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• JSF library for Master - Details screen

  - by user305702

  I have a JSF - Spring - iBatis Technical stack I need to create Master Details relationship screen with two level of Master _Details captured in single screen Which JSF library gives support for such requirements ??? Exact Need : Have to create at least 5-6 screens with Header- Line - LineItemDetails - LineTaxDetails - LineXYZDetails in single screen Please help with examples or urls regards Shridhar

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• Using QoS to prioritize IP addresses

  - by Tristan

  I have a Western Digital N900 router. I was hoping I'd be able to throttle users based on their MAC address with it, which isn't possible sadly. Seems simple in principle though, duh. The battle against bandwidth hogging roomates rages on. Could I just set the local IP range to their IP, and then set the Local port range to every single port in existence. Then prioritize their IP to lower than mine? Will this work? What are all the ports? And what's the difference between Local and Remote IPs or Ports? Name: Roomate, Priority: Low, Protocol: TCP or UDP ??, Local IP Range: .101 to .101, Local Port Range: 0 to infinity, Remote IP Range: ? to ?, Remote Port Range: ? to ?

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• How to send audio data from Java Applet to Rails controller

  - by cooldude

  Hi, I have to send the audio data in byte array obtain by recording from java applet at the client side to rails server at the controller in order to save. So, what encoding parameters at the applet side be used and in what form the audio data be converted like String or byte array so that rails correctly recieve data and then I can save that data at the rails in the file. As currently the audio file made by rails controller is not playing. It is the following ERROR : LAVF_header: av_open_input_stream() failed while playing with the mplayer. Here is the Java Code: package networksocket; import java.util.logging.Level; import java.util.logging.Logger; import javax.swing.JApplet; import java.net.*; import java.io.*; import java.awt.event.*; import java.awt.*; import java.sql.*; import javax.swing.*; import javax.swing.border.*; import java.awt.*; import java.util.Properties; import javax.swing.plaf.basic.BasicSplitPaneUI.BasicHorizontalLayoutManager; import sun.awt.HorizBagLayout; import sun.awt.VerticalBagLayout; import sun.misc.BASE64Encoder; /** * * @author mukand */ public class Urlconnection extends JApplet implements ActionListener { /** * Initialization method that will be called after the applet is loaded * into the browser. */ public BufferedInputStream in; public BufferedOutputStream out; public String line; public FileOutputStream file; public int bytesread; public int toread=1024; byte b[]= new byte[toread]; public String f="FINISH"; public String match; public File fileopen; public JTextArea jTextArea; public Button refreshButton; public HttpURLConnection urlConn; public URL url; OutputStreamWriter wr; BufferedReader rd; @Override public void init() { // TODO start asynchronous download of heavy resources //textField= new TextField("START"); //getContentPane().add(textField); JPanel p = new JPanel(); jTextArea= new JTextArea(1500,1500); p.setLayout(new GridLayout(1,1, 1,1)); p.add(new JLabel("Server Details")); p.add(jTextArea); Container content = getContentPane(); content.setLayout(new GridBagLayout()); // Used to center the panel content.add(p); jTextArea.setLineWrap(true); refreshButton = new java.awt.Button("Refresh"); refreshButton.reshape(287,49,71,23); refreshButton.setFont(new Font("Dialog", Font.PLAIN, 12)); refreshButton.addActionListener(this); add(refreshButton); Properties properties = System.getProperties(); properties.put("http.proxyHost", "netmon.iitb.ac.in"); properties.put("http.proxyPort", "80"); } @Override public void actionPerformed(ActionEvent e) { try { url = new URL("http://localhost:3000/audio/audiorecieve"); urlConn = (HttpURLConnection)url.openConnection(); //String login = "mukandagarwal:rammstein$"; //String encodedLogin = new BASE64Encoder().encodeBuffer(login.getBytes()); //urlConn.setRequestProperty("Proxy-Authorization",login); urlConn.setRequestMethod("POST"); // urlConn.setRequestProperty("Content-Type", //"application/octet-stream"); //urlConn.setRequestProperty("Content-Type","audio/mpeg");//"application/x-www- form-urlencoded"); //urlConn.setRequestProperty("Content-Type","application/x-www- form-urlencoded"); //urlConn.setRequestProperty("Content-Length", "" + // Integer.toString(urlParameters.getBytes().length)); urlConn.setRequestProperty("Content-Language", "UTF-8"); urlConn.setDoOutput(true); urlConn.setDoInput(true); byte bread[]=new byte[2048]; int iread; char c; String data=URLEncoder.encode("key1", "UTF-8")+ "="; //String data="key1="; FileInputStream fileread= new FileInputStream("//home//mukand//Hellion.ogg");//Dogs.mp3");//Desktop//mausam1.mp3"); while((iread=fileread.read(bread))!=-1) { //data+=(new String()); /*for(int i=0;i<iread;i++) { //c=(char)bread[i]; System.out.println(bread[i]); }*/ data+= URLEncoder.encode(new String(bread,iread), "UTF-8");//new String(new String(bread));// // data+=new String(bread,iread); } //urlConn.setRequestProperty("Content-Length",Integer.toString(data.getBytes().length)); System.out.println(data); //data+=URLEncoder.encode("mukand", "UTF-8"); //data += "&" + URLEncoder.encode("key2", "UTF-8") + "=" + URLEncoder.encode("value2", "UTF-8"); //data="key1="; wr = new OutputStreamWriter(urlConn.getOutputStream());//urlConn.getOutputStream(); //if((iread=fileread.read(bread))!=-1) // wr.write(bread,0,iread); wr.write(data); wr.flush(); fileread.close(); jTextArea.append("Send"); // Get the response rd = new BufferedReader(new InputStreamReader(urlConn.getInputStream())); while ((line = rd.readLine()) != null) { jTextArea.append(line); } wr.close(); rd.close(); //jTextArea.append("click"); } catch (MalformedURLException ex) { Logger.getLogger(Urlconnection.class.getName()).log(Level.SEVERE, null, ex); } catch (IOException ex) { Logger.getLogger(Urlconnection.class.getName()).log(Level.SEVERE, null, ex); } } @Override public void start() { } @Override public void stop() { } @Override public void destroy() { } // TODO overwrite start(), stop() and destroy() methods } Here is the Rails controller function for recieving: def audiorecieve puts "///////////////////////////////////////******RECIEVED*******////" puts params[:key1]#+" "+params[:key2] data=params[:key1] #request.env('RAW_POST_DATA') file=File.new("audiodata.ogg", 'w') file.write(data) file.flush file.close puts "////**************DONE***********//////////////////////" end Please reply quickly

