Search Results

Search found 13842 results on 554 pages for 'reference identity'.

Page 396/554 | < Previous Page | 392 393 394 395 396 397 398 399 400 401 402 403  | Next Page >

• C# thread safety for class instances

  - by Steveng

  I am learning C# and I am confused with the thread safety of the copies of the class instances as below: eg: classA objA; classA objB = objA; objA.field1 = value2; //do I need lock around modification of field1? //let say we pass the objB to another thread objB.field1 = value1 //do I need a lock for objB because of the modification of field1? I am confused because coming from the background of C++, the class in C# is the reference type. If both objA and objB refer to the same memory underlying, then I would need a lock to protect the simultaneous writing to the field1. Could someone confirm with this or am I missing something? Thanks.

  Read the article

• Any way to stringify a variable id / symbol in Python?

  - by otz

  I'm wondering if it is possible at all in python to stringify variable id/symbol -- that is, a function that behaves as follows: >>> symbol = 'whatever' >>> symbol_name(symbol) 'symbol' Now, it is easy to do it on a function or a class (if it is a direct reference to the object): >>> def fn(): pass >>> fn.func_name 'fn' But I'm looking for a general method that works on all cases, even for indirect object references. I've thought of somehow using id(var), but no luck yet. Is there any way to do it?

  Read the article

• What is the right way to implement communication between java objects?

  - by imoschak

  I'm working on an academic project which simulates a rather large queuing procedure in java. The core of the simulator rests within one package where there exist 8 classes, each one implementing a single concept. Every class in the project follows SRP. These classes encapsulate the behavior of the simulator and inter-connect every other class in the project. The problem that has arisen is that most of these 8 classes are, as is logical i think, tightly coupled and each one has to have working knowledge of every other class in this package in order to be able to call methods from it when needed. The application needs only one instance of each class so it might be better to create static fields for each class in a new class and use that to make calls -instead of preserving a reference in each class for every other class in the package (which I'm certain that is incorrect)-, but is this considered a correct design solution? or is there a design pattern maybe that better suits my needs?

  Read the article

• Handling orientation changes yourself

  - by synic

  From the documentation regarding the android:configChanges='orientation' attribute of the activity tag in the manifest: Note: Using this attribute should be avoided and used only as a last-resort. Please read Handling Runtime Changes for more information about how to properly handle a restart due to a configuration change. Why does it say this? In the case of threads and networking requests via a service API library, a request could be made with a reference to the original Activity, and then an orientation change could occur, leaving the thread pointing to the old Activity. While this can be fixed, it's tedious and ugly compared to just handling the configuration changes yourself. Why should it be avoided?

  Read the article

• how to use constants in SQL CREATE TABLE?

  - by kchiu

  Hi, I have 3 SQL tables, defined as follows: CREATE TABLE organs( abbreviation VARCHAR(16), -- ... other stuff ); CREATE TABLE blocks( abbreviation VARCHAR(16), -- ... other stuff ); CREATE TABLE slides( title VARCHAR(16), -- ... other stuff ); The 3 fields above all use VARCHAR(16) because they're related and have the same length restriction. Is there a (preferably portable) way to put '16' into a constant / variable and reference that instead in CREATE TABLE? eg. something like this would be nice: CREATE TABLE slides( title VARCHAR(MAX_TITLE_LENGTH), -- ... other stuff ); I'm using PostgreSQL 8.4. thanks a lot, and Happy New Year! cheers.

  Read the article

• C++ syntax of constructors " 'Object1 a (1, Object1(2))''

  - by osgx

  Hello I have a such syntax in program class Object1 : BaseClass { BaseClass *link; int i; public: Object1(int a){i=a;} Object1(int a, Object1 /*place1*/ o) {i=a; link= &o;} }; int main(){ Object1 a(1, /*place2*/ Object1(2)); ... } What do I need in place1? I want to save a link (pointer) to the second object in the first object. Should I use in place1 reference "&"? What type will have "Object1(2)" in place2? Is it a constructor of the anonymous object? Will it have a "auto" storage type?

  Read the article

• Class templating std::set key types

  - by TomFLuff

  I have a class to evaluate set algebra but wish to template it. At the minute it looks a bit like this set.h: template<typename T> class SetEvaluation { public: SetEvaluation<T>(); std::set<T> evaluate(std::string in_expression); } set.cpp template<typename T> std::set<T> SetEvaluation<T>::evaluate(std::string expression) { std::set<T> result; etc etc... } But i'm getting undefined reference errors when compiling. Is it possible to declare the return type as std::set<T> and then pass std::string as the class template param. There are no errors in the class but only when I try to instantiate SetEvaluation<std::string> Can anyone shed light on this problem? thanks

  Read the article

• SQL Server 2005 Reporting Services: How to count rows that are not null? Any hints for calculating t

  - by user329266

  Is there a way to count only records that are not null; similar to "COUNTA" in Excel? I would think this would be very simple process, but nothing I have tried has worked. If necessary, I can try to work this into my SQL query, but the query is already incredibly complicated. Also, I've found very little documentation for how to calculate report totals, and how to total from groups. Would anyone have any recommendations on what to use as a reference?

  Read the article

• Is "programmatically" a word? [closed]

  - by Lo'oris

  I can't find it on any of the online dictionaries I know: dict.org, word reference, urban dictionary, oxford paravia, garzanti. To my ears of a non-native speaker, it sounds horrible. Actually it sounds like a word made-up by another non-native speaker that wanted to say something, didn't know how, and just hacked in a word of his language. The only place I've read it other then user-created-content is the android documentation, so this might or might not be related. Do you happen to know where did it start to be used, why by did it spread so much, what does it really mean?

