Search Results

Search found 3659 results on 147 pages for 'sorted hash'.

Page 82/147 | < Previous Page | 78 79 80 81 82 83 84 85 86 87 88 89  | Next Page >

  • Flushing JDBC connection pools

    - by Matt
    Does anyone know the best (or any) way to flush a JDBC connection pool? I can't find anything obvious in the documentation. It appears connection pools aren't meant to ever be deleted. My current thought is to delete all DataSources from the hash we store them in, which will trigger our code to make new ones. However, my first attempt throws a ConcurrentModificationException.

    Read the article

  • Why is Dictionary.First() so slow?

    - by Rotsor
    Not a real question because I already found out the answer, but still interesting thing. I always thought that hash table is the fastest associative container if you hash properly. However, the following code is terribly slow. It executes only about 1 million iterations and takes more than 2 minutes of time on a Core 2 CPU. The code does the following: it maintains the collection todo of items it needs to process. At each iteration it takes an item from this collection (doesn't matter which item), deletes it, processes it if it wasn't processed (possibly adding more items to process), and repeats this until there are no items to process. The culprit seems to be the Dictionary.Keys.First() operation. The question is why is it slow? Stopwatch watch = new Stopwatch(); watch.Start(); HashSet<int> processed = new HashSet<int>(); Dictionary<int, int> todo = new Dictionary<int, int>(); todo.Add(1, 1); int iterations = 0; int limit = 500000; while (todo.Count > 0) { iterations++; var key = todo.Keys.First(); var value = todo[key]; todo.Remove(key); if (!processed.Contains(key)) { processed.Add(key); // process item here if (key < limit) { todo[key + 13] = value + 1; todo[key + 7] = value + 1; } // doesn't matter much how } } Console.WriteLine("Iterations: {0}; Time: {1}.", iterations, watch.Elapsed); This results in: Iterations: 923007; Time: 00:02:09.8414388. Simply changing Dictionary to SortedDictionary yields: Iterations: 499976; Time: 00:00:00.4451514. 300 times faster while having only 2 times less iterations. The same happens in java. Used HashMap instead of Dictionary and keySet().iterator().next() instead of Keys.First().

    Read the article

  • VIM Blockwise Insert

    - by tesmar
    HI all! I would like to insert a hash at the beginning of a selected block of text in VIM (ruby comment). I selected the lines in Visual Mode, but how do I perform the same operation to all lines? Thank you in advance!

    Read the article

  • Am I supposed to store hashes for passwords?

    - by Doug
    User System and Passwords: I was looking through MD5 stuff, and I am wondering what is the normal/good practice for passwords. Right now, I think people super encrypt the passwords and store the hashes. If so, how does password checking work? I just have the input password go through the encryption process again and then check the hash with the stored one, correct? This question may contradict the above, but should my salt ever be a randomly generated value?

    Read the article

  • Can I use a filehandle instead of a filename for creating DBM files?

    - by Dancrumb
    I'm using MLDBM to persist some Perl data structures and I'm wondering if there's an alternative to the following: tie %hash, "MLDBM", $dbm_file, O_CREAT | O_RDWR, 0644; Primarily, I'd like to be able to use STDOUT, rather than a known file name. This could then be redirected to a file on the shell-side. I've been searching with keywords like "tie", "DBM" and "filehandle", but the hits tend to talk about tying filehandles to things, as opposed to things to filehandles. Any suggestions?

    Read the article

  • Split a string by two characters

    - by David
    Hi, Firstable i want to match if a string has the following format: $abc #xyz or $abc .xyz. The abc and xyz mean only alphanumeric string. If it's matched then i need to extract the first $abc and the last #xyz, all that using pure javascript and maybe regex. The pattern is in the following order: Dollar Sign Unlimited alphanumeric string space a hash or point Unlimited alphanumeric string Thanks in advance for any help.

    Read the article

  • Adding a LIKE criteria to a Rails Conditions block

    - by Neil Middleton
    Consider the following code which is to be thrown at an AR find: conditions = [] conditions[:age] = params[:age] if params[:age].present? conditions[:gender] = params[:gender] if params[:gender].present? I need to add another condition which is a LIKE criteria on a 'profile' attribute. How can I do this, as obviously a LIKE is usually done via an array, not a hash key.

    Read the article

  • What's the purpose of the rotate instructions (ROL, RCL on x86) ?

    - by lgratian
    I always wondered what's the purpose of the rotate instructions some CPUs have (ROL, RCL on x86, for example). What kind of software makes use of these instructions? I first thought they may be used for encryption/computing hash codes, but these libraries are written usually in C, which doesn't have operators that map to these instructions. Has anybody found an use for them? Why where they added to the instructions set?

    Read the article

  • What's the best way to handle modules that use each other?

    - by Axeman
    What's the best way to handle modules that use each other? Let's say I have a module which has functions for hashes: # Really::Useful::Functions::On::Hash.pm use base qw<Exporter>; use strict; use warnings; use Really::Useful::Functions::On::List qw<transform_list>; our @EXPORT_OK = qw<transform_hash transform_hash_as_list ...>; #... sub transform_hash { ... } #... sub transform_hash_as_list { return transform_list( %{ shift() } ); } #... 1 And another module has been segmented out for lists: # Really::Useful::Functions::On::List.pm use base qw<Exporter>; use strict; use warnings; use Really::Useful::Functions::On::Hash qw<transform_hash>; our @EXPORT_OK = qw<transform_list some_func ...>; #... sub transform_list { ... } #... sub some_func { my %params = transform_hash @_; #... } #... 1 Suppose that enough of these utility functions are handy enough that I'll want to use them in BEGIN statements and import functions to process parameter lists or configuration data. I have been putting sub definitions into BEGIN blocks to make sure they are ready to use whenever somebody includes the module. But I have gotten into hairy race conditions where a definition is not completed in a BEGIN block. I put evolving code idioms into modules so that I can reuse any idiom I find myself coding over and over again. For instance: sub list_if { my $condition = shift; return unless $condition; my $more_args = scalar @_; my $arg_list = @_ > 1 ? \@_ : @_ ? shift : $condition; if (( reftype( $arg_list ) || '' ) eq 'ARRAY' ) { return wantarray ? @$arg_list : $arg_list; } elsif ( $more_args ) { return $arg_list; } return; } captures two idioms that I'm kind of tired of typing: @{ func_I_hope_returns_a_listref() || [] } and ( $condition ? LIST : ()) The more I define functions in BEGIN blocks, the more likely I'll use these idiom bricks to express the logic the more likely that bricks are needed in BEGIN blocks. Do people have standard ways of dealing with this sort of language-idiom-brick model? I've been doing mostly Pure-Perl; will XS alleviate some of this?

    Read the article

  • Passing data between blocks using sinatra

    - by Dan Galipo
    Hi All I'm trying to pass data between blocks using sinatra. For example: @data = Hash.new post "/" do @data[:test] = params.fetch("test").to_s redirect "/tmp" end get "/tmp" do puts @data[:test] end However whenever i get to the tmp block @data is nil and throws an error. Why is that?

    Read the article

  • How do Perl FIRSTKEY and NEXTKEY work

    - by mmccoo
    Tie::Hash has these: sub FIRSTKEY { my $a = scalar keys %{$_[0]}; each %{$_[0]} } sub NEXTKEY { each %{$_[0]} } NEXTKEY takes two arguments, one of which is the last key but that arg is never referenced? The various Tie docs don't shed any light on this other than this in perltie: my $a = keys %{$self->{LIST}}; # reset each() iterator looking at the doc for each doesn't add to this. What's going on?

    Read the article

  • How to make a copy of a char and not a reference in C++

    - by Phenom
    If I declare a function like this: string hash (char* key) then any change I make to key will also change it's value when the function exits, correct? I want to make a copy of it in the function so that I can safely change it without changing the original value. I tried this, but it doesn't work. string temp = key; How can it be done?

    Read the article

  • is this aes encryption wrapper safe ? - yet another take...