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• Samsung 830 very slow benchmark numbers

  - by alekop

  I just bought a new SSD, and installed a fresh copy of Windows on it. I didn't see any noticeable difference in boot times, app start-up times, so I decided to benchmark it. Asus P7P55D-E Intel i5-760 Samsung 830 256GB SATA III Windows 7 Ultimate 64-bit The Windows experience index gave the drive a 7.3 rating, but real-world performance is not particularly impressive. Any ideas why the numbers are so low? UPDATE: It turns out that SATA III support is turned off by default on the P7P55D motherboard. After enabling it in BIOS (Tools - Level Up), the scores went up: Read Write Seq 325 183 4K 16 49 IOPS 32K 28K It's an improvement, but still far below what they should be for this drive.

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• unable to get local issuer certificate - Ubuntu 11.04

  - by user1443867

  I'm facing a strange issue. My vps from Linode has no issue connecting to apple push server with following command. openssl s_client -connect gateway.sandbox.push.apple.com:2195 -cert Test_dev_apns_cert.pem -key Test_dev_apns_key.pem However, I was using the same pem files with above command testing from my another low budget vps and I'm getting this: Verify return code: 20 (unable to get local issuer certificate) Both are running Ubuntu 11.04 and installed LAMP as usual. No special configuration is done to both servers for SSL. Am I missing something here?

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• Can basic Geometry ever come useful to a Beginner to Intermediate skilled Java coder?

  - by Catfish

  Just Curious. I'm currently foraying into the world of Java coding, and, was wondering weather Geometry can come useful in the kind of programming a Beginner to Intermediate Skill level Java coder has.