  Read the article

• Does this make any sense (Apple-documentation)?

  - by Paperflyer

  Here is a snippet of the official Apple Documentation of AudioBufferList (Core Audio Data Types Reference) AudioBufferList Holds a variable length array of AudioBuffer structures. struct AudioBufferList { UInt32 mNumberBuffers; AudioBuffer mBuffers[1]; }; typedef struct AudioBufferList AudioBufferList; Fields mNumberBuffers The number of AudioBuffer structures in the mBuffers array. mBuffers A variable length array of AudioBuffer structures. If mBuffers is defined as AudioBuffer[1] it is not of variable length and thus mNumberBuffers is implicitly defined as 1. Do I miss something here or is this just nonsense?

  Read the article

• Can I get.seed() somehow?

  - by a different ben

  In reference to the statement set.seed(), can I get the seed instead after running some code if I didn't set it explicitly? I've been re-running some code containing a function that randomises some sample of the input data (the function is part of the kohonen package). After playing with it for some time to see the variety of output (it was an 'unstable' problem), I noticed one result that was pretty interesting. I of course had not used set.seed(), but wondered if I could get the seed after running the code to reproduce the result? In ?set.seed I see .Random.seed saves the seed set for the uniform random-number generator But I don't know how that helps.

  Read the article

• Looking for a tutorial and/or example for the following: Annotation based Spring 3 with JPA and/or h

  - by Conor

  I want to learn Spring. I'd like to start with Spring 3. I want a simple tutorial and/or example. So no full blown web example please. Also - not a trivial example - so something incorporating persistence (e.g. JPA or hibernate) would be nice. Also - I don't want to get bogged down writing XML. So - Annotation based Spring 3 with JPA and/or hibernate. Yes - there is a good reference for Spring 3.0, but it's XML based. I can't find anything else useful. Thanks in advance.

  Read the article

• is it possible to create a multi-project template that references n number of existing projects and

  - by jcollum

  The situation: I need to create about 40+ solutions that all reference 3 projects and have one project that is unique to each one. I'd like to create a multi-project template that does this, but from what I've read it looks like it's very difficult or impossible (related SO question, but doesn't answer). I want my solution to look like this (names changed of course): These three are used by all solutions created under this "family": MyCompany.Extensions MyCompany.MyProject.Tests.Shared MyCompany.MyProject.Scripts This one is the one that makes the solution unique, 123, 124, 125 etc: MyCompany.MyProject.Tests.Unit123 Is it possible to set up a multi-project template that will generate this structure? References: MSDN Create Multi Project Templates

  Read the article

• Extendable accessing of sqlite database on android platform

  - by mscriven

  Hi, I am fairly new to the android sdk and databases and have been searching for an answer to this quite some time. I am trying to build an app which has multiple tables within a database. e.g. one for weapons, armours etc. However, my DatabaseManager class which handles all of my table creating, DatabaseHelper inner class and populating of data is creating for an extremely large class requiring high maintenance. Every time I would like to add or remove a table column I need to change quite a few areas of code, - Every reference to the addition of a row in that table with data - The method that the above calls - The method returning all of the database rows - The code in the helper class creating the table - Any specific update methods My question is this: Surely there must be some better way of coding this system, maybe using a database isn't the best way to go, or am i just not used to such large classes having only learned java at university and my largest class consisting of a mere 400-600 lines of code. Thanks for any help!

  Read the article

• Removing exception

  - by Nikhil K

  I have used this code for extracting urls from web page.But in the line of 'foreach' it is showing Object reference not set to an instance of an object exception. What is the problem? how can i correct that? WebClient client = new WebClient(); string url = "http://www.google.co.in/search?hl=en&q=java&start=10&sa=N"; string source = client.DownloadString(url); HtmlDocument doc = new HtmlDocument(); doc.LoadHtml(source); foreach (HtmlNode link in doc.DocumentNode.SelectNodes("//a[@href and @rel='nofollow']")) { Console.WriteLine(link.Attributes["href"].Value); }

  Read the article

• [GCC, linking] How to link app with static library + why this is not working

  - by user278799

  I have a problem. I wrote example code and I want to build it without the error: main.cpp.text+0x5): undefined reference to `test()' Library test1.c #include <stdlib.h> void test() { puts("Dziala"); } test1.h #ifndef TEST1_H #define TEST1_H extern void test(); #endif makefile all: gcc -c ./src/test1.c -o ./lib/test1.o ar rcs ./lib/libtest1.a ./lib/test1.o Program main.cpp #include <test1.h> int main() { test(); return 0; } makefile all: g++ -static -I../test1/include -L../test1/lib ./src/main.cpp -o ./build/MyApp -ltest1 What am I doing wrong?

  Read the article

• How to remove "index.php?" from HTACCESS [duplicate]

  - by Francis Goris

  This question already has an answer here: Reference: mod_rewrite, URL rewriting and “pretty links” explained 2 answers I have url like this: www.site.com/index.php?/genero/aventura/av/ But I would like this to be my new url: site.com/genero/aventura/av/ I used the following code: <IfModule mod_rewrite.c>RewriteEngine On RewriteCond %{HTTP_HOST} !^www.site.com/$ [NC] RewriteRule ^index.php\?/(.*)$ site.com/$1 [R=301,L] </IfModule> but only returns me: site.com/index.php?/genero/aventura/av/ This is my latest & full version: RewriteEngine on #RewriteCond $1 !^(index\.php|ver_capitulo\.html|google3436eb8eea8b8d6e\.html|BingSiteAuth\.xