Search Results

Search found 13415 results on 537 pages for 'variable caching'.

Page 191/537 | < Previous Page | 187 188 189 190 191 192 193 194 195 196 197 198  | Next Page >

  • Are specific types still necessary?

    - by MKO
    One thing that occurred to me the other day, are specific types still necessary or a legacy that is holding us back. What I mean is: do we really need short, int, long, bigint etc etc. I understand the reasoning, variables/objects are kept in memory, memory needs to be allocated and therefore we need to know how big a variable can be. But really, shouldn't a modern programming language be able to handle "adaptive types", ie, if something is only ever allocated in the shortint range it uses fewer bytes, and if something is suddenly allocated a very big number the memory is allocated accordinly for that particular instance. Float, real and double's are a bit trickier since the type depends on what precision you need. Strings should however be able to take upp less memory in many instances (in .Net) where mostly ascii is used buth strings always take up double the memory because of unicode encoding. One argument for specific types might be that it's part of the specification, ie for example a variable should not be able to be bigger than a certain value so we set it to shortint. But why not have type constraints instead? It would be much more flexible and powerful to be able to set permissible ranges and values on variables (and properties). I realize the immense problem in revamping the type architecture since it's so tightly integrated with underlying hardware and things like serialization might become tricky indeed. But from a programming perspective it should be great no?

    Read the article

  • Reasons behind polymorphism related behaviour in java

    - by Shades88
    I read this code somewhere class Foo { public int a; public Foo() { a = 3; } public void addFive() { a += 5; } public int getA() { System.out.println("we are here in base class!"); return a; } } public class Polymorphism extends Foo{ public int a; public Poylmorphism() { a = 5; } public void addFive() { System.out.println("we are here !" + a); a += 5; } public int getA() { System.out.println("we are here in sub class!"); return a; } public static void main(String [] main) { Foo f = new Polymorphism(); f.addFive(); System.out.println(f.getA()); // SOP 1 System.out.println(f.a); // SOP 2 } } For SOP1 we get answer 10 and for SOP2 we get answer 3. Reason for this is that you can't override variables whereas you can do so for methods. This happens because type of the reference variable is checked when a variable is accessed and type of the object is checked when a method is accessed. But I am wondering, just why is it that way? Can anyone explain me what is the reason for this behaviour

    Read the article

  • What language available on commodity web hosts would suit a C# developer? [closed]

    - by billpg
    Recognising its ubiquity on commodity web hosting services, I tried developing in PHP a few years ago. I really didn't like it, later deciding that life was too short for PHP. (In brief, having to put $ on variable names; mis-spelt variable names become new variables; converting non-numeric strings to integers without complaint; the need for an "and this time I mean it" comparison operator.) In my ideal world, commodity web hosts would all support C#/ASP.NET, my preferred web-development language and framework, but this is not my ideal world. Even Mono has barely made a dent on Linux based hosts. However, last time I moaned about PHP's ubiquity, someone followed up that this was no longer the case, and that many other languages are now commonly usable on web hosts too. What programming language; a. Would suit a developer who prefers C#. b. Is available to run on many web hosts.

    Read the article

  • Do ALL your variables need to be declared private? [closed]

    - by skizeey
    Possible Duplicate: Why do we need private variables? I know that it's best practice to stay safe, and that we should always prevent others from directly accessing a class' properties. I hear this all the time from university professors, and I also see this all the time in a lot of source code released on the App Hub. In fact, professors say that they will actually take marks off for every variable that gets declared public. Now, this leaves me always declaring variables as private. No matter what. Even if each of these variables were to have both a getter and a setter. But here's the problem: it's tedious work. I tend to quickly lose interest in a project every time I need to have a variable in a class that could have simply been declared public instead of private with a getter and a setter. So my question is, do I really need to declare all my variables private? Or could I declare some variables public whenever they require both a getter and a setter?

    Read the article

  • How can I malloc an array of struct to do the following using file operation?

    - by RHN
    How can malloc an array of struct to do the following using file operation? the file is .txt input in the file is like: 10 22 3.3 33 4.4 I want to read the first line from the file and then I want to malloc an array of input structures equal to the number of lines to be read in from the file. Then I want to read in the data from the file and into the array of structures malloc. Later on I want to store the size of the array into the input variable size. return an array.After this I want to create another function that print out the data in the input variable in the same form like input file and suppose a function call clean_data will free the malloc memory at the end. I have tried somthing like: struct input { int a; float b,c; } struct input* readData(char *filename,int *size); int main() { return 0; } struct input* readData(char *filename,int *size) { char filename[] = "input.txt"; FILE *fp = fopen(filename, "r"); int num; while(!feof(fp)) { fscanf(fp,"%f", &num); struct input *arr = (struct input*)malloc(sizeof(struct input)); } }

    Read the article

  • Is there an alternative to the term "calling object"?

    - by ybakos
    Let's suppose you've got a class defined (in pseudocode): class Puppy { // ... string sound = "Rawr!"; void bark() { print(sound); } } And say, given a Puppy instance, you call it's bark() method: Puppy p; p.bark(); Notice how bark() uses the member variable sound. In many contexts, I've seen folks describe sound as the member variable of the "calling object." My question is, what's a better term to use than "calling object?" To me, the object is not doing any calling. We know that member functions are in a way just functions with an implicit this or self parameter. I've come up with "receiving object," or "message recipient," which makes sense if you're down with the "messaging" paradigm. Do any of you happy hackers have a term that you like to use? I feel it should mean "the object upon which a method is called" and TOUWAMIC just doesn't cut it.

    Read the article

  • Problems moving a rectangle in Pygame.

    - by Yann Core
    Hi guys! I'm making a game in Pygame and I want to be able to target enemy unit. I made it so when I click on them a variable "targeted" becomes true, and stays true until I click somewhere else on the screen. I also want targeted units to have a small green circle around them, so I made it in GEDIT. I have made a function that draws everything on the screen (the background, the player, objects, etc) and in the part where it draws the units it checks if the variable "targeted" is true and if it is it should move that little green circle over the enemy units. here is the code that does that: screen.blit(enemy_unit.pic, enemy_unit.rect) #draw the unit if enemy_unit.targeted == True: #if the unit has been targeted then draw a circle over it target_rect.move_ip(enemy_unit.pos) #move the circle to the unit target_rect.fit(enemy_unit.rect) #there are some bigger units and some smaller ones, so we have to "scale" the circle screen.blit(target_pic, target_rect) #actually draw the circle This doesn't work, when I target the unit the circle just appears for a 1/5 of second next (not on, but just next) to the unit and then disappears. I am sure that I am keeping a good track of "enemy_unit.pos" because I tested it (I added a piece of code that would print one units position and mouse's position every time i clicked the mouse and when i was near him the numbers were same). If you could give me a hint about what I'm doing wrong. I think its in move_ip function, but I tried just move and it didn't work either (the circle didn't even show at all)!

    Read the article

  • batch: comparing filenames and renaming [migrated]

    - by user2978770
    i'm new to both this platform and batch programming and i'm slowly but steadily driving crazy :-( I'm studying in Germany and just started on a bigger project that mainly consists of analyzing data and finding algorithms in order to maintain a certain function of a system. In order to get started i got a bunch of recorded data that, unfortunately, is not consistent when i comes to naming. Normally all files (all in one folder) should start with SPY.SPYNODE.SIDE and then go on with the specific names for each values or variables. However, the data logger messed it up a couple of times and gives weird names like SP0E1A~1.csv (all files are .csv-files). An that's when i figured in stead of renaming a couple of thousand files manually i could "easily" use a simple batch file to do that job for name. And that's exactly when I started to go crazy :-) So far i came up with the following: FOR /R %%i in (%CD%) DO ( set file1=%%i if not %file1%=="SPY.SPYNODE.SIDE" DO ( set /p "filename" < %file1% rename %file1% %filename% ) ) So what i want it to do is this (in pseudo) look through the whole folder and every file save the filename in variable file1 if file1 partially equals SPY.SPYNODE.SIDE open the file and save the first line (which contains the correct name of the file) in variable filename rename the file with the correct filename But so far it doesn't really work and i don't know why. Could anybody give me a hint or some advice how i should proceed? I really appreciate any kind of help!