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• Where does apache store initialization state for mod_proxy_balancer

  - by khoxsey

  I run apache2 on Ubuntu as a caching load-balancing reverse proxy in front of a group of application servers. I have noticed that the balancer maintains some state for some of the attributes visible in /balancer-manager such as whether an IP is enabled/disabled, load factor, etc. My site has periods of high (and low) usage, and recently as I added a new server to the working group I noticed that the load balancer picked up the new server but had it set to Disabled. I'm curious where that data is stored, and/or how it is initialized.

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• What's the point of Netgear's WNHDB3004 "3DHD WIRELESS HOME THEATER NETWORKING KIT"

  - by badp

  Here's a crude representation of what I've got at home: floor 2 INTERNETS ---- MODEM/ROUTER ---- MY COMPUTER | floor 1 WIFI REPEATER ---- stuff | floor 0 more stuff TELEVISION Now, as part of our sat tv subscription we can get an additional service if we connect our decoder (located by TELEVISION obviously) to the internet. What they suggest is buying a Netgear 3DHD WIRELESS HOME THEATER NETWORKING KIT holy shit isn't my bullshit-o-meter flying high right now from the general buzzwordyness of this thing. What does this thing actually do that our existing wireless-enabled routers don't do? What's the point of having a third wifi router in the same house, this time only for one television? If I do decide to plunge €99 for this, should I connect it to the wifi repeater (which does not provide AAA quality internet, at least for all gaming purposes) or to my modem/router (risking issues with low signal?).

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• Trouble recovering MySQL InnoDB database after server crash

