19 13:21:02 LOG5[3668:3756]: Service exchange connected remote server from x.253.120.19:4157 2010.04.19 13:21:02 LOG7[3668:3756]: Remote FD=396 initialized 2010.04.19 13:21:02 LOG7[3668:3756]: SSL state (connect): before/connect initialization 2010.04.19 13:21:02 LOG7[3668:3756]: SSL state (connect): SSLv3 write client hello A 2010.04.19 13:21:02 LOG7[3668:3756]: SSL state (connect): SSLv3 read server hello A 2010.04.19 13:21:02 LOG7[3668:3756]: SSL state (connect): SSLv3 read server certificate A 2010.04.19 13:21:02 LOG7[3668:3756]: SSL state (connect): SSLv3 read server done A 2010.04.19 13:21:02 LOG7[3668:3756]: SSL state (connect): SSLv3 write client key exchange A 2010.04.19 13:21:02 LOG7[3668:3756]: SSL state (connect): SSLv3 write change cipher spec A 2010.04.19 13:21:02 LOG7[3668:3756]: SSL state (connect): SSLv3 write finished A 2010.04.19 13:21:02 LOG7[3668:3756]: SSL state (connect): SSLv3 flush data 2010.04.19 13:21:02 LOG7[3668:3756]: SSL state (connect): SSLv3 read finished A The client thinks the connection is closed: No connection could be made because the target machine actively refused it 127.0.0.1:7000 at System.Net.Sockets.Socket.DoConnect(EndPoint endPointSnapshot, SocketAddress socketAddress) at System.Net.Sockets.Socket.Connect(EndPoint remoteEP) at Service.ConnUtility.Connect() Any suggestions?

    Read the article

  • Oracle performance problem

    - by jreid42
    We are using an Oracle 11G machine that is very powerful; has redundant storage etc. It's a beast from what I have been told. We just got this DB for a tool that when I first came on as a coop had like 20 people using, now its upwards of 150 people. I am the only one working on it :( We currently have a system in place that distributes PERL scripts across our entire data center essentially giving us a sort of "grid" computing power. The Perl scripts run a sort of simulation and report back the results to the database. They do selects / inserts. The load is not very high for each script but it could be happening across 20-50 systems at the same time. We then have multiple data centers and users all hitting the same database with this same approach. Our main problem with this is that our database is getting overloaded with connections and having to drop some. We sometimes have upwards of 500 connections. These are old perl scripts and they do not handle this well. Essentially they fail and the results are lost. I would rather avoid having to rewrite a lot of these as they are poorly written, and are a headache to even look at. The database itself is not overloaded, just the connection overhead is too high. We open a connection, make a quick query and then drop the connection. Very short connections but many of them. The database team has basically said we need to lower the number of connections or they are going to ignore us. Because this is distributed across our farm we cant implement persistent connections. I do this with our webserver; but its on a fixed system. The other ones are perl scripts that get opened and closed by the distribution tool and thus arent always running. What would be my best approach to resolving this issue? The scripts themselves can wait for a connection to be open. They do not need to act immediately. Some sort of queing system? I've been suggested to set up a few instances of a tool called "SQL Relay". Maybe one in each data center. How reliable is this tool? How good is this approach? Would it work for what we need? We could have one for each data center and relay requests through it to our main database, keeping a pipeline of open persistent connections? Does this make sense? Is there any other suggestions you can make? Any ideas? Any help would be greatly appreciated. Sadly I am just a coop student working for a very big company and somehow all of this has landed all on my shoulders (there is literally nobody to ask for help; its a hardware company, everybody is hardware engineers, and the database team is useless and in India) and I am quite lost as what the best approach would be? I am extremely overworked and this problem is interfering with on going progress and basically needs to be resolved as quickly as possible; preferably without rewriting the whole system, purchasing hardware (not gonna happen), or shooting myself in the foot. HELP LOL!

    Read the article

  • JMS Step 2 - Using the QueueSend.java Sample Program to Send a Message to a JMS Queue

    - by John-Brown.Evans
    JMS Step 2 - Using the QueueSend.java Sample Program to Send a Message to a JMS Queue .c21_2{vertical-align:top;width:487.3pt;border-style:solid;border-color:#000000;border-width:1pt;padding:5pt 5pt 5pt 5pt} .c15_2{vertical-align:top;width:487.3pt;border-style:solid;border-color:#ffffff;border-width:1pt;padding:5pt 5pt 5pt 5pt} .c0_2{padding-left:0pt;direction:ltr;margin-left:36pt} .c20_2{list-style-type:circle;margin:0;padding:0} .c10_2{list-style-type:disc;margin:0;padding:0} .c6_2{background-color:#ffffff} .c17_2{padding-left:0pt;margin-left:72pt} .c3_2{line-height:1.0;direction:ltr} .c1_2{font-size:10pt;font-family:"Courier New"} .c16_2{color:#1155cc;text-decoration:underline} .c13_2{color:inherit;text-decoration:inherit} .c7_2{background-color:#ffff00} .c9_2{border-collapse:collapse} .c2_2{font-family:"Courier New"} .c18_2{font-size:18pt} .c5_2{font-weight:bold} .c19_2{color:#ff0000} .c12_2{background-color:#f3f3f3;border-style:solid;border-color:#000000;border-width:1pt;} .c14_2{font-size:24pt} .c8_2{direction:ltr;background-color:#ffffff} .c11_2{font-style:italic} .c4_2{height:11pt} .title{padding-top:24pt;line-height:1.15;text-align:left;color:#000000;font-size:36pt;font-family:"Arial";font-weight:bold;padding-bottom:6pt}.subtitle{padding-top:18pt;line-height:1.15;text-align:left;color:#666666;font-style:italic;font-size:24pt;font-family:"Georgia";padding-bottom:4pt} li{color:#000000;font-size:10pt;font-family:"Arial"} p{color:#000000;font-size:10pt;margin:0;font-family:"Arial"} h1{padding-top:0pt;line-height:1.15;text-align:left;color:#888;font-size:24pt;font-family:"Arial";font-weight:normal;padding-bottom:0pt} h2{padding-top:0pt;line-height:1.15;text-align:left;color:#888;font-size:18pt;font-family:"Arial";font-weight:normal;padding-bottom:0pt} h3{padding-top:0pt;line-height:1.15;text-align:left;color:#888;font-size:14pt;font-family:"Arial";font-weight:normal;padding-bottom:0pt} h4{padding-top:0pt;line-height:1.15;text-align:left;color:#888;font-size:12pt;font-family:"Arial";font-weight:normal;padding-bottom:0pt} h5{padding-top:0pt;line-height:1.15;text-align:left;color:#888;font-size:11pt;font-family:"Arial";font-weight:normal;padding-bottom:0pt} h6{padding-top:0pt;line-height:1.15;text-align:left;color:#888;font-size:10pt;font-family:"Arial";font-weight:normal;padding-bottom:0pt} This post is the second in a series of JMS articles which demonstrate how to use JMS queues in a SOA context. In the previous post JMS Step 1 - How to Create a Simple JMS Queue in Weblogic Server 11g I showed you how to create a JMS queue and its dependent objects in WebLogic Server. In this article, we will use a sample program to write a message to that queue. Please review the previous post if you have not created those objects yet, as they will be required later in this example. The previous post also includes useful background information and links to the Oracle documentation for addional research. The following post in this series will show how to read the message from the queue again. 1. Source code The following java code will be used to write a message to the JMS queue. It is based on a sample program provided with the WebLogic Server installation. The sample is not installed by default, but needs to be installed manually using the WebLogic Server Custom Installation option, together with many, other useful samples. You can either copy-paste the following code into your editor, or install all the samples. The knowledge base article in My Oracle Support: How To Install WebLogic Server and JMS Samples in WLS 10.3.x (Doc ID 1499719.1) describes how to install the samples. QueueSend.java package examples.jms.queue; import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.util.Hashtable; import javax.jms.*; import javax.naming.Context; import javax.naming.InitialContext; import javax.naming.NamingException; /** This example shows how to establish a connection * and send messages to the JMS queue. The classes in this * package operate on the same JMS queue. Run the classes together to * witness messages being sent and received, and to browse the queue * for messages. The class is used to send messages to the queue. * * @author Copyright (c) 1999-2005 by BEA Systems, Inc. All Rights Reserved. */ public class QueueSend { // Defines the JNDI context factory. public final static String JNDI_FACTORY="weblogic.jndi.WLInitialContextFactory"; // Defines the JMS context factory. public final static String JMS_FACTORY="jms/TestConnectionFactory"; // Defines the queue. public final static String QUEUE="jms/TestJMSQueue"; private QueueConnectionFactory qconFactory; private QueueConnection qcon; private QueueSession qsession; private QueueSender qsender; private Queue queue; private TextMessage msg; /** * Creates all the necessary objects for sending * messages to a JMS queue. * * @param ctx JNDI initial context * @param queueName name of queue * @exception NamingException if operation cannot be performed * @exception JMSException if JMS fails to initialize due to internal error */ public void init(Context ctx, String queueName) throws NamingException, JMSException { qconFactory = (QueueConnectionFactory) ctx.lookup(JMS_FACTORY); qcon = qconFactory.createQueueConnection(); qsession = qcon.createQueueSession(false, Session.AUTO_ACKNOWLEDGE); queue = (Queue) ctx.lookup(queueName); qsender = qsession.createSender(queue); msg = qsession.createTextMessage(); qcon.start(); } /** * Sends a message to a JMS queue. * * @param message message to be sent * @exception JMSException if JMS fails to send message due to internal error */ public void send(String message) throws JMSException { msg.setText(message); qsender.send(msg); } /** * Closes JMS objects. * @exception JMSException if JMS fails to close objects due to internal error */ public void close() throws JMSException { qsender.close(); qsession.close(); qcon.close(); } /** main() method. * * @param args WebLogic Server URL * @exception Exception if operation fails */ public static void main(String[] args) throws Exception { if (args.length != 1) { System.out.println("Usage: java examples.jms.queue.QueueSend WebLogicURL"); return; } InitialContext ic = getInitialContext(args[0]); QueueSend qs = new QueueSend(); qs.init(ic, QUEUE); readAndSend(qs); qs.close(); } private static void readAndSend(QueueSend qs) throws IOException, JMSException { BufferedReader msgStream = new BufferedReader(new InputStreamReader(System.in)); String line=null; boolean quitNow = false; do { System.out.print("Enter message (\"quit\" to quit): \n"); line = msgStream.readLine(); if (line != null && line.trim().length() != 0) { qs.send(line); System.out.println("JMS Message Sent: "+line+"\n"); quitNow = line.equalsIgnoreCase("quit"); } } while (! quitNow); } private static InitialContext getInitialContext(String url) throws NamingException { Hashtable env = new Hashtable(); env.put(Context.INITIAL_CONTEXT_FACTORY, JNDI_FACTORY); env.put(Context.PROVIDER_URL, url); return new InitialContext(env); } } 2. How to Use This Class 2.1 From the file system on UNIX/Linux Log in to a machine with a WebLogic installation and create a directory to contain the source and code matching the package name, e.g. $HOME/examples/jms/queue. Copy the above QueueSend.java file to this directory. Set the CLASSPATH and environment to match the WebLogic server environment. Go to $MIDDLEWARE_HOME/user_projects/domains/base_domain/bin  and execute . ./setDomainEnv.sh Collect the following information required to run the script: The JNDI name of a JMS queue to use In the Weblogic server console > Services > Messaging > JMS Modules > (Module name, e.g. TestJMSModule) > (JMS queue name, e.g. TestJMSQueue)Select the queue and note its JNDI name, e.g. jms/TestJMSQueue The JNDI name of a connection factory to connect to the queue Follow the same path as above to get the connection factory for the above queue, e.g. TestConnectionFactory and its JNDI namee.g. jms/TestConnectionFactory The URL and port of the WebLogic server running the above queue Check the JMS server for the above queue and the managed server it is targeted to, for example soa_server1. Now find the port this managed server is listening on, by looking at its entry under Environment > Servers in the WLS console, e.g. 8001 The URL for the server to be given to the QueueSend program in this example will therefore be t3://host.domain:8001 e.g. t3://jbevans-lx.de.oracle.com:8001 Edit QueueSend.java and enter the above queue name and connection factory respectively under ...public final static String  JMS_FACTORY=" jms/TestConnectionFactory "; ... public final static String QUEUE=" jms/TestJMSQueue "; ... Compile QueueSend.java using javac QueueSend.java Go to the source’s top-level directory and execute it using java examples.jms.queue.QueueSend t3://jbevans-lx.de.oracle.com:8001 This will prompt for a text input or “quit” to end. In the WLS console, go to the queue and select Monitoring to confirm that a new message was written to the queue. 2.2 From JDeveloper Create a new application in JDeveloper, called, for example JMSTests. When prompted for a project name, enter QueueSend and select Java as the technology Default Package = examples.jms.queue (but you can enter anything here as you will overwrite it in the code later). Leave the other values at their defaults. Press Finish Create a new Java class called QueueSend and use the default values This will create a file called QueueSend.java. Open QueueSend.java, if it is not already open and replace all its contents with the QueueSend java code listed above Some lines might have warnings due to unfound objects. These are due to missing libraries in the JDeveloper project. Add the following libraries to the JDeveloper project: right-click the QueueSend  project in the navigation menu and select Libraries and Classpath , then Add JAR/Directory  Go to the folder containing the JDeveloper installation and find/choose the file javax.jms_1.1.1.jar , e.g. at D:\oracle\jdev11116\modules\javax.jms_1.1.1.jar Do the same for the weblogic.jar file located, for example in D:\oracle\jdev11116\wlserver_10.3\server\lib\weblogic.jar Now you should be able to compile the project, for example by selecting the Make or Rebuild icons   If you try to execute the project, you will get a usage message, as it requires a parameter pointing to the WLS installation containing the JMS queue, for example t3://jbevans-lx.de.oracle.com:8001 . You can automatically pass this parameter to the program from JDeveloper by editing the project’s Run/Debug/Profile. Select the project properties, select Run/Debug/Profile and edit the Default run configuration and add the connection parameter to the Program Arguments field If you execute it again, you will see that it has passed the parameter to the start command If you get a ClassNotFoundException for the class weblogic.jndi.WLInitialContextFactory , then check that the weblogic.jar file was correctly added to the project in one of the earlier steps above. Set the values of JMS_FACTORY and QUEUE the same way as described above in the description of how to use this from a Linux file system, i.e. ...public final static String  JMS_FACTORY=" jms/TestConnectionFactory "; ... public final static String QUEUE=" jms/TestJMSQueue "; ... You need to make one more change to the project. If you execute it now, it will prompt for the payload for the JMS message, but you won’t be able to enter it by default in JDeveloper. You need to enable program input for the project first. Select the project’s properties, then Tool Settings, then check the Allow Program Input checkbox at the bottom and Save. Now when you execute the project, you will get a text entry field at the bottom into which you can enter the payload. You can enter multiple messages until you enter “quit”, which will cause the program to stop. The following screen shot shows the TestJMSQueue’s Monitoring page, after a message was sent to the queue: This concludes the sample. In the following post I will show you how to read the message from the queue again.