    - by user393087
    After taking into accound answers for my questions here and here I created (well may-be) improved version of my wrapper. The key issue was what if an attacker is knowing what is encoded - he might then find the key and encode another messages. So I added XOR before encryption. I also in this version prepend IV to the data as was suggested. sha256 on key is only for making sure the key is as long as needed for the aes alg, but I know that key should not be plain text but calculated with many iterations to prevent dictionary attack function aes192ctr_en($data,$key) { $iv = mcrypt_create_iv(24,MCRYPT_DEV_URANDOM); $xor = mcrypt_create_iv(24,MCRYPT_DEV_URANDOM); $key = hash_hmac('sha256',$key,$iv,true); $data = $xor.((string)$data ^ (string)str_repeat($xor,(strlen($data)/24)+1)); $data = hash('md5',$data,true).$data; return $iv.mcrypt_encrypt('rijndael-192',$key,$data,'ctr',$iv); } function aes192ctr_de($data,$key) { $iv = substr($data,0,24); $data = substr($data,24); $key = hash_hmac('sha256',$key,$iv,true); $data = mcrypt_decrypt('rijndael-192',$key,$data,'ctr',$iv); $md5 = substr($data,0,16); $data = substr($data,16); if (hash('md5',$data,true)!==$md5) return false; $xor = substr($data,0,24); $data = substr($data,24); $data = ((string)$data ^ (string)str_repeat($xor,(strlen($data)/24)+1)); return $data; } $encrypted = aes192ctr_en('secret text','password'); echo $encrypted; echo aes192ctr_de($encrypted,'password'); another question is if ctr mode is ok in this context, would it be better if I use cbc mode ? Again, by safe I mean if an attacter could guess password if he knows exact text that was encrypted and knows above method. I assume random and long password here. Maybe instead of XOR will be safer to random initial data with another run of aes or other simpler alg like TEA or trivium ?

    Read the article

  • click handler after using Ajax

    - by Tom
    I have a site that plays a stream. I perform an AJAX call to the server once a person presses a button. <input type="submit" class="play" data-type="<?php echo $result_cameras[$i]["camera_type"]; ?>" data-hash="<?php echo $result_cameras[$i]["camera_hash"]; ?>" value="<?php echo $result_cameras[$i]["camera_name"]; ?>"> This prints out a bunch of buttons that the user can select. This is processed by the following code: <script> $(document).ready(function(){ $(".play").click(function(){ var camerahash = $(this).data('hash'); var cameratype = $(this).data('type'); function doAjax(){ $.ajax({ url: 'index.php?option=streaming&task=playstream&id_hash=<?php echo $id_hash; ?>&camera_hash='+camerahash+'&format=raw', success: function(data) { if (data == 'Initializing...please wait') { $('#quote p').html(data); setTimeout(doAjax, 2000); } else { if (cameratype == "WEBCAM" && data == 'Stream is ready...') { $('#quote p').html(data); window.location = 'rtsp://<?php echo DEVSTREAMWEB; ?>/<?php echo $session_id;?>/'+camerahash; } else if (cameratype == "AXIS" && data == 'Stream is ready...') { $('#quote p').html(data); window.location = 'rtsp://<?php echo DEVSTREAMIP; ?>/<?php echo $session_id;?>/'+camerahash; } else { $('#quote p').html(data); } } } }); } doAjax(); }); }); </script> The server returns the messages such as Stream is ready.... My problem is that everything is working great except on additional button clicks. Specifically when they get success (video plays) and they exit back out, they don't get any other messages if they click another button. It is as if the click event is not triggered. Do I need to be doing something to the click handler to respond?

    Read the article

  • PHP: A way for a file to have its own MD5 inside?

    - by Eli
    Hi all, In considering several possible solutions to a recent task, I found myself considering how to get a php file that includes it's own MD5 hash. I ended up doing something else, but the question stayed with me. Something along the lines of: <?php echo("Hello, my MD5 is [MD5 OF THIS FILE HERE]"); ?> Whatever placeholder you have in the file, the second you take its MD5 and insert it, you've changed it.

    Read the article

  • object reference set in java

    - by landon9720
    I need to create a Set of objects. The concern is I do not want to base the hashing or the equality on the objects' hashCode and equals implementation. Instead, I want the hash code and equality to be based only on each object's reference identity (i.e.: the value of the reference pointer). I'm not sure how to do this in Java. The reasoning behind this is my objects do not reliably implement equals or hashCode, and in this case reference identity is good enough.

    Read the article

< Previous Page | 78 79 80 81 82 83 84 85 86 87 88 89  | Next Page >