  - by Andy Shinn

  I had a server crash due to a broken iSCSI link (the filesystem went into read-only mode). After repairing the link and rebooting the machine (CentOS 5 / MySQL 5.1), the MySQL server would not start and gave the following error: 100603 19:11:46 mysqld_safe Starting mysqld daemon with databases from /var/lib/mysql InnoDB: The log sequence number in ibdata files does not match InnoDB: the log sequence number in the ib_logfiles! 100603 19:11:46 InnoDB: Database was not shut down normally! InnoDB: Starting crash recovery. InnoDB: Reading tablespace information from the .ibd files... InnoDB: Restoring possible half-written data pages from the doublewrite InnoDB: buffer... InnoDB: Warning: database page corruption or a failed InnoDB: file read of page 112541. InnoDB: Trying to recover it from the doublewrite buffer. InnoDB: Dump of the page: 100603 19:11:46 InnoDB: Page dump in ascii and hex (16384 bytes): lots of binary data 100603 19:11:46 InnoDB: Page checksum 953720272, prior-to-4.0.14-form checksum 2641912043 InnoDB: stored checksum 617821918, prior-to-4.0.14-form stored checksum 2080617765 InnoDB: Page lsn 115 2632899642, low 4 bytes of lsn at page end 2641594600 InnoDB: Page number (if stored to page already) 112541, InnoDB: space id (if created with = MySQL-4.1.1 and stored already) 0 InnoDB: Page may be an index page where index id is 0 616 InnoDB: Dump of corresponding page in doublewrite buffer: 100603 19:11:46 InnoDB: Page dump in ascii and hex (16384 bytes): more binary data 100603 19:11:46 InnoDB: Page checksum 908374788, prior-to-4.0.14-form checksum 824841363 InnoDB: stored checksum 912869634, prior-to-4.0.14-form stored checksum 2210927931 InnoDB: Page lsn 115 2635312169, low 4 bytes of lsn at page end 2633173354 InnoDB: Page number (if stored to page already) 112541, InnoDB: space id (if created with = MySQL-4.1.1 and stored already) 0 InnoDB: Page may be an index page where index id is 0 616 InnoDB: Also the page in the doublewrite buffer is corrupt. InnoDB: Cannot continue operation. InnoDB: You can try to recover the database with the my.cnf InnoDB: option: InnoDB: innodb_force_recovery=6 100603 19:11:46 mysqld_safe mysqld from pid file /var/run/mysqld/mysqld.pid ended Per the error message, I have tried setting set-variable=innodb_force_recovery=6 in the my.cnf to get to the data. This allows the MySQL server to start. But when I try to do a mysqldump of the database or a SELECT * INTO OUTFILE "filename" FROM broken_table; it seems to endlessly just export the same line over and over again. I have also tried http://code.google.com/p/innodb-tools/. But this tool fails with an error that 'blob' type is not supported. If I try to access the data using the PHP application it crashes MySQL: `100603 19:19:19 - mysqld got signal 11 ; This could be because you hit a bug. It is also possible that this binary or one of the libraries it was linked against is corrupt, improperly built, or misconfigured. This error can also be caused by malfunctioning hardware. We will try our best to scrape up some info that will hopefully help diagnose the problem, but since we have already crashed, something is definitely wrong and this may fail. key_buffer_size=8384512 read_buffer_size=131072 max_used_connections=2 max_threads=151 threads_connected=2 It is possible that mysqld could use up to key_buffer_size + (read_buffer_size + sort_buffer_size)*max_threads = 338317 K bytes of memory Hope that's ok; if not, decrease some variables in the equation. thd: 0x15d33f0 Attempting backtrace. You can use the following information to find out where mysqld died. If you see no messages after this, something went terribly wrong... stack_bottom = 0x453aff00 thread_stack 0x40000 /usr/libexec/mysqld(my_print_stacktrace+0x24) [0x874364] /usr/libexec/mysqld(handle_segfault+0x346) [0x5c9166] /lib64/libpthread.so.0 [0x3a6e40eb10] /usr/libexec/mysqld(rec_get_offsets_func+0x30) [0x7cc310] /usr/libexec/mysqld [0x7674d8] /usr/libexec/mysqld(btr_search_info_update_slow+0x638) [0x768d48] /usr/libexec/mysqld(btr_cur_search_to_nth_level+0xc7d) [0x75f86d] /usr/libexec/mysqld [0x7dd1c1] /usr/libexec/mysqld(row_search_for_mysql+0x18b0) [0x7e03d0] /usr/libexec/mysqld(ha_innobase::general_fetch(unsigned char*, unsigned int, unsigned int)+0x7c) [0x7526fc] /usr/libexec/mysqld(handler::read_multi_range_next(st_key_multi_range**)+0x29) [0x6aed09] /usr/libexec/mysqld(QUICK_RANGE_SELECT::get_next()+0x194) [0x69a964] /usr/libexec/mysqld [0x6aafe9] /usr/libexec/mysqld(sub_select(JOIN*, st_join_table*, bool)+0x56) [0x635196] /usr/libexec/mysqld [0x63f9cd] /usr/libexec/mysqld(JOIN::exec()+0x950) [0x6497c0] /usr/libexec/mysqld(mysql_select(THD*, Item*, TABLE_LIST*, unsigned int, List&, Item*, unsigned int, st_order*, st_order*, Item*, st_order*, unsign ed long long, select_result*, st_select_lex_unit*, st_select_lex*)+0x17b) [0x64b34b] /usr/libexec/mysqld(handle_select(THD*, st_lex*, select_result*, unsigned long)+0x169) [0x64bc79] /usr/libexec/mysqld [0x5d34b6] /usr/libexec/mysqld(mysql_execute_command(THD*)+0x4e5) [0x5d6b45] /usr/libexec/mysqld(mysql_parse(THD*, char const*, unsigned int, char const)+0x211) [0x5dc321] /usr/libexec/mysqld(dispatch_command(enum_server_command, THD*, char*, unsigned int)+0x10b8) [0x5dd3f8] /usr/libexec/mysqld(do_command(THD*)+0xe6) [0x5dd9e6] /usr/libexec/mysqld(handle_one_connection+0x73d) [0x5d036d] /lib64/libpthread.so.0 [0x3a6e40673d] /lib64/libc.so.6(clone+0x6d) [0x3a6d4d3d1d] Trying to get some variables. Some pointers may be invalid and cause the dump to abort... thd-query at 0x15de5e0 = SELECT DISTINCT count(DISTINCT i.itemid) as rowscount,i.hostid FROM items i WHERE ((i.itemid BETWEEN 000000000000000 AND 0999999 99999999)) AND i.type<9 AND (i.hostid IN (10017,10047,10050,10054,10056,10059,10062,10063,10064,10065,10066,10067,10068,10069,10070,10071,10072,10073,100 74,10075,10076,10077,10078,10079,10080,10081,10082,10084,10088,10089,10090,10091,10092,10093,10094,10095,10096,10097,10098,10099,10100,10101,10102,10103,10 104,10105,10106,10107,10108,10109)) GROUP BY i.hostid thd-thread_id=3 thd-killed=NOT_KILLED The manual page at contains information that should help you find out what is causing the crash. 100603 19:19:19 mysqld_safe Number of processes running now: 0 100603 19:19:19 mysqld_safe mysqld restarted` Before recovering form an older backup as a last resort I am looking for anymore suggestions. Thanks!