    Read the article

  • just can't get a controller to work

    - by Asaf
    I try to get into mysite/user so that application/classes/controller/user.php should be working, now this is my file tree: code of controller/user.php: <?php defined('SYSPATH') OR die('No direct access allowed.'); class Controller_User extends Controller_Default { public $template = 'user'; function action_index() { //$view = View::factory('user'); //$view->render(TRUE); $this->template->message = 'hello, world!'; } } ?> code of controller/default.php: <?php defined('SYSPATH') OR die('No direct access allowed.'); class Controller_default extends Controller_Template { } bootstrap.php: <?php defined('SYSPATH') or die('No direct script access.'); //-- Environment setup -------------------------------------------------------- /** * Set the default time zone. * * @see http://kohanaframework.org/guide/using.configuration * @see http://php.net/timezones */ date_default_timezone_set('America/Chicago'); /** * Set the default locale. * * @see http://kohanaframework.org/guide/using.configuration * @see http://php.net/setlocale */ setlocale(LC_ALL, 'en_US.utf-8'); /** * Enable the Kohana auto-loader. * * @see http://kohanaframework.org/guide/using.autoloading * @see http://php.net/spl_autoload_register */ spl_autoload_register(array('Kohana', 'auto_load')); /** * Enable the Kohana auto-loader for unserialization. * * @see http://php.net/spl_autoload_call * @see http://php.net/manual/var.configuration.php#unserialize-callback-func */ ini_set('unserialize_callback_func', 'spl_autoload_call'); //-- Configuration and initialization ----------------------------------------- /** * Initialize Kohana, setting the default options. * * The following options are available: * * - string base_url path, and optionally domain, of your application NULL * - string index_file name of your index file, usually "index.php" index.php * - string charset internal character set used for input and output utf-8 * - string cache_dir set the internal cache directory APPPATH/cache * - boolean errors enable or disable error handling TRUE * - boolean profile enable or disable internal profiling TRUE * - boolean caching enable or disable internal caching FALSE */ Kohana::init(array( 'base_url' => '/mysite/', 'index_file' => FALSE, )); /** * Attach the file write to logging. Multiple writers are supported. */ Kohana::$log->attach(new Kohana_Log_File(APPPATH.'logs')); /** * Attach a file reader to config. Multiple readers are supported. */ Kohana::$config->attach(new Kohana_Config_File); /** * Enable modules. Modules are referenced by a relative or absolute path. */ Kohana::modules(array( 'auth' => MODPATH.'auth', // Basic authentication 'cache' => MODPATH.'cache', // Caching with multiple backends 'codebench' => MODPATH.'codebench', // Benchmarking tool 'database' => MODPATH.'database', // Database access 'image' => MODPATH.'image', // Image manipulation 'orm' => MODPATH.'orm', // Object Relationship Mapping 'pagination' => MODPATH.'pagination', // Paging of results 'userguide' => MODPATH.'userguide', // User guide and API documentation )); /** * Set the routes. Each route must have a minimum of a name, a URI and a set of * defaults for the URI. */ Route::set('default', '(<controller>(/<action>(/<id>)))') ->defaults(array( 'controller' => 'welcome', 'action' => 'index', )); /** * Execute the main request. A source of the URI can be passed, eg: $_SERVER['PATH_INFO']. * If no source is specified, the URI will be automatically detected. */ echo Request::instance() ->execute() ->send_headers() ->response; ?> .htaccess: RewriteEngine On RewriteBase /mysite/ RewriteRule ^(application|modules|system) - [F,L] RewriteCond %{REQUEST_FILENAME} !-f RewriteCond %{REQUEST_FILENAME} !-d RewriteRule .* index.php/$0 [PT,L] Trying to go to http://localhost/ makes the "hello world" page, from the welcome.php Trying to go to http://localhost/mysite/user give me this: The requested URL /mysite/user was not found on this server.

    Read the article

  • XSL-FO: Force Wrap on Table Entries

    - by Ace
    I'm having an issue where when I publish my modspecs to pdf (XSL-FO). My tables are having issues, where the content of a cell will overflow its column into the next one. How do I force a break on the text so that a new line is created instead? I can't manually insert zero-space characters since the table entries are programmatically entered. I'm looking for a simple solution that I can just simply add to docbook_pdf.xsl (either as a xsl:param or xsl:attribute) EDIT: Here is where I'm at currently: <xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="2.0" xmlns:fo="http://www.w3.org/1999/XSL/Format"> <xsl:import href="urn:docbkx:stylesheet"/> ...(the beginning of my stylesheet for pdf generation, e.g. header and footer content stuff) <xsl:template match="text()"> <xsl:call-template name="intersperse-with-zero-spaces"> <xsl:with-param name="str" select="."/> </xsl:call-template> </xsl:template> <xsl:template name="intersperse-with-zero-spaces"> <xsl:param name="str"/> <xsl:variable name="spacechars"> &#x9;&#xA; &#x2000;&#x2001;&#x2002;&#x2003;&#x2004;&#x2005; &#x2006;&#x2007;&#x2008;&#x2009;&#x200A;&#x200B; </xsl:variable> <xsl:if test="string-length($str) &gt; 0"> <xsl:variable name="c1" select="substring($str, 1, 1)"/> <xsl:variable name="c2" select="substring($str, 2, 1)"/> <xsl:value-of select="$c1"/> <xsl:if test="$c2 != '' and not(contains($spacechars, $c1) or contains($spacechars, $c2))"> <xsl:text>&#x200B;</xsl:text> </xsl:if> <xsl:call-template name="intersperse-with-zero-spaces"> <xsl:with-param name="str" select="substring($str, 2)"/> </xsl:call-template> </xsl:if> </xsl:template> </xsl:stylesheet> With this, the long words are successfully broken up in the table cells! Unfortunately, the side effect is that normal text elsewhere (like in a under sextion X) now breaks up words so that they appear on seperate lines. Is there a way to isolate the above process to just tables? EDIT #2 here is what the fo spits out for a single table... <fo:table-row><fo:table-cell padding-start="2pt" padding-end="2pt" padding-top="2pt" ... </fo:block></fo:table-cell></fo:table-row>