    Read the article

  • Apache cyclic redirection problem

    - by slicedlime
    I have an extremely weird problem with one of my sites. I run a number of blogs off a single apache2 server with a shared wordpress install. Each site has a www.domain.com main domain, but a ServerAlias of domain.com. This works fine for all the blogs except one, which instead of redirecting to www.domain.com redirects to domain.com, causing a cyclic redirection. The configuration for each host looks like this: <VirtualHost *:80> ServerName www.domain.com ServerAlias domain.com DocumentRoot "/home/www/www.domain.com" <Directory "/home/www/www.domain.com"> Options MultiViews Indexes Includes FollowSymLinks ExecCGI AllowOverride All Order allow,deny Allow from all </Directory> </VirtualHost> As this didn't work, I tried a mod_rewrite rule for it, which still didn't redirect correctly. The weird thing here is that if i rewrite it to redirect to any other domain it will redirect correctly, even to another subdomain. So a rewrite rule for domain.com that redirects to foo.domain.com works, but not to www.domain.com. In the same way, trying to redirec to www.domain.com/foo/ ends me up with a redirection to domain.com/foo/. Even weirder, I tried setting up domain.com as a completely separate virtual host, and ran this php test script as index.php on it: <?php header('Location: http://www.domain.com/' . $_SERVER["request_uri"]); ?> Hitting domain.com still redirects to domain.com! Checking out the headers sent to the server verifies that I get exactly the redirect URL I wanted, except with the "www." stripped. The same script works like a charm if I replace www. with foo or redirect to any other domain. This has now foiled me for a long time. I've diffed the vhosts configs for a working domain and the faulty one, and the only difference is the domain name itself. I've diffed the .htaccess files for both sites, and the only difference is a path related to the sharing of wordpress installation for the blogs: php_value include_path ".:/home/www/www.domain.com/local/:/home/www/www.domain.com/" I searched through everything in /etc (including apache conf) for the domain name of the faulty host and found nothing weird, searched through everything in /etc for one of the working ones to make sure it didn't differ, I even went so far to check on the DNS setup of two domains to make sure there wasn't anything strange going on. Here's the response for the faulty one: user@localhost dir $ wget -S domain.com --2010-03-20 21:47:24-- http://domain.com/ Resolving domain.com... x.x.x.x Connecting to domain.com|x.x.x.x|:80... connected. HTTP request sent, awaiting response... HTTP/1.1 301 Moved Permanently Via: 1.1 ISA Connection: Keep-Alive Proxy-Connection: Keep-Alive Content-Length: 0 Date: Sat, 20 Mar 2010 20:47:24 GMT Location: http://domain.com/ Content-Type: text/html; charset=UTF-8 Server: Apache X-Powered-By: PHP/5.2.10-pl0-gentoo X-Pingback: http://domain.com/xmlrpc.php Keep-Alive: timeout=15, max=100 Location: http://domain.com/ [following] And a working one: user@localhost dir $ wget -S domain.com --2010-03-20 21:51:33-- http://domain.com/ Resolving domain.com... x.x.x.x Connecting to domain.com|x.x.x.x|:80... connected. HTTP request sent, awaiting response... HTTP/1.1 301 Moved Permanently Via: 1.1 ISA Connection: Keep-Alive Proxy-Connection: Keep-Alive Content-Length: 0 Date: Sat, 20 Mar 2010 20:51:33 GMT Location: http://www.domain.com/ Content-Type: text/html; charset=UTF-8 Server: Apache X-Powered-By: PHP/5.2.10-pl0-gentoo X-Pingback: http://www.domain.com/xmlrpc.php Keep-Alive: timeout=15, max=100 Location: http://www.domain.com/ [following] I'm stumped. I've had this problem for a long time, and I feel like I've tried everything. I can't see why the different domains would act differently under the same installation with the same settings. Help :(