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• Reconstructing data from PCAP sniff

  - by Ishi

  Hi everyone !! I am trying to sniff HTTP data through libpcap and get all the http contents (header+payload) after processing the TCP payload. As per my discussion at http://stackoverflow.com/questions/2905430/writing-an-http-sniffer-or-any-other-application-level-sniffer , I am facing problems due to fragmentation - I need to reconstruct the whole stream (or defragment it) to get a complete HTTP packet, and this is where I need some help. Thanks in anticipation !!

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• PostgreSQL custom exceptions?

  - by Steve F

  In Firebird we can declare custom exceptions like so: CREATE EXCEPTION EXP_CUSTOM_0 'Exception: Custom exception'; these are stored at the database level. In stored procedures, we can raise the exception like so: EXCEPTION EXP_CUSTOM_0 ; Is there an equivalent in PostgreSQL ?

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• Setting style of ContextMenu on subitems

  - by thedesertfox

  I have created a custom style and template for MenuItem and ContextMenu, and for my first level, that works great, but whenever I add a SubMenu item, the style of that ContextMenu reverts back to the default style. How can I make sure that item uses my custom style? I've tried using the <;Style TargetType="ContextMenu" Key="{x:Type ContextMenu}" syntax as well, and it doesn't seem to be overriding it either.

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• Epson XP-600 will not print properly with all new ink recently installed

  - by Joy

  I just installed brand new Epson 273 ink cartridges ($64 worth!) in my Epson XP-600 printer. One box had all the colors plus black, and one had the fatter black cartridge. I am not getting ANY black print on paper, although, when I lift the cartridges out, they show ink inside. Now the yellow is saying LOW though all cartridges are less than 2 weeks old. I only use this printer sparingly—not for business or work reasons. I am ready to scream, as the ink cost almost as much as the actual printer (which is barely 7 months old)! Any ideas on how to solve this issue?

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• Getting "GRUB loading ... no such partition"?

  - by shameedp

  I am having a dual os, windows 7 and linux, the c drive have 20 GB, in which 5 GB is allocated for windows 7 (original) and 15 gb for linux since the spacing for windows is very low i used EaseUS partition manager and deleted my linux OS, and merged the unused space into my C drive, now it becomes 20GB, the things, after the reboot, I am getting GRUB loading. Welcome to GRUB! error: no such partition. entering rescue mode. . . Kindly help me guys the problem i am facing is i dont have a DVD drive to resolve it, using recovery mode. Waiting for your reply guys. in ls command i have (hd0) (hd0,msdos8) (hd0,msdos7) (hd0,msdos6) (hd0,msdos5) (hd0,msdos2) (hd0,msdos1)

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• ATI radeon hd 5450 Graphics Card Issues

  - by RGM-79FP GM Striker

  I have an Old Dell Optiplex 755 SFF with an Intel Core 2 Processor (windows 7). Now This can hold a PCI-E x16 port. Now I got an ATI Radeon HD 5450 low profile. I plugged and played and it fits without a hitch, the software installed too! , now for the graphics well... It doesn't really work at all as it seems to freeze at the moment that it loads on the windows logo. It loads into safe mode so I'm not really sure what the problem is. Any ideas, I read the dell forums and they should be somewhat compatible... with the specs so I'm at a loss here. and I am a novice here. Ideas? Edit I have tried to reset the cmos,no luck there. I have tried to move the ram as well. nothing big happened.

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• How do I silence the following RightAWS messages when running tests

  - by Laurie Young

  I'm using the RighAWS gem, and mocking at the http level so that the RightAWS code is being executed as part of my tests. When this happens I get the following output ....New RightAws::S3Interface using per_request-connection mode Opening new HTTP connection to s3.amazonaws.com:80 .New RightAws::S3Interface using per_request-connection mode . Even though all the tests pass, when I do have errors its harder to scan them because of this output. is there a nice way to silence it?

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• Silverlight IDE for latest version (May 2010)

  - by lexu

  In 2008 Artur Carvalho asked for an Alternative IDE for Silverlight and was told to look at Visual Studio Express. Is that still the valid answer in 2010 or are there other IDEs one should consider (cost/ OS it runs on / stability)? I'm trying to get a feel for silverlight development before commiting cash. So I don't need enterprize level tools or a license to distribute .. Would MonoDevelop and Moonlight be an option?

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• Tips on self-learning boot-time fundamentals (grub, disks, partitions, LVMs, etc)?

  - by Harry

  Is there any good resource which I can use to self-learn all the low-level system administration details on Grub, Grub2, disks, partitioning, LVM, etc? I'm comfortable with system admin tasks post-boot but I lack knowledge about both the fundamentals and actuals of all that happens during boot on a Linux system such as Fedora. Any recommendations on how to setup a testbed on my desktop for learning the above? I may not be able to get another machine / harddisk, so may have to rely on something like VirtualBox. But don't know if there are other (better) options... so asking for tips from those who have self-learned / mastered this track themselves.

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• Internal USB A Female to motherboard 4-pin that mounts internally

  - by rockinthesixstring

  I'm wondering if anyone knows of a product like this but that is physically mountable internally rather than on a cable? I'm planning on building a super low profile "gateway" pc that is dedicated to handling internet traffic in my home. I have a great 1U rackmountable chassis for an ITX motherboard, but I need the hard drive real estate for the additional NIC required to run a gateway (one onboard and one PCI). So the plan is to use a small 8GB USB Jump Drive for the OS inside the box (as to not have one hanging out the back. And although it's racked, I still don't want the jump drive flopping around internally, so I want it fixed somehow. I have an alternative idea where by I use a flush mount zap strap saddle and a zip tie to hold it in place, but that seems kind of like a hack.

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• Sharp flat panel scaling with Nvidia drivers

  - by Brecht Machiels

  I have a Samsung 226BW flat panel with a 1680x1050 native resolution. As my PC is rather dated (Athlon XP 2600+ and GeForce 6600 GT), I need to run more recent games (but still old) on a lower resolution. Unfortunately, scaling low resolutions to 1680x1050 results in a very blurry image (bilinear scaling). I have created a custom resolution of 840x525 in the Nvidia control panel. Technically, this resolutions allows perfect upscaling to 1680x1050 without the need for bilinear interpolation. Unfortunately, the Nvidia driver always seems to do bilinear scaling, again resulting in a blurry image. However, I seem to remember that I did obtain crisp images using this resolution in the past (before a Windows re-install). Maybe only some driver versions support integer upscaling without bilinear filtering? Or perhaps there are other solutions?

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• CPU Cooling with Heatsinks

  - by Jason Tzen

  I've constructed a server that uses 2 Xeon E5-2620 CPUs and per Intel's recommendation I'm in the process of ordering heatsinks for each and I'm slightly concerned about thermal management. The case I'm using is well ventilated (the Coolermaster Cosmos II) but I have a few concerns regarding the adequacy of the heatsinks recommended by the MB manufacturer (Supermicro CPU HeatSink SNK-P0048PS). As you can see these heatsinks come without a fan and I'm wondering if they can keep the Xeons within their normal temperature range... Due to the low volume of literature on the topic I wasn't able to find anything conclusive.

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• Source Code Linux built in Services

  - by Sirish Kumar

  Hi, I am looking at linux startup services, like Cron which runs at level 5 located in init.d, in the startup script I can only see the script file and location of binary file which is executed on startup. Where can I see the actual source code of this services

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• Is there any way to find unreferenced code in Flex Builder?

  - by Andrew Aylett

  We've got several Flex projects, one of which has just been refactored. I'm wondering if there's an easy way to tell which classes and functions (if any) aren't being used any more? I've discovered that we've definitely got some unused code, because running ASDoc on the entire project reports some compilation errors which don't get reported by Flex Builder (implying that those classes aren't being used any more). I'm hoping to find a more robust and complete method, and preferably one which can work at function level too.

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• Managing highly repetitive code and documentation in Java

  - by polygenelubricants

  Highly repetitive code is generally a bad thing, and there are design patterns that can help minimize this. However, sometimes it's simply inevitable due to the constraints of the language itself. Take the following example from java.util.Arrays: /** * Assigns the specified long value to each element of the specified * range of the specified array of longs. The range to be filled * extends from index <tt>fromIndex</tt>, inclusive, to index * <tt>toIndex</tt>, exclusive. (If <tt>fromIndex==toIndex</tt>, the * range to be filled is empty.) * * @param a the array to be filled * @param fromIndex the index of the first element (inclusive) to be * filled with the specified value * @param toIndex the index of the last element (exclusive) to be * filled with the specified value * @param val the value to be stored in all elements of the array * @throws IllegalArgumentException if <tt>fromIndex &gt; toIndex</tt> * @throws ArrayIndexOutOfBoundsException if <tt>fromIndex &lt; 0</tt> or * <tt>toIndex &gt; a.length</tt> */ public static void fill(long[] a, int fromIndex, int toIndex, long val) { rangeCheck(a.length, fromIndex, toIndex); for (int i=fromIndex; i<toIndex; i++) a[i] = val; } The above snippet appears in the source code 8 times, with very little variation in the documentation/method signature but exactly the same method body, one for each of the root array types int[], short[], char[], byte[], boolean[], double[], float[], and Object[]. I believe that unless one resorts to reflection (which is an entirely different subject in itself), this repetition is inevitable. I understand that as a utility class, such high concentration of repetitive Java code is highly atypical, but even with the best practice, repetition does happen! Refactoring doesn't always work because it's not always possible (the obvious case is when the repetition is in the documentation). Obviously maintaining this source code is a nightmare. A slight typo in the documentation, or a minor bug in the implementation, is multiplied by however many repetitions was made. In fact, the best example happens to involve this exact class: Google Research Blog - Extra, Extra - Read All About It: Nearly All Binary Searches and Mergesorts are Broken (by Joshua Bloch, Software Engineer) The bug is a surprisingly subtle one, occurring in what many thought to be just a simple and straightforward algorithm. // int mid =(low + high) / 2; // the bug int mid = (low + high) >>> 1; // the fix The above line appears 11 times in the source code! So my questions are: How are these kinds of repetitive Java code/documentation handled in practice? How are they developed, maintained, and tested? Do you start with "the original", and make it as mature as possible, and then copy and paste as necessary and hope you didn't make a mistake? And if you did make a mistake in the original, then just fix it everywhere, unless you're comfortable with deleting the copies and repeating the whole replication process? And you apply this same process for the testing code as well? Would Java benefit from some sort of limited-use source code preprocessing for this kind of thing? Perhaps Sun has their own preprocessor to help write, maintain, document and test these kind of repetitive library code? A comment requested another example, so I pulled this one from Google Collections: com.google.common.base.Predicates lines 276-310 (AndPredicate) vs lines 312-346 (OrPredicate). The source for these two classes are identical, except for: AndPredicate vs OrPredicate (each appears 5 times in its class) "And(" vs Or(" (in the respective toString() methods) #and vs #or (in the @see Javadoc comments) true vs false (in apply; ! can be rewritten out of the expression) -1 /* all bits on */ vs 0 /* all bits off */ in hashCode() &= vs |= in hashCode()

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• Axis2 aar file structure question

  - by Alan Mangroo

  I trying to create an Axis2 arr file that has 2 package heirachies. However my service class is throwing a class not found exception when it tries to use classes in the utils package. Is it possible to do this in Axis? Any advice is very welcome. Below is an example of the structure I am trying to create (utils and org are both top level packages)... |- SampleService |-- META-INF |--- services.xml |-- utils |---MyUtils.class |-- org |---- apache |---- axis2 |----- axis2userguide |------ SampleService.class

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