    Read the article

  • Optimal storage of data structure for fast lookup and persistence

    - by Mikael Svenson
    Scenario I have the following methods: public void AddItemSecurity(int itemId, int[] userIds) public int[] GetValidItemIds(int userId) Initially I'm thinking storage on the form: itemId -> userId, userId, userId and userId -> itemId, itemId, itemId AddItemSecurity is based on how I get data from a third party API, GetValidItemIds is how I want to use it at runtime. There are potentially 2000 users and 10 million items. Item id's are on the form: 2007123456, 2010001234 (10 digits where first four represent the year). AddItemSecurity does not have to perform super fast, but GetValidIds needs to be subsecond. Also, if there is an update on an existing itemId I need to remove that itemId for users no longer in the list. I'm trying to think about how I should store this in an optimal fashion. Preferably on disk (with caching), but I want the code maintainable and clean. If the item id's had started at 0, I thought about creating a byte array the length of MaxItemId / 8 for each user, and set a true/false bit if the item was present or not. That would limit the array length to little over 1mb per user and give fast lookups as well as an easy way to update the list per user. By persisting this as Memory Mapped Files with the .Net 4 framework I think I would get decent caching as well (if the machine has enough RAM) without implementing caching logic myself. Parsing the id, stripping out the year, and store an array per year could be a solution. The ItemId - UserId[] list can be serialized directly to disk and read/write with a normal FileStream in order to persist the list and diff it when there are changes. Each time a new user is added all the lists have to updated as well, but this can be done nightly. Question Should I continue to try out this approach, or are there other paths which should be explored as well? I'm thinking SQL server will not perform fast enough, and it would give an overhead (at least if it's hosted on a different server), but my assumptions might be wrong. Any thought or insights on the matter is appreciated. And I want to try to solve it without adding too much hardware :) [Update 2010-03-31] I have now tested with SQL server 2008 under the following conditions. Table with two columns (userid,itemid) both are Int Clustered index on the two columns Added ~800.000 items for 180 users - Total of 144 million rows Allocated 4gb ram for SQL server Dual Core 2.66ghz laptop SSD disk Use a SqlDataReader to read all itemid's into a List Loop over all users If I run one thread it averages on 0.2 seconds. When I add a second thread it goes up to 0.4 seconds, which is still ok. From there on the results are decreasing. Adding a third thread brings alot of the queries up to 2 seonds. A forth thread, up to 4 seconds, a fifth spikes some of the queries up to 50 seconds. The CPU is roofing while this is going on, even on one thread. My test app takes some due to the speedy loop, and sql the rest. Which leads me to the conclusion that it won't scale very well. At least not on my tested hardware. Are there ways to optimize the database, say storing an array of int's per user instead of one record per item. But this makes it harder to remove items.

    Read the article

  • curl_init undefined?

    - by udaya
    Hi I am importing the contacts from gmail to my page ..... The process doesnot work due to this error 'curl_init' is not defined The suggestion i got is to 1.uncomment destination curl.dll 2.copy the following libraries to the windows/system32 dir. ssleay32.dll libeay32.dll 3.copy php_curl.dll to windows/system32 After trying all these i refreshed my xampp Even then error occurs This is my page where i am trying to import the gmail contacts ` // set URL and other appropriate options curl_setopt($ch, CURLOPT_URL, "http://www.example.com/"); curl_setopt($ch, CURLOPT_HEADER, 0); // grab URL and pass it to the browser curl_exec($ch); // close cURL resource, and free up system resources curl_close($ch); ? "HOSTED_OR_GOOGLE", "Email" = $_POST['Email'], echo "Passwd" = $_POST['Passwd'], "service" = "cp", "source" = "tutsmore/1.2" ); //Now we are going to post these datas to the clientLogin url. // Initialize the curl object with the $curl = curl_init($clientlogin_url); //Make the post true curl_setopt($curl, CURLOPT_POST, true); //Passing the above array of parameters. curl_setopt($curl, CURLOPT_POSTFIELDS, $clientlogin_post); //Set this for authentication and ssl communication. curl_setopt($curl, CURLOPT_HTTPAUTH, CURLAUTH_ANY); //provide false to not to check the server for the certificate. curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, false); //Tell curl to just don't echo the data but return it to a variable. curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1); //The variable containing response $response = curl_exec($curl); //Check whether the user is successfully login using the preg_match and save the auth key if the user //is successfully logged in preg_match("/Auth=([a-z0-9_-]+)/i", $response, $matches); $auth = $matches[1]; // Include the Auth string in the headers $headers = array("Authorization: GoogleLogin auth=" . $auth); // Make the request to the google contacts feed with the auth key $curl = curl_init('http://www.google.com/m8/feeds/contacts/default/full?max-results=10000'); //passing the headers of auth key. curl_setopt($curl, CURLOPT_HTTPHEADER, $headers); //Return the result in a variable curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1); //the variable with the response. $feed = curl_exec($curl); //Create empty array of contacts echo "contacts".$contacts=array(); //Initialize the DOMDocument object $doc=new DOMDocument(); //Check whether the feed is empty //If not empty then load that feed. if (!empty($feed)) $doc-loadHTML($feed); //Initialize the domxpath object and provide the loaded feed $xpath=new DOMXPath($doc); //Get every entry tags from the feed. $query="//entry"; $data=$xpath-query($query); //Process each entry tag foreach ($data as $node) { //children of each entry tag. $entry_nodes=$node-childNodes; //Create a temproray array. $tempArray=array(); //Process the child node of the entry tag. foreach($entry_nodes as $child) { //get the tagname of the child node. $domNodesName=$child-nodeName; switch($domNodesName) { case 'title' : { $tempArray['fullName']=$child-nodeValue; } break; case 'email' : { if (strpos($child-getAttribute('rel'),'home')!==false) $tempArray['email_1']=$child-getAttribute('address'); elseif(strpos($child-getAttribute('rel'),'work')!=false) $tempArray['email_2']=$child-getAttribute('address'); elseif(strpos($child-getAttribute('rel'),'other')!==false) $tempArray['email_3']=$child-getAttribute('address'); } break; } } if (!empty($tempArray['email_1']))$contacts[$tempArray['email_1']]=$tempArray; if(!empty($tempArray['email_2'])) $contacts[$tempArray['email_2']]=$tempArray; if(!empty($tempArray['email_3'])) $contacts[$tempArray['email_3']]=$tempArray; } foreach($contacts as $key=$val) { //Echo the email echo $key.""; } } else { //The form ? " method="POST" Email: Password: tutsmore don't save your email and password trust us. ` code is completely provided for debugging if any optimization is needed i will try to optimize the code

    Read the article

  • Getting a Temporary Table Returned from from Dynamic SQL in SQL Server 05, and parsing

    - by gloomy.penguin
    So I was requested to make a few things.... (it is Monday morning and for some reason this whole thing is turning out to be really hard for me to explain so I am just going to try and post a lot of my code; sorry) First, I needed a table: CREATE TABLE TICKET_INFORMATION ( TICKET_INFO_ID INT IDENTITY(1,1) NOT NULL, TICKET_TYPE INT, TARGET_ID INT, TARGET_NAME VARCHAR(100), INFORMATION VARCHAR(MAX), TIME_STAMP DATETIME DEFAULT GETUTCDATE() ) -- insert this row for testing... INSERT INTO TICKET_INFORMATION (TICKET_TYPE, TARGET_ID, TARGET_NAME, INFORMATION) VALUES (1,1,'RT_ID','IF_ID,int=1&IF_ID,int=2&OTHER,varchar(10)=val,ue3&OTHER,varchar(10)=val,ue4') The Information column holds data that needs to be parsed into a table. This is where I am having problems. In the resulting table, Target_Name needs to become a column that holds Target_ID as a value for each row in the resulting table. The string that needs to be parsed is in this format: @var_name1,@var_datatype1=@var_value1&@var_name2,@var_datatype2=@var_value2&@var_name3,@var_datatype3=@var_value3 And what I ultimately need as a result (in a table or table variable): RT_ID IF_ID OTHER 1 1 val,ue3 1 2 val,ue3 1 1 val,ue4 1 2 val,ue4 And I need to be able to join on the result. Initially, I was just going to make this a function that returns a table variable but for some reason I can't figure out how to get it into an actual table variable. Whatever parses the string needs to be able to be used directly in queries so I don't think a stored procedure is really the right thing to be using. This is the code that parses the Information string... it returns in a temporary table. -- create/empty temp table for var_name, var_type and var_value fields if OBJECT_ID('tempdb..#temp') is not null drop table #temp create table #temp (row int identity(1,1), var_name varchar(max), var_type varchar(30), var_value varchar(max)) -- just setting stuff up declare @target_name varchar(max), @target_id varchar(max), @info varchar(max) set @target_name = (select target_name from ticket_information where ticket_info_id = 1) set @target_id = (select target_id from ticket_information where ticket_info_id = 1) set @info = (select information from ticket_information where ticket_info_id = 1) --print @info -- some of these variables are re-used later declare @col_type varchar(20), @query varchar(max), @select as varchar(max) set @query = 'select ' + @target_id + ' as ' + @target_name + ' into #target; ' set @select = 'select * into ##global_temp from #target' declare @var_name varchar(100), @var_type varchar(100), @var_value varchar(100) declare @comma_pos int, @equal_pos int, @amp_pos int set @comma_pos = 1 set @equal_pos = 1 set @amp_pos = 0 -- while loop to parse the string into a table while @amp_pos < len(@info) begin -- get new comma position set @comma_pos = charindex(',',@info,@amp_pos+1) -- get new equal position set @equal_pos = charindex('=',@info,@amp_pos+1) -- set stuff that is going into the table set @var_name = substring(@info,@amp_pos+1,@comma_pos-@amp_pos-1) set @var_type = substring(@info,@comma_pos+1,@equal_pos-@comma_pos-1) -- get new ampersand position set @amp_pos = charindex('&',@info,@amp_pos+1) if @amp_pos=0 or @amp_pos<@equal_pos set @amp_pos = len(@info)+1 -- set last variable for insert into table set @var_value = substring(@info,@equal_pos+1,@amp_pos-@equal_pos-1) -- put stuff into the temp table insert into #temp (var_name, var_type, var_value) values (@var_name, @var_type, @var_value) -- is this a new field? if ((select count(*) from #temp where var_name = (@var_name)) = 1) begin set @query = @query + ' create table #' + @var_name + '_temp (' + @var_name + ' ' + @var_type + '); ' set @select = @select + ', #' + @var_name + '_temp ' end set @query = @query + ' insert into #' + @var_name + '_temp values (''' + @var_value + '''); ' end if OBJECT_ID('tempdb..##global_temp') is not null drop table ##global_temp exec (@query + @select) --select @query --select @select select * from ##global_temp Okay. So, the result I want and need is now in ##global_temp. How do I put all of that into something that can be returned from a function (or something)? Or can I get something more useful returned from the exec statement? In the end, the results of the parsed string need to be in a table that can be joined on and used... Ideally this would have been a view but I guess it can't with all the processing that needs to be done on that information string. Ideas? Thanks!

    Read the article

  • Javascript Closures - What are the negatives?

    - by vol7ron
    Question: There seem to be many benefits to Closures, but what are the negatives (memory leakage? obfuscation problems? bandwidth increasage?)? Additionally, is my understanding of Closures correct? Finally, once closures are created, can they be destroyed? I've been reading a little bit about Javascript Closures. I hope someone a little more knowledgeable will guide my assertions, correcting me where wrong. Benefits of Closures: Encapsulate the variables to a local scope, by using an internal function. The anonymity of the function is insignificant. What I've found helpful is to do some basic testing, regarding local/global scope: <script type="text/javascript"> var global_text = ""; var global_count = 0; var global_num1 = 10; var global_num2 = 20; var global_num3 = 30; function outerFunc() { var local_count = local_count || 0; alert("global_num1: " + global_num1); // global_num1: undefined var global_num1 = global_num1 || 0; alert("global_num1: " + global_num1); // global_num1: 0 alert("global_num2: " + global_num2); // global_num2: 20 global_num2 = global_num2 || 0; // (notice) no definition with 'var' alert("global_num2: " + global_num2); // global_num2: 20 global_num2 = 0; alert("local_count: " + local_count); // local_count: 0 function output() { global_num3++; alert("local_count: " + local_count + "\n" + "global_count: " + global_count + "\n" + "global_text: " + global_text ); local_count++; } local_count++; global_count++; return output; } var myFunc = outerFunc(); myFunc(); /* Outputs: ********************** * local_count: 1 * global_count: 1 * global_text: **********************/ global_text = "global"; myFunc(); /* Outputs: ********************** * local_count: 2 * global_count: 1 * global_text: global **********************/ var local_count = 100; myFunc(); /* Outputs: ********************** * local_count: 3 * global_count: 1 * global_text: global **********************/ alert("global_num1: " + global_num1); // global_num1: 10 alert("global_num2: " + global_num2); // global_num2: 0 alert("global_num3: " + global_num3); // global_num3: 33 </script> Interesting things I took out of it: The alerts in outerFunc are only called once, which is when the outerFunc call is assigned to myFunc (myFunc = outerFunc()). This assignment seems to keep the outerFunc open, in what I would like to call a persistent state. Everytime myFunc is called, the return is executed. In this case, the return is the internal function. Something really interesting is the localization that occurs when defining local variables. Notice the difference in the first alert between global_num1 and global_num2, even before the variable is trying to be created, global_num1 is considered undefined because the 'var' was used to signify a local variable to that function. -- This has been talked about before, in the order of operation for the Javascript engine, it's just nice to see this put to work. Globals can still be used, but local variables will override them. Notice before the third myFunc call, a global variable called local_count is created, but it as no effect on the internal function, which has a variable that goes by the same name. Conversely, each function call has the ability to modify global variables, as noticed by global_var3. Post Thoughts: Even though the code is straightforward, it is cluttered by alerts for you guys, so you can plug and play. I know there are other examples of closures, many of which use anonymous functions in combination with looping structures, but I think this is good for a 101-starter course to see the effects. The one thing I'm concerned with is the negative impact closures will have on memory. Because it keeps the function environment open, it is also keeping those variables stored in memory, which may/may not have performance implications, especially regarding DOM traversals and garbage collection. I'm also not sure what kind of role this will play in terms of memory leakage and I'm not sure if the closure can be removed from memory by a simple "delete myFunc;." Hope this helps someone, vol7ron

    Read the article

  • My IDE is showing "undeclared FileNotFoundException must be caught or thrown"

    - by Dan Czarnecki
    I am having the following issue above. I have tried actually putting a try-catch statement into the code as you will see below, but I can't get the compiler to get past that. import java.io.*; public class DirectoryStatistics extends DirectorySize { /* Dan Czarnecki October 24, 2013 Class variables: private File directory A File object that holds the pathname of the directory to look in private long sizeInBytes A variable of type long that holds the size of a file/directory (in bytes) private long fileCount A variable of type long that holds the number of files in a directory Constructors: public DirectoryStatistics(File startingDirectory) throws FileNotFoundException Creates a DirectoryStatistics object, given a pathname (inherited from DirectorySize class), and has 3 instance variables that hold the directory to search in, the size of each file (in bytes), and the number of files within the directory Modification history: October 24, 2013 Original version of class */ private File directory; private long sizeInBytes; private long fileCount; public DirectoryStatistics(File startingDirectory) throws FileNotFoundException { super(startingDirectory); try { if(directory == null) { throw new IllegalArgumentException("null input"); } if(directory.isDirectory() == false) { throw new FileNotFoundException("the following input is not a directory!"); } } catch(IOException ioe) { System.out.println("You have not entered a directory. Please try again."); } } public File getDirectory() { return this.directory; } public long getSizeInBytes() { return this.sizeInBytes; } public long getFileCount() { return this.fileCount; } public long setFileCount(long size) { fileCount = size; return size; } public long setSizeInBytes(long size) { sizeInBytes = size; return size; } public void incrementFileCount() { fileCount = fileCount + 1; } public void addToSizeInBytes(long addend) { sizeInBytes = sizeInBytes + addend; } public String toString() { return "Directory" + this.directory + "Size (in bytes) " + this.sizeInBytes + "Number of files: " + this.fileCount; } public int hashCode() { return this.directory.hashCode(); } public boolean equals(DirectoryStatistics other) { return this.equals(other); } } import java.io.*; import java.util.*; public class DirectorySize extends DirectoryProcessor { /* Dan Czarnecki October 17, 2013 Class variables: private Vector<Long> directorySizeList Variable of type Vector<Long> that holds the total file size of files in that directory as well as files within folders of that directory private Vector<File> currentFile Variable of type Vector<File> that holds the parent directory Constructors: public DirectorySize(File startingDirectory) throws FileNotFoundException Creates a DirectorySize object, takes in a pathname (inherited from DirectoryProcessor class, and has a single vector of a DirectoryStatistics object to hold the files and folders within a directory Modification History October 17, 2013 Original version of class Implemented run() and processFile() methods */ private Vector<DirectoryStatistics> directory; /* private Vector<Long> directorySizeList; private Vector<File> currentFile; */ public DirectorySize(File startingDirectory) throws FileNotFoundException { super(startingDirectory); directory = new Vector<DirectoryStatistics>(); } public void processFile(File file) { DirectoryStatistics parent; int index; File parentFile; System.out.println(file.getName()); System.out.println(file.getParent()); parentFile = file.getParentFile(); parent = new DirectoryStatistics(parentFile); System.out.println(parent); parent.equals(parent); index = directory.indexOf(parent); if(index == 0) { directory.elementAt(index).addToSizeInBytes(file.length()); directory.elementAt(index).incrementFileCount(); } if(index < 0) { directory.addElement(parent); directory.lastElement().setSizeInBytes(file.length()); directory.lastElement().incrementFileCount(); } Could someone tell me why I'm getting this issue?

    Read the article

  • Public class DiscoLight help

    - by luvthug
    Hi All, If some one can point me in the right direction for this code for my assigment I would really appreciate it. I have pasted the whole code that I need to complete but I need help with the following method public void changeColour(Circle aCircle) which is meant to allow to change the colour of the circle randomly, if 0 comes the light of the circle sgould change to red, 1 for green and 2 for purple. public class DiscoLight { /* instance variables */ private Circle light; // simulates a circular disco light in the Shapes window private Random randomNumberGenerator; /** * Default constructor for objects of class DiscoLight */ public DiscoLight() { super(); this.randomNumberGenerator = new Random(); } /** * Returns a randomly generated int between 0 (inclusive) * and number (exclusive). For example if number is 6, * the method will return one of 0, 1, 2, 3, 4, or 5. */ public int getRandomInt(int number) { return this.randomNumberGenerator.nextInt(number); } /** * student to write code and comment here for setLight(Circle) for Q4(i) */ public void setLight(Circle aCircle) { this.light = aCircle; } /** * student to write code and comment here for getLight() for Q4(i) */ public Circle getLight() { return this.light; } /** * Sets the argument to have a diameter of 50, an xPos * of 122, a yPos of 162 and the colour GREEN. * The method then sets the receiver's instance variable * light, to the argument aCircle. */ public void addLight(Circle aCircle) { //Student to write code here, Q4(ii) this.light = aCircle; this.light.setDiameter(50); this.light.setXPos(122); this.light.setYPos(162); this.light.setColour(OUColour.GREEN); } /** * Randomly sets the colour of the instance variable * light to red, green, or purple. */ public void changeColour(Circle aCircle) { //student to write code here, Q4(iii) if (getRandomInt() == 0) { this.light.setColour(OUColour.RED); } if (this.getRandomInt().equals(1)) { this.light.setColour(OUColour.GREEN); } else if (this.getRandomInt().equals(2)) { this.light.setColour(OUColour.PURPLE); } } /** * Grows the diameter of the circle referenced by the * receiver's instance variable light, to the argument size. * The diameter is incremented in steps of 2, * the xPos and yPos are decremented in steps of 1 until the * diameter reaches the value given by size. * Between each step there is a random colour change. The message * delay(anInt) is used to slow down the graphical interface, as required. */ public void grow(int size) { //student to write code here, Q4(iv) } /** * Shrinks the diameter of the circle referenced by the * receiver's instance variable light, to the argument size. * The diameter is decremented in steps of 2, * the xPos and yPos are incremented in steps of 1 until the * diameter reaches the value given by size. * Between each step there is a random colour change. The message * delay(anInt) is used to slow down the graphical interface, as required. */ public void shrink(int size) { //student to write code here, Q4(v) } /** * Expands the diameter of the light by the amount given by * sizeIncrease (changing colour as it grows). * * The method then contracts the light until it reaches its * original size (changing colour as it shrinks). */ public void lightCycle(int sizeIncrease) { //student to write code here, Q4(vi) } /** * Prompts the user for number of growing and shrinking * cycles. Then prompts the user for the number of units * by which to increase the diameter of light. * Method then performs the requested growing and * shrinking cycles. */ public void runLight() { //student to write code here, Q4(vii) } /** * Causes execution to pause by time number of milliseconds */ private void delay(int time) { try { Thread.sleep(time); } catch (Exception e) { System.out.println(e); } } }

    Read the article

  • Dispatcher Timer Problem

    - by will
    I am trying to make a game in silverlight that also has widgets in it. To do this I am using a dispatcher timer running a game loop that updates graphics etc. In this I have a variable that has to be accessed by both by the constantly running game loop and UI event code. At first look it seemed that the gameloop had its own local copy of currentUnit (the variable), despite the variable being declared globally. I am trying to update currentUnit with an event by the widget part of the app, but the timer's version of the variable is not being updated. What can I do get the currentUnit in the gameloop loop to be updated whenever I update currentUnit via a click event? Here is the code for setting currentUnit as part of a click event DataContractJsonSerializer serializer = new DataContractJsonSerializer(typeof(Unit)); currentUnit = serializer.ReadObject(e.Result) as Unit; txtName.Text = currentUnit.name; Canvas.SetLeft(txtName, 100 - (int)Math.Ceiling(txtName.ActualWidth) / 2); txtX.Text = "" + currentUnit.x; txtY.Text = "" + currentUnit.y; txtX.Text = "" + currentUnit.owner; txtY.Text = "" + currentUnit.moved; txtName.Text = "" + currentUnit.GetHashCode(); And here is a snippet from the gameLoop loop //deal with phase changes and showing stuff if (txtPhase.Text == "Move" && movementPanel.Visibility == Visibility.Collapsed) { if (currentUnit != null) { if (currentUnit.owner) { if (currentUnit.moved) { txtMoved.Text = "This Unit has Already Moved!"; movementPanel.Visibility = Visibility.Collapsed; } else { txtMoved.Text = "" + currentUnit.GetHashCode(); movementPanel.Visibility = Visibility.Visible; } } else { txtMoved.Text = "bam"; movementPanel.Visibility = Visibility.Collapsed; } } else { txtMoved.Text = "slam"; movementPanel.Visibility = Visibility.Collapsed; } //loadUnitList(); } Here is the code for my unit class. using System; public class Unit { public int id { get; set; } public string name { get; set; } public string image { get; set; } public int x { get; set; } public int y { get; set; } public bool owner { get; set; } public int rotation { get; set; } public double movement { get; set; } public string type { get; set; } public bool moved { get; set; } public bool fired { get; set; } } Overall, any simple types, like a double is being 'updated' correctly, yet a complex of my own type (Unit) seems to be holding a local copy. Please help, I've asked other places and no one has had an answer for me!