    Read the article

  • Best PHP-based web development 'stack' of 2011

    - by Jens Roland
    I have been building PHP-based web sites for many years, and lately it seems I'm discovering another interesting new tool or method once every few weeks. This begs the question - what is the current state of the art in PHP development stacks for the seasoned coder? I'm specifically interested in the following: High-performance web server Database MVC framework Build tool Revision control Continuous Integration Automated testing Non-persistent caching I'd like to optimize my stack for scalability and rapid development. I'm not looking for personal preference here, I'm looking for real, quantifiable reasons to pick this-over-that.

    Read the article

  • It is possible to hibernate an LXC container?

    - by Jo-Erlend Schinstad
    I know about lxc-freeze and lxc-unfreeze, but as I understand it, these simply pauses the container, similar to sending SIGSTOP and SIGCONT to a process. If I reboot the host, then the containers will cease to exist, right? I would really like a way to save state to persistent storage so that I could resume them at some later time, even the host is rebooted or something like that. I can achieve exactly what I want using VirtualBox by using the "Save machine state" mechanism, but if I could do it with LXC, it would be completely awesome.

    Read the article

  • how to improve concepts for interview

    - by Rahul Mehta
    Hi, I had given the interview , and interviewer tell me to improve the concepts , e.g. he ask me type of array ,and i answered two types of array simple array and associative array . e.g. 2 he ask me why you use pdo , and i answered we can use any database e.g. oracle , mysql and it helps in sql injection , then he ask me how it helps in sql injection then i was not having correct answer. e.g. 3 he ask me about persistent connection , i just use the mysql_pconnect i dont where it will be used and how . is there is any standard way to follow to improve concepts. Please suggest . Thanks

    Read the article

  • Master Data Management Implementation Styles

    - by david.butler(at)oracle.com
    In any Master Data Management solution deployment, one of the key decisions to be made is the choice of the MDM architecture. Gartner and other analysts describe some different Hub deployment styles, which must be supported by a best of breed MDM solution in order to guarantee the success of the deployment project.   Registry Style: In a Registry Style MDM Hub, the various source systems publish their data and a subscribing Hub stores only the source system IDs, the Foreign Keys (record IDs on source systems) and the key data values needed for matching. The Hub runs the cleansing and matching algorithms and assigns unique global identifiers to the matched records, but does not send any data back to the source systems. The Registry Style MDM Hub uses data federation capabilities to build the "virtual" golden view of the master entity from the connected systems.   Consolidation Style: The Consolidation Style MDM Hub has a physically instantiated, "golden" record stored in the central Hub. The authoring of the data remains distributed across the spoke systems and the master data can be updated based on events, but is not guaranteed to be up to date. The master data in this case is usually not used for transactions, but rather supports reporting; however, it can also be used for reference operationally.   Coexistence Style: The Coexistence Style MDM Hub involves master data that's authored and stored in numerous spoke systems, but includes a physically instantiated golden record in the central Hub and harmonized master data across the application portfolio. The golden record is constructed in the same manner as in the consolidation style, and, in the operational world, Consolidation Style MDM Hubs often evolve into the Coexistence Style. The key difference is that in this architectural style the master data stored in the central MDM system is selectively published out to the subscribing spoke systems.   Transaction Style: In this architecture, the Hub stores, enhances and maintains all the relevant (master) data attributes. It becomes the authoritative source of truth and publishes this valuable information back to the respective source systems. The Hub publishes and writes back the various data elements to the source systems after the linking, cleansing, matching and enriching algorithms have done their work. Upstream, transactional applications can read master data from the MDM Hub, and, potentially, all spoke systems subscribe to updates published from the central system in a form of harmonization. The Hub needs to support merging of master records. Security and visibility policies at the data attribute level need to be supported by the Transaction Style hub, as well.   Adaptive Transaction Style: This is similar to the Transaction Style, but additionally provides the capability to respond to diverse information and process requests across the enterprise. This style emerged most recently to address the limitations of the above approaches. With the Adaptive Transaction Style, the Hub is built as a platform for consolidating data from disparate third party and internal sources and for serving unified master entity views to operational applications, analytical systems or both. This approach delivers a real-time Hub that has a reliable, persistent foundation of master reference and relationship data, along with all the history and lineage of data changes needed for audit and compliance tracking. On top of this persistent master data foundation, the Hub can dynamically aggregate transaction data on demand from different source systems to deliver the unified golden view to downstream systems. Data can also be accessed through batch interfaces, published to a message bus or served through a real-time services layer. New data sources can be readily added in this approach by extending the data model and by configuring the new source mappings and the survivorship rules, meaning that all legacy data hubs can be leveraged to contribute their records/rules into the new transaction hub. Finally, through rich user interfaces for data stewardship, it allows exception handling by business analysts to keep it current with business rules/practices while maintaining the reliability of best-of-breed master records.   Confederation Style: In this architectural style, several Hubs are maintained at departmental and/or agency and/or territorial level, and each of them are connected to the other Hubs either directly or via a central Super-Hub. Each Domain level Hub can be implemented using any of the previously described styles, but normally the Central Super-Hub is a Registry Style one. This is particularly important for Public Sector organizations, where most of the time it is practically or legally impossible to store in a single central hub all the relevant constituent information from all departments.   Oracle MDM Solutions can be deployed according to any of the above MDM architectural styles, and have been specifically designed to fully support the Transaction and Adaptive Transaction styles. Oracle MDM Solutions provide strong data federation and integration capabilities which are key to enabling the use of the Confederated Hub as a possible architectural style approach. Don't lock yourself into a solution that cannot evolve with your needs. With Oracle's support for any type of deployment architecture, its ability to leverage the outstanding capabilities of the Oracle technology stack, and its open interfaces for non-Oracle technology stacks, Oracle MDM Solutions provide a low TCO and a quick ROI by enabling a phased implementation strategy.

    Read the article

  • PXE Boot not working

    - by Nishant
    Please explain the error in this screenshot DHCP Setting: This screenshot was taken after powering off the old comp hence he server interface is shown as the wireless card - it becomes 192.168.0.1 when I connect wires and power up the old laptop to boot via PXE. My scenario is simple. An old laptop and a new laptop . A cross over cable ( that I myself made from CAT 6 cable by cutting it and connecting 4 wires as mentioned in some doc). The new laptop ( tftp server ) has a Wirelss Card ( with which I am browsing and writing this ) . And the cable is connected between laptops . TFTP server ( new laptop details ) Windows IP Configuration Ethernet adapter Local Area Connection: Connection-specific DNS Suffix . : Link-local IPv6 Address . . . . . : fe80::f511:3d4a:ca01:122e%16 IPv4 Address. . . . . . . . . . . : 192.168.0.1 Subnet Mask . . . . . . . . . . . : 255.255.255.0 Default Gateway . . . . . . . . . : 192.168.0.2 Wireless LAN adapter Wireless Network Connection: Connection-specific DNS Suffix . : Achilles Link-local IPv6 Address . . . . . : fe80::99b1:8ae0:9e6c:f300%11 IPv4 Address. . . . . . . . . . . : 192.168.2.3 Subnet Mask . . . . . . . . . . . : 255.255.255.0 Default Gateway . . . . . . . . . : 192.168.2.1

    Read the article

  • How to use RDP protocol in Remote Desktop Viewer?

    - by drgrog
    I am using a Natty Live-USB, and the Remote Desktop Viewer application (Applications - Internet - Remote Desktop Viewer) only shows SSH & VNC protocols. How can I include RDP in the list, in order to connect to existing Windows Remote Desktop sessions on Windows XP machines. I am aware that I can use the gnome-rdp application, or even rdesktop hostname from a terminal, but I would like to create a persistent LiveUSB that uses Remote Desktop Viewer to connect to Windows RDP (port 3389). I do not want to set up VNC, TeamViewer or any others, as these do not solve my problem due to the fact they need additional software on the remote hosts.

    Read the article

  • Examples of Liskov Substitution

    - by james lewis
    I'm facilitating a session next week on the Liskov Substitution Principle and I was wondering if anyone had any examples of violations 'from the trenches'? I'm looking for something other than uncle Bob's rectangle - square problem and the persistent set problem he talks about in A-PPP (although that is a great example). So far I'm using the example of a (very simple) List and an IndexedList as the 'correct' use of inheritance. And the addition of a Set to this hierarchy as a violation (as a Set is distinct; strengthening the pre condition of the Add method). I've also taken this great example and it's solution from this question Both those examples are great but I'm looking for something more subtle and harder to spot. So far I've come up with nothing so if you've got a great, subtle example post it up. Also, any metaphors you've come across that helped you understand LSP would be really useful too.

    Read the article

  • Sound unavailable every other session

    - by Oxwivi
    On my desktop running Oneiric, sometimes there's no sound at all, but it would work normally at other times. My setup is built ground-up from minimal Ubuntu, but since sounds work fine, at times, I don't think it is a backend dependency issue. When it works, it will play anything from regular audio files and movies to YouTube Flash players. For the record, I installed LXDE with the alsa-base and alsa-utils packages which are the only audio-related dependencies for the lubuntu-desktop. For a while, I also used persistent Oneiric live USB, and do not recall any sound issues. It's one thing to not play sound entirely, but playing sound only under some very unclear circumstances is something else. Please help me diagnose it.

    Read the article

  • Include Method Extension for IObjectSet What about the mocks?

    Eager loading with Entity Framework depends on the special ObjectQuery.Include method. We’ve had that from Day 1 (first version of ef). Now we use ObjectSets in EF4 which inherit from ObjectQuery (thereby inheriting Include) and also implement IObjectSet. IObjectSet allows us to break the queries apart from ObjectQuery and ObjectContext so we can write persistent ignorant, testable code. But IObjectSet doesn’t come with the Include method and you have to create an extension method to...Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

    Read the article

  • All client browsers repeatedly asking for NTLM authentication when running through local proxy server

    - by Marko
    All client browsers repeatedly asking for NTLM authentication when running through local proxy server. When pointing browsers through the local proxy to the internet, some but not all clients are being repeatedley prompted to authenticate to the proxy server. I have inspected the headers using firefox live headers as well as fiddler, and in all cases the authentication prompts happen when requesting SSL resources. an example of this would be as follows: GET http://gmail.google.com/mail/ HTTP/1.1 Accept: image/gif, image/jpeg, image/pjpeg, image/pjpeg, application/x-shockwave- flash, application/x-ms-application, application/x-ms-xbap, application/vnd.ms- xpsdocument, application/xaml+xml, */* Accept-Language: en-gb User-Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.1; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729) Accept-Encoding: gzip, deflate Proxy-Connection: Keep-Alive Host: gmail.google.com GET http://gmail.google.com/mail/ HTTP/1.1 Accept: image/gif, image/jpeg, image/pjpeg, image/pjpeg, application/x-shockwave- flash, application/x-ms-application, application/x-ms-xbap, application/vnd.ms- xpsdocument, application/xaml+xml, */* Accept-Language: en-gb User-Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.1; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729) Accept-Encoding: gzip, deflate Proxy-Connection: Keep-Alive Host: gmail.google.com Proxy-Authorization: NTLM TlRMTVNTUAABAAAAB7IIogkACQAvAAAABwAHACgAAAAFASgKAAAAD1dJTlhQMUdGTEFHU0hJUDc= GET http://gmail.google.com/mail/ HTTP/1.1 Accept: image/gif, image/jpeg, image/pjpeg, image/pjpeg, application/x-shockwave- flash, application/x-ms-application, application/x-ms-xbap, application/vnd.ms- xpsdocument, application/xaml+xml, */* Accept-Language: en-gb User-Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.1; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729) Accept-Encoding: gzip, deflate Proxy-Connection: Keep-Alive Proxy-Authorization: NTLM TlRMTVNTUAADA (more stuff goes here I cut it short) Host: gmail.google.com At this point the username and password prompt has appeared in the browser, it does not matter what is typed into this box, correct credentials, random nonsense the browser does not accept anything in this box it will continue to popup. If I press cancel, I sometimes get a http 407 error, but on other occasions I click cancel the website proceeds to download and show normally. This is repeatable with some clients running through my proxy server, but in other cases it does not happen at all. In the cases where a client computer works normally, the only difference I can see is that the 3rd request for SSL resource comes back with a 200 response, see below: CONNECT gmail.google.com:443 HTTP/1.0 User-Agent: Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0; MALC) Proxy-Connection: Keep-Alive Content-Length: 0 Host: gmail.google.com Pragma: no-cache Proxy-Authorization: NTLM TlRMTVNTUAADAAAAGAAYAIAAAA A SSLv3-compatible ClientHello handshake was found. I have tried resetting user accounts as well as computer accounts in Active Directory. User accounts and passwords that are being used are correct and the passwords have been reset so they are not out of sync. I have removed the clients and even the proxy server from the domain, and rejoined them. I have installed a complete separate proxy server and get exactly the same problem when I point clients to a different proxy server on a different IP address.

    Read the article

  • New Oracle Information Rights Management release (11.1.1.3)

    - by Simon Thorpe
    Just released is the latest version of the market leading document security technology from Oracle. Oracle IRM 11g is the result of over 12 years of development and innovation to allow customers to provide persistent security to their most confidential documents and emails. This latest release continues our refinement of the technology and features the following; Continued improvements to the web based Oracle IRM Management Website New features in the out of the box classification model New Java APIs improving application integration support Support for DB2 as the IRM database. Over the coming months we will see more releases from this technology as we improve format support, platform support and continue the strategy to for Oracle IRM as the most secure, scalable and usable document security solution in the market. Want to learn more about Oracle IRM? View our video presentation and demonstration or try using it for your self via our simple online self service demo. Keep up to date on Oracle via this blog or on our Twitter, YouTube and Facebook pages.

    Read the article

  • Ubuntu live session crashes and boots to a black screen

    - by Bsc
    I heard about Ubuntu from a friend and wanted to test it out. I made a Pendrive Ubuntu 12.04 with a persistent file using Universal USB Installer. The first time I booted Ubuntu from the USB everything went like usual. I was just a bit exploring Ubuntu and had installed a few apps nothing more. Today after using Windows 7 for while again, I wanted to boot Ubuntu again. When I boot it, the usual loading screen comes up but after that it crashes and gave me a black screen. Is there a possibility to check the USB on errors or do I need to reinstall Ubuntu on the USB?

    Read the article

  • Level and Player objects - which should contain which?

    - by Thane Brimhall
    I've been working on a several simple games, and I've always come to a decision point where I have to choose whether to have the Level object as an attribute of the Player class or the Player as an attribute of the Level class. I can see arguments for both: The Level should contain the player because it also contains every other entity. In fact it just makes sense this way: "John is in the room." It makes it a bit more difficult to move the player to a new level, however, because then each level has to pass its player object to an upcoming level. On the other hand, it makes programming sense to me to leave the player as the top-level object that is persistent between levels, and the environment changes because the player decides to change his level and location. It becomes very easy to change levels, because all I have to do is replace the level variable on the player. What's the most common practice here? Or better yet, is there a "right" way to architecture this relationship?

    Read the article

  • Getting Started on Isometric Board Game port

    - by Jehosephat
    I have developed a (off-line) board game that I would like to translate to an online/social game in an isometric grid perspective. My background is in .NET web development, so I'm very comfortable with C#, HTML, jQuery/javascript. Still getting my feet wet with HTML5. I have familiarity with Flash, but I haven't worked with it in years. I'm also interested in working with Azure for hosting the back-end. Ultimately I'd like this game to have persistent leaderboard/achievements and therefore be able to log in through FB and Kong and the like. Obviously, I'm not looking for 'here's exactly how to do all of this'. But I would love some opinions on where to start, particularly given my background and goals. Would be happy to share more details if it makes answering easier! Thanks!

    Read the article

  • How to show other characters in online 2D rpg

    - by Loligans
    I have Player 1 and Player 2 I am using Json to send and retrieve player data between the client and the server, but when another player logs in, and is in the same map, how would I send that data to both players to update the graphics engine to show there are 2 Players on the map? About my game it is a 2D RPG tile based game it is 24x15 Tiles it is Real time Action it should interact anywhere between 10-150 ping players interact with each other when in the same map and can see each other moving around the game world is persistent, and is saved when the server shuts down Right now the server just sends the player Only their information which is inside a Json Object Here is an example of what I am talking about If you notice there are 2 separate characters in 2 separate clients, but they are running on the same server. I am trying to get them to show up on both clients, but I don't know how I should accomplish this. Should I send it as an added value in the Json object? Also what is the name of this process so I can look it up and find more info on it?

    Read the article

  • Google I/O 2010 - Making smart & scalable Wave robots

    Google I/O 2010 - Making smart & scalable Wave robots Google I/O 2010 - Making smart & scalable Wave robots Wave 201 David Byttow, Marcel Prasetya A smart robot must be able to store persistent data. Wave robots can store data in wave structures, like wavelets, datadocs, and annotations, instead of traditional datastores. A scalable robot must perform operations with minimal bandwidth. Wave robots can optimize by selecting the appropriate amount of context, the optimal events, and narrow filters for events. In this talk, we'll share best practices on data storage and scaling. For all I/O 2010 sessions, please go to code.google.com From: GoogleDevelopers Views: 9 0 ratings Time: 58:25 More in Science & Technology