    Read the article

  • Why does Saxon evaluate the result-document URI to be the same?

    - by Jan
    My XSL source document looks like this <Topology> <Environment> <Id>test</Id> <Machines> <Machine> <Id>machine1</Id> <modules> <module>m1</module> <module>m2</module> </modules> </Machine> </Machines> </Environment> <Environment> <Id>production</Id> <Machines> <Machine> <Id>machine1</Id> <modules> <module>m1</module> <module>m2</module> </modules> </Machine> <Machine> <Id>machine2</Id> <modules> <module>m3</module> <module>m4</module> </modules> </Machine> </Machines> </Environment> </Topology> I want to create one result-document per machine, so I use the following stylesheet giving modelDir as path for the result-documents as parameter. <xsl:output method="xml" version="1.0" encoding="UTF-8" indent="yes" name="myXML" doctype-system="http://java.sun.com/dtd/properties.dtd"/> <xsl:template match="/"> <xsl:for-each-group select="/Topology/Environment/Machines/Machine" group-by="Id"> <xsl:variable name="machine" select="Id"/> <xsl:variable name="filename" select="concat($modelDir,$machine,'.xml')" /> <xsl:message terminate="no">Writing machine description to <xsl:value-of select="$filename"/></xsl:message> <xsl:result-document href="$filename" format="myXML"> <xsl:variable name="currentMachine" select="Id"/> <xsl:for-each select="current-group()/LogicalHosts/LogicalHost"> <xsl:variable name="environment" select="normalize-space(../../../../Id)"/> <xsl:message terminate="no">Module <xsl:value-of select="."/> for <xsl:value-of select="$environment"/></xsl:message> </xsl:for-each> </xsl:result-document> </xsl:for-each-group> </xsl:template> As my messages show me this seems to work fine - if saxon would not evaluate the URI of the result-document to be the same and thus give the following output. Writing machine description to target/build/model/m1.xml Module m1 for test Module m2 for test Module m1 for production Module m2 for production Writing machine description to target/build/model/m2.xml Error at xsl:result-document on line 29 of file:/C:/Projekte/.../machine.xsl: XTDE1490: Cannot write more than one result document to the same URI, or write to a URI that has been read: file:/C:/Projekte/.../$filename file:/C:/Projekte/.../machine.xsl(29,-1) : here Cannot write more than one result document to the same URI, or write to a URI that has been read: file:/C:/Projekte/.../$filename ; SystemID: file:/C:/Projekte/.../machine.xsl; Line#: 29; Column#: -1 net.sf.saxon.trans.DynamicError: Cannot write more than one result document to the same URI, or write to a URI that has been read: file:/C:/Projekte/.../$filename at net.sf.saxon.instruct.ResultDocument.processLeavingTail(ResultDocument.java:300) at net.sf.saxon.instruct.Block.processLeavingTail(Block.java:365) at net.sf.saxon.instruct.Instruction.process(Instruction.java:91) Any ideas on how to solve this?

    Read the article

  • Future of VB.NET? [closed]

    - by Alex Yeung
    Hi all, I worked with C# for years. Last year, I changed my job and the company use VB.NET. Of course, theoretically C# and VB.NET are very similar and I easily adapted. However, I have worked for VB.NET for 1 year. I cannot see any future of VB.NET. As a programming language, it is so foo. Here is a list of what C# can do but VB.NET cannot Case insensitive variables how to think a new variable name? If I have a property called FolderPath, i need to establish another private variable called _folderPath or m_folderPath. In C#, FolderPath and folderPath are two variables. Moreover, it gets compile error if variable name is same as a class name. For example Dim guid = Guid.NewGuid(). (What the...) Again, I need to think a new variable name. Adhoc scope In C#, we could use {...} to create a adhoc scope and all resource in {...} will not affect the code outside. However there is not such syntax in VB.NET. I could only use If True Then and End If to make a local scope which is so unclear. In-Method Region Sometime, it is unavoidable to have a long long method. VB.NET does not support in-method region. I always need to scroll down for 1000 lines. It wastes my time. No multi-line string definition In C#, we could var s = @"..." to define a multi-line string. In VB.NET there is no direct method to do that. The indirect way is use XML-literal string. Dim s = <![CDATA[...]]>.Value. However it is unclear. No block comment In C#, we have line comment // and block comment /* ... */. However in VB.NET we only have line comment which is a very big trouble for me. No statement end symbol Statements are separated by line break in VB.NET; while statements are separated by ; in C#. Underscore I think many people know underscore _ is continue statement symbol. I really disagree with that. I know MS VB.NET language team is going to remove the underscore syntax from VB.NET. However what can we do now? Although underscore is removed in the future, what's the advantage of that? I cannot see any advantage! With scope With scope is an evil scope. Although it allows shorter statement, it is hard to trace. Default Namesapce in project level It is a nightmare for me. The only advantage of VB.NET is property initialization. I think C# cannot do that (correct me if I am wrong.) Public Property ThisIsMyProperty As String = "MyValue" Remarks: I don't think optional method parameters is an advantage of OOP. By those disadvantages, I cannot see the future of VB.NET. Anyone sees the future of VB.NET?

    Read the article

  • Why don't I just build the whole web app in Javascript and Javascript HTML Templates?

    - by viatropos
    I'm getting to the point on an app where I need to start caching things, and it got me thinking... In some parts of the app, I render table rows (jqGrid, slickgrid, etc.) or fancy div rows (like in the New Twitter) by grabbing pure JSON and running it through something like Mustache, jquery.tmpl, etc. In other parts of the app, I just render the info in pure HTML (server-side HAML templates), and if there's searching/paginating, I just go to a new URL and load a new HTML page. Now the problem is in caching and maintainability. On one hand I'm thinking, if everything was built using Javascript HTML Templates, then my app would serve just an HTML layout/shell, and a bunch of JSON. If you look at the Facebook and Twitter HTML source, that's basically what they're doing (95% json/javascript, 5% html). This would make it so my app only needed to cache JSON (pages, actions, and/or records). Which means you'd hit the cache no matter if you were some remote api developer accessing a JSON api, or the strait web app. That is, I don't need 2 caches, one for the JSON, one for the HTML. That seems like it'd cut my cache store down in half, and streamline things a little bit. On the other hand, I'm thinking, from what I've seen/experienced, generating static HTML server-side, and caching that, seems to be much better performance wise cross-browser; you get the graphics instantly and don't have to wait that split-second for javascript to render it. StackOverflow seems to do everything in plain HTML, and you can tell... everything appears at once. Notice how though on twitter.com, the page is blank for .5-1 seconds, and the page chunks in: the javascript has to render the json. The downside with this is that, for anything dynamic (like endless scrolling, or grids), I'd have to create javascript templates anyway... so now I have server-side HAML templates, client-side javascript templates, and a lot more to cache. My question is, is there any consensus on how to approach this? What are the benefits and drawbacks from your experience of mixing the two versus going 100% with one over the other? Update: Some reasons that factor into why I haven't yet made the decision to go with 100% javascript templating are: Performance. Haven't formally tested, but from what I've seen, raw html renders faster and more fluidly than javascript-generated html cross-browser. Plus, I'm not sure how mobile devices handle dynamic html performance-wise. Testing. I have a lot of integration tests that work well with static HTML, so switching to javascript-only would require 1) more focused pure-javascript testing (jasmine), and 2) integrating javascript into capybara integration tests. This is just a matter of time and work, but it's probably significant. Maintenance. Getting rid of HAML. I love HAML, it's so easy to write, it prints pretty HTML... It makes code clean, it makes maintenance easy. Going with javascript, there's nothing as concise. SEO. I know google handles the ajax /#!/path, but haven't grasped how this will affect other search engines and how older browsers handle it. Seems like it'd require a significant setup.

    Read the article

  • Looking for best practise for writing a serial device communication app in C#

    - by cdotlister
    I am pretty new to serial comms, but would like advise on how to best achieve a robust application which speak to and listens to a serial device. I have managed to make use of System.IO.serialport, and successfully connected to, sent data to and recieved from my device. The way things work is this. My application connects to the Com Port and opens the port.... I then connect my device to the com port, and it detects a connectio to the PC, so sends a bit of text. it's really just copyright info, as well as the version of the firmware. I don't do anything with that, except display it in my 'activity' window. The device then waits. I can then query information, but sending a command such as 'QUERY PARAMETER1'. It then replies with something like: 'QUERY PARAMETER1\r\n\r\n76767\r\n\r\n' I then process that. I can then update it by sending 'SET PARAMETER1 12345', and it will reply with 'QUERY PARAMETER1\r\n\r\n12345\r\n\r\n'. All pretty basic. So, what I have done is created a Communication Class. this call is called in it's own thread, and sends data back to the main form... and also allows me to send messages to it. Sending data is easy. Recieving is a bit more tricky. I have employed the use of the datarecieved event, and when ever data comes in, I echo that to my screen. My problem is this: When I send a command, I feel I am being very dodgy in my handling. What I am doing is, lets say I am sending 'QUERY PARAMETER1'. I send the command to the device, I then put 'PARAMETER1' into a global variable, and I do a Thread.Sleep(100). On the data recieved, I then have a bit of logic that checks the incoming data, and sees if the string CONTAINS the value in the gloabl variable. As the reply may be 'QUERY PARAMETER1\r\n\r\n76767\r\n\r\n', it sees that it contains my parameter, parses the string, and returns the value I am looking for, but placing it into another global variable. My sending method was sleeping for 100ms. It then wakes, and checks the returned global variable. If it has data... then I'm happy, and I process the data. Problem is... if the sleep is too short.. it will fail. And I feel it's flakey.. putting stuff into variables.. then waiting... The other option is to use ReadLine instead, but that's very blocking. So I remove the datarecieved method, and instead... just send the data... then call ReadLine(). That may give me better results. There's no time, except when we connect initially, that data comes from the device, without me requesting it. So, maybe readline will be simpler and safer? Is this known as 'Blocking' reads? Also, can I set a timeout? Hopefully someone can guide me.

    Read the article

  • get user selection and convert it to a String [Android]

    - by Kira
    Hello, I just got a Droid, and after having used it for a while, I felt like I wanted to make a program for it. The program that I am trying to make calculates the actual storage capacity of secondary storage mediums. The user select from a list of units that ranges from KB to YB and the size the entered gets put into a formula depending on the chosen unit. However, there is a bit of a problem with the program. From my testing, I have narrowed it down to the fact that the user's selection is not really being obtained from the spinner. Everything I look up seems to point me to a method quite similar to how it works in J2SE, but it does nothing. How am I actually supposed to get that data? Here is the Java source code for the app: package com.Actual.android; import android.app.Activity; import android.os.Bundle; import android.widget.*; import android.view.*; public class ActualStorageActivity extends Activity { Spinner selection; /* declare variable, in order to control spinner (ComboBox) */ ArrayAdapter adapter; /* declare an array adapter object, in order for spinner to work */ EditText size; /* declare variable to control textfield */ EditText result; /* declare variable to control textfield */ Button calculate; /* declare variable to control button */ Storage capacity = new Storage(); /* import custom class for formulas */ /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); // load content from XML selection = (Spinner)findViewById(R.id.spinner); adapter = ArrayAdapter.createFromResource(this, R.array.choices_array, android.R.layout.simple_spinner_dropdown_item); size = (EditText)findViewById(R.id.size); result = (EditText)findViewById(R.id.result); calculate = (Button)findViewById(R.id.submit); adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item); /* set resource for dropdown */ selection.setAdapter(adapter); // attach adapter to spinner result.setEnabled(false); // make read-only result.setText("usable storage"); } public void calcAction(View view) { String initial = size.getText().toString(); String unit = selection.getSelectedItem().toString(); String end = "Nothing"; double convert = Double.parseDouble(initial); capacity.setStorage(convert); if (unit == "KB") { end = Double.toString(capacity.getKB()); } else if (unit == "MB") { end = Double.toString(capacity.getMB()); } else if (unit == "GB") { end = Double.toString(capacity.getGB()); } else if (unit == "TB") { end = Double.toString(capacity.getTB()); } else if (unit == "PB") { end = Double.toString(capacity.getPB()); } else if (unit == "EB") { end = Double.toString(capacity.getEB()); } else if (unit == "ZB") { end = Double.toString(capacity.getZB()); } else if (unit == "YB") { end = Double.toString(capacity.getYB()); } else; result.setText(end); } }

    Read the article

  • Looking for best practise for writing a serial device communication app

    - by cdotlister
    I am pretty new to serial comms, but would like advise on how to best achieve a robust application which speak to and listens to a serial device. I have managed to make use of System.IO.SerialPort, and successfully connected to, sent data to and recieved from my device. The way things work is this. My application connects to the Com Port and opens the port.... I then connect my device to the com port, and it detects a connection to the PC, so sends a bit of text. it's really just copyright info, as well as the version of the firmware. I don't do anything with that, except display it in my 'activity' window. The device then waits. I can then query information, but sending a command such as 'QUERY PARAMETER1'. It then replies with something like: 'QUERY PARAMETER1\r\n\r\n76767\r\n\r\n' I then process that. I can then update it by sending 'SET PARAMETER1 12345', and it will reply with 'QUERY PARAMETER1\r\n\r\n12345\r\n\r\n'. All pretty basic. So, what I have done is created a Communication Class. this call is called in it's own thread, and sends data back to the main form... and also allows me to send messages to it. Sending data is easy. Recieving is a bit more tricky. I have employed the use of the datarecieved event, and when ever data comes in, I echo that to my screen. My problem is this: When I send a command, I feel I am being very dodgy in my handling. What I am doing is, lets say I am sending 'QUERY PARAMETER1'. I send the command to the device, I then put 'PARAMETER1' into a global variable, and I do a Thread.Sleep(100). On the data received, I then have a bit of logic that checks the incoming data, and sees if the string CONTAINS the value in the global variable. As the reply may be 'QUERY PARAMETER1\r\n\r\n76767\r\n\r\n', it sees that it contains my parameter, parses the string, and returns the value I am looking for, but placing it into another global variable. My sending method was sleeping for 100ms. It then wakes, and checks the returned global variable. If it has data... then I'm happy, and I process the data. Problem is... if the sleep is too short.. it will fail. And I feel it's flaky.. putting stuff into variables.. then waiting... The other option is to use ReadLine instead, but that's very blocking. So I remove the data received method, and instead... just send the data... then call ReadLine(). That may give me better results. There's no time, except when we connect initially, that data comes from the device, without me requesting it. So, maybe ReadLine will be simpler and safer? Is this known as 'Blocking' reads? Also, can I set a timeout? Hopefully someone can guide me.

    Read the article

  • A view interface for large object/array dumps

    - by user685107
    I want to embed in a page a detailed structure report of my model objects, like print_r() or var_export() produce (now I’m doing this with running var_export() on get_object_vars()). But what I actually want to see is only some properties (in most cases), but at this moment I have to use Ctrl+F and seek the variable I want, instead of just staring at it right after the page completes loading. So I’m embedding buttons to show/hide large arrays etc. but thought: ‘What if there already is the thing I do right now?’ So is there? Update: What would your ideal interface look like? First of all, dumped models fit in the first screen. All the properties can be seen at the first look at the screen (there are not many of them, around 10 per each, three models total, so it is possible). Small arrays can be shown unrolled too. Let the size of the array to count it as ‘small’ be definable. Ideally, the user can see values of the properties without doing any click, scrolling the screen or typing something. There must be some improvements to representing the values, say, if an array is empty, show array ‘My_big_array’ is empty and if a boolean variable starting with is_, has_, had_ has a false as the value, make the variable (let us take is_available for example) shown as is_NOT_available in red, and if it has true as the value, show is_available in green. Without any value shown. The same goes for defined constants. That would be ideal. I want to make focus on this kind of switches. Krumo seems useful, but since it always closes up the variable without making difference of how large it is, I cannot use it as is, but there might appear something similar on github soon :) Second update starts here: Any programmer who sees is_available = false will know what it means, no need to do more Bringing in color indication I forgot about one thing: the ‘switches’ let’s call them so, may me important or not. So I have right now some of them that will show in green or red, this is for something global, like caching, which is shown as Caching is… ON with ‘ON’ written in green, (and ‘OFF’ in red when disabled) while the words about what it is, i.e. ‘Caching is… ’ are written in black. And some which are not so important, for example I haven’t defined REVEAL_TIES is… not set with ‘not set’ written in gray, while the words describing what it is stay in black. And if it would be set the whole phrase would be in black since there is nothing important: if this small utility for showing some undercover things is working, I will see some messages after it, if it isn’t — site will be working independently of its state. Dividing switches into important ones and not with corresponding color match should improve readability, especially for those users who are not programmers and just enabled debug mode because some guy from bugzilla said do that — for them it would help to understand what is important and what is not.

    Read the article

  • Connection drop problem with Hibernate-mysql-c3p0

    - by user344788
    hi all, This is an issue which I have seen all across the web. I will bring it up again as till now I don't have a fix for the same. I am using hibernate 3. mysql 5 and latest c3p0 jar. I am getting a broken pipe exception. Following is my hibernate.cfg file. com.mysql.jdbc.Driver org.hibernate.dialect.MySQLDialect <property name="hibernate.show_sql">true</property> <property name="hibernate.use_sql_comments">true</property> <property name="hibernate.current_session_context_class">thread</property> <property name="connection.autoReconnect">true</property> <property name="connection.autoReconnectForPools">true</property> <property name="connection.is-connection-validation-required">true</property> <!--<property name="c3p0.min_size">5</property> <property name="c3p0.max_size">20</property> <property name="c3p0.timeout">1800</property> <property name="c3p0.max_statements">50</property> --><property name="hibernate.connection.provider_class">org.hibernate.connection.C3P0ConnectionProvider </property> <property name="hibernate.c3p0.acquireRetryAttempts">30</property> <property name="hibernate.c3p0.acquireIncrement">5</property> <property name="hibernate.c3p0.automaticTestTable">C3P0TestTable</property> <property name="hibernate.c3p0.idleConnectionTestPeriod">36000</property> <property name="hibernate.c3p0.initialPoolSize">20</property> <property name="hibernate.c3p0.maxPoolSize">100</property> <property name="hibernate.c3p0.maxIdleTime">1200</property> <property name="hibernate.c3p0.maxStatements">50</property> <property name="hibernate.c3p0.minPoolSize">10</property>--> My connection pooling is occurring fine. During the day it is fine , but once i keep it idle over the night ,next day I find it giving me broken connection error. public class HibernateUtil { private static Logger log = Logger.getLogger(HibernateUtil.class); //private static Log log = LogFactory.getLog(HibernateUtil.class); private static Configuration configuration; private static SessionFactory sessionFactory; static { // Create the initial SessionFactory from the default configuration files try { log.debug("Initializing Hibernate"); // Read hibernate.properties, if present configuration = new Configuration(); // Use annotations: configuration = new AnnotationConfiguration(); // Read hibernate.cfg.xml (has to be present) configuration.configure(); // Build and store (either in JNDI or static variable) rebuildSessionFactory(configuration); log.debug("Hibernate initialized, call HibernateUtil.getSessionFactory()"); } catch (Throwable ex) { // We have to catch Throwable, otherwise we will miss // NoClassDefFoundError and other subclasses of Error log.error("Building SessionFactory failed.", ex); throw new ExceptionInInitializerError(ex); } } /** * Returns the Hibernate configuration that was used to build the SessionFactory. * * @return Configuration */ public static Configuration getConfiguration() { return configuration; } /** * Returns the global SessionFactory either from a static variable or a JNDI lookup. * * @return SessionFactory */ public static SessionFactory getSessionFactory() { String sfName = configuration.getProperty(Environment.SESSION_FACTORY_NAME); System.out.println("Current s name is "+sfName); if ( sfName != null) { System.out.println("Looking up SessionFactory in JNDI"); log.debug("Looking up SessionFactory in JNDI"); try { System.out.println("Returning new sssion factory"); return (SessionFactory) new InitialContext().lookup(sfName); } catch (NamingException ex) { throw new RuntimeException(ex); } } else if (sessionFactory == null) { System.out.println("calling rebuild session factory now"); rebuildSessionFactory(); } return sessionFactory; } /** * Closes the current SessionFactory and releases all resources. * <p> * The only other method that can be called on HibernateUtil * after this one is rebuildSessionFactory(Configuration). */ public static void shutdown() { log.debug("Shutting down Hibernate"); // Close caches and connection pools getSessionFactory().close(); // Clear static variables sessionFactory = null; } /** * Rebuild the SessionFactory with the static Configuration. * <p> * Note that this method should only be used with static SessionFactory * management, not with JNDI or any other external registry. This method also closes * the old static variable SessionFactory before, if it is still open. */ public static void rebuildSessionFactory() { log.debug("Using current Configuration to rebuild SessionFactory"); rebuildSessionFactory(configuration); } /** * Rebuild the SessionFactory with the given Hibernate Configuration. * <p> * HibernateUtil does not configure() the given Configuration object, * it directly calls buildSessionFactory(). This method also closes * the old static variable SessionFactory before, if it is still open. * * @param cfg */ public static void rebuildSessionFactory(Configuration cfg) { log.debug("Rebuilding the SessionFactory from given Configuration"); if (sessionFactory != null && !sessionFactory.isClosed()) sessionFactory.close(); if (cfg.getProperty(Environment.SESSION_FACTORY_NAME) != null) { log.debug("Managing SessionFactory in JNDI"); cfg.buildSessionFactory(); } else { log.debug("Holding SessionFactory in static variable"); sessionFactory = cfg.buildSessionFactory(); } configuration = cfg; } } Above is my code for the session factory. And I have only select operations . And below is the method which is used most often to execute my select queries. One tricky thing which I am not understanding is in my findById method i am using this line of code getSession().beginTransaction(); without which it gives me an error saying that this cannot happpen without a transaction. But nowhere I am closing this transaction. And thers no method to close a transaction apart from commit or rollback (as far as i know) which are not applicable for select statements. public T findById(ID id, boolean lock) throws HibernateException, DAOException { log.debug("findNyId invoked with ID ="+id+"and lock ="+lock); T entity; getSession().beginTransaction(); if (lock) entity = (T) getSession().load(getPersistentClass(), id, LockMode.UPGRADE); else entity = (T) getSession().load(getPersistentClass(), id); return entity; } Can anyone please suggest what can I do ? I have tried out almost every solution available via googling, on stackoverlow or on hibernate forums with no avail. (And increasing wait_timeout on mysql is not a valid option in my case).

    Read the article

< Previous Page | 187 188 189 190 191 192 193 194 195 196 197 198  | Next Page >