    Read the article

  • stunnel crashing

    - by Jay
    I'm trying to use stunnel to secure a legacy application's communications. I can't seem to get it setup and working. Can anyone provide any hints where I'm going wrong? Here's what I'm trying to accomplish: A windows service on a client machine connects to a server on port 7000 using TCP. I'd like to encrypt the communication between client and server. Here's what I've tried: Created a new server that accepts ssl connections on port 7443. Got a certificate for the server and installed it. That seems to work with my test setup. Installed stunnel on my windows machine (version 7.43 from the distribution archive file). Installed libssl32.dll and libeay32.dll in the same directory as stunnel.exe ( from the openssl-0.9.8h-1 binary distribution). Installed it as a service using "stunnel -install" Configured stunnel as follows: debug=7 output=C:\p4\internal\Utility\Proxy\proxy.log service=Proxy taskbar=no [exchange] accept=7000 client=yes connect=proxy.blah.com:7443 I changed my hosts file to trick the old application into connecting through stunnel: server.blah.com 127.0.0.1 # when client looks up server it goes to stunnel proxy.blah.com IP-address-of-server.blah.com # stunnel connects to new server "server.blah.com" now resolves to the machine it's running on (i.e. stunnel). "proxy.blah.com" goes to the real server. stunnel should connect to the server. I start the stunnel service and try to connect. It looks like it's working but the stunnel service just shuts down with no message. 2010.04.19 13:16:21 LOG5[4924:3716]: stunnel 4.33 on x86-pc-mingw32-gnu with OpenSSL 0.9.8h 28 May 2008 2010.04.19 13:16:21 LOG5[4924:3716]: Threading:WIN32 SSL:ENGINE Sockets:SELECT,IPv6 2010.04.19 13:16:49 LOG5[4924:3748]: Service exchange accepted connection from 127.0.0.1:4134 2010.04.19 13:16:49 LOG6[4924:3748]: connect_blocking: connecting x.80.60.32:7443 2010.04.19 13:16:49 LOG5[4924:3748]: connect_blocking: connected x.80.60.32:7443 2010.04.19 13:16:49 LOG5[4924:3748]: Service exchange connected remote server from x.253.120.19:4135 2010.04.19 13:20:24 LOG5[3668:3856]: Reading configuration from file stunnel.conf 2010.04.19 13:20:24 LOG7[3668:3856]: Snagged 64 random bytes from C:/.rnd 2010.04.19 13:20:24 LOG7[3668:3856]: Wrote 1024 new random bytes to C:/.rnd 2010.04.19 13:20:24 LOG7[3668:3856]: RAND_status claims sufficient entropy for the PRNG 2010.04.19 13:20:24 LOG7[3668:3856]: PRNG seeded successfully 2010.04.19 13:20:24 LOG7[3668:3856]: SSL context initialized for service exchange 2010.04.19 13:20:24 LOG5[3668:3856]: Configuration successful 2010.04.19 13:20:24 LOG5[3668:3856]: No limit detected for the number of clients 2010.04.19 13:20:24 LOG7[3668:3856]: FD=312 in non-blocking mode 2010.04.19 13:20:24 LOG7[3668:3856]: Option SO_REUSEADDR set on accept socket 2010.04.19 13:20:24 LOG7[3668:3856]: Service exchange bound to 0.0.0.0:7000 2010.04.19 13:20:24 LOG7[3668:3856]: Service exchange opened FD=312 2010.04.19 13:20:24 LOG5[3668:3856]: stunnel 4.33 on x86-pc-mingw32-gnu with OpenSSL 0.9.8h 28 May 2008 2010.04.19 13:20:24 LOG5[3668:3856]: Threading:WIN32 SSL:ENGINE Sockets:SELECT,IPv6 2010.04.19 13:21:02 LOG7[3668:4556]: Service exchange accepted FD=372 from 127.0.0.1:4156 2010.04.19 13:21:02 LOG7[3668:4556]: Creating a new thread 2010.04.19 13:21:02 LOG7[3668:4556]: New thread created 2010.04.19 13:21:02 LOG7[3668:3756]: Service exchange started 2010.04.19 13:21:02 LOG7[3668:3756]: FD=372 in non-blocking mode 2010.04.19 13:21:02 LOG5[3668:3756]: Service exchange accepted connection from 127.0.0.1:4156 2010.04.19 13:21:02 LOG7[3668:3756]: FD=396 in non-blocking mode 2010.04.19 13:21:02 LOG6[3668:3756]: connect_blocking: connecting x.80.60.32:7443 2010.04.19 13:21:02 LOG7[3668:3756]: connect_blocking: s_poll_wait x.80.60.32:7443: waiting 10 seconds 2010.04.19 13:21:02 LOG5[3668:3756]: connect_blocking: connected x.80.60.32:7443 2010.04.19 13:21:02 LOG5[3668:3756]: Service exchange connected remote server from x.253.120.19:4157 2010.04.19 13:21:02 LOG7[3668:3756]: Remote FD=396 initialized 2010.04.19 13:21:02 LOG7[3668:3756]: SSL state (connect): before/connect initialization 2010.04.19 13:21:02 LOG7[3668:3756]: SSL state (connect): SSLv3 write client hello A 2010.04.19 13:21:02 LOG7[3668:3756]: SSL state (connect): SSLv3 read server hello A 2010.04.19 13:21:02 LOG7[3668:3756]: SSL state (connect): SSLv3 read server certificate A 2010.04.19 13:21:02 LOG7[3668:3756]: SSL state (connect): SSLv3 read server done A 2010.04.19 13:21:02 LOG7[3668:3756]: SSL state (connect): SSLv3 write client key exchange A 2010.04.19 13:21:02 LOG7[3668:3756]: SSL state (connect): SSLv3 write change cipher spec A 2010.04.19 13:21:02 LOG7[3668:3756]: SSL state (connect): SSLv3 write finished A 2010.04.19 13:21:02 LOG7[3668:3756]: SSL state (connect): SSLv3 flush data 2010.04.19 13:21:02 LOG7[3668:3756]: SSL state (connect): SSLv3 read finished A The client thinks the connection is closed: No connection could be made because the target machine actively refused it 127.0.0.1:7000 at System.Net.Sockets.Socket.DoConnect(EndPoint endPointSnapshot, SocketAddress socketAddress) at System.Net.Sockets.Socket.Connect(EndPoint remoteEP) at Service.ConnUtility.Connect() Any suggestions?

    Read the article

  • iOS persistant storage with update function

    - by jernej
    im developing a game which has different levels and i need to store all levels and its elements (position, image, sounds,..) into a file/database. The levels will be updated so i need a function that checks online for a update and downloads a database dump and additional files. I was planing to store all the persistent data into a SQLLite database, but not quite sure how to do the update part - to pack the database dump and the files together (in a .zip or with a xml). Can this be done any other way (as secure as possible)? thanks!

    Read the article

  • Suspend fails (reboot on resume) and no hibernate option

    - by Matt Kibble
    Upgraded from 10.04 to 10.10 removed hibernate option for me and introduced the problem where by after entering standby (being indicated by blinking amber LED on my laptop) I cannot resume my session. Instead I get a crash and system reboots (crash comes instantly on trying to resume). Tried clean install to eliminate possibility of an upgrade issue but its still persistent. All latest updates installed. Tried looking for an answer to this but still no joy. Laptop is Sony VGN-FW41E.

    Read the article

  • Why can't I ping server? VMware set to 'Bridged' loses IP address

    - by Dave
    I have installed a fresh 10.04 server onto a laptop on a home network as a VMware machine and set network connection to 'Bridged: connect directly to the physical network' from within VMware and rebooted the server. It then loses its IP address. dhclient eth0 says "No working leases in persistent database - sleeping" DHCP is working fine on the wi-fi router. The laptop is wired to a wireless router and from there wirelessly to a desktop. Desktop and Laptop can ping each other from Windows. I can ping the VM from Windows on the same laptop, but not from the desktop. Strangely ping has started to resolve hostnames to IPv6 addresses and not IPv4. Don't know whether that's connected? A kick in the right direction would be greatly appreciated. I've been an Ubuntu desktkop user for a few years, but new to ubuntu servers.

    Read the article

  • Optimizing a thread safe Java NIO / Serialization / FIFO Queue [migrated]

    - by trialcodr
    I've written a thread safe, persistent FIFO for Serializable items. The reason for reinventing the wheel is that we simply can't afford any third party dependencies in this project and want to keep this really simple. The problem is it isn't fast enough. Most of it is undoubtedly due to reading and writing directly to disk but I think we should be able to squeeze a bit more out of it anyway. Any ideas on how to improve the performance of the 'take'- and 'add'-methods? /** * <code>DiskQueue</code> Persistent, thread safe FIFO queue for * <code>Serializable</code> items. */ public class DiskQueue<ItemT extends Serializable> { public static final int EMPTY_OFFS = -1; public static final int LONG_SIZE = 8; public static final int HEADER_SIZE = LONG_SIZE * 2; private InputStream inputStream; private OutputStream outputStream; private RandomAccessFile file; private FileChannel channel; private long offs = EMPTY_OFFS; private long size = 0; public DiskQueue(String filename) { try { boolean fileExists = new File(filename).exists(); file = new RandomAccessFile(filename, "rwd"); if (fileExists) { size = file.readLong(); offs = file.readLong(); } else { file.writeLong(size); file.writeLong(offs); } } catch (FileNotFoundException e) { throw new RuntimeException(e); } catch (IOException e) { throw new RuntimeException(e); } channel = file.getChannel(); inputStream = Channels.newInputStream(channel); outputStream = Channels.newOutputStream(channel); } /** * Add item to end of queue. */ public void add(ItemT item) { try { synchronized (this) { channel.position(channel.size()); ObjectOutputStream s = new ObjectOutputStream(outputStream); s.writeObject(item); s.flush(); size++; file.seek(0); file.writeLong(size); if (offs == EMPTY_OFFS) { offs = HEADER_SIZE; file.writeLong(offs); } notify(); } } catch (IOException e) { throw new RuntimeException(e); } } /** * Clears overhead by moving the remaining items up and shortening the file. */ public synchronized void defrag() { if (offs > HEADER_SIZE && size > 0) { try { long totalBytes = channel.size() - offs; ByteBuffer buffer = ByteBuffer.allocateDirect((int) totalBytes); channel.position(offs); for (int bytes = 0; bytes < totalBytes;) { int res = channel.read(buffer); if (res == -1) { throw new IOException("Failed to read data into buffer"); } bytes += res; } channel.position(HEADER_SIZE); buffer.flip(); for (int bytes = 0; bytes < totalBytes;) { int res = channel.write(buffer); if (res == -1) { throw new IOException("Failed to write buffer to file"); } bytes += res; } offs = HEADER_SIZE; file.seek(LONG_SIZE); file.writeLong(offs); file.setLength(HEADER_SIZE + totalBytes); } catch (IOException e) { throw new RuntimeException(e); } } } /** * Returns the queue overhead in bytes. */ public synchronized long overhead() { return (offs == EMPTY_OFFS) ? 0 : offs - HEADER_SIZE; } /** * Returns the first item in the queue, blocks if queue is empty. */ public ItemT peek() throws InterruptedException { block(); synchronized (this) { if (offs != EMPTY_OFFS) { return readItem(); } } return peek(); } /** * Returns the number of remaining items in queue. */ public synchronized long size() { return size; } /** * Removes and returns the first item in the queue, blocks if queue is empty. */ public ItemT take() throws InterruptedException { block(); try { synchronized (this) { if (offs != EMPTY_OFFS) { ItemT result = readItem(); size--; offs = channel.position(); file.seek(0); if (offs == channel.size()) { truncate(); } file.writeLong(size); file.writeLong(offs); return result; } } return take(); } catch (IOException e) { throw new RuntimeException(e); } } /** * Throw away all items and reset the file. */ public synchronized void truncate() { try { offs = EMPTY_OFFS; file.setLength(HEADER_SIZE); size = 0; } catch (IOException e) { throw new RuntimeException(e); } } /** * Block until an item is available. */ protected void block() throws InterruptedException { while (offs == EMPTY_OFFS) { try { synchronized (this) { wait(); file.seek(LONG_SIZE); offs = file.readLong(); } } catch (IOException e) { throw new RuntimeException(e); } } } /** * Read and return item. */ @SuppressWarnings("unchecked") protected ItemT readItem() { try { channel.position(offs); return (ItemT) new ObjectInputStream(inputStream).readObject(); } catch (ClassNotFoundException e) { throw new RuntimeException(e); } catch (IOException e) { throw new RuntimeException(e); } } }

    Read the article

< Previous Page | 221 222 223 224 225 226 227 228 229 230 231 232  | Next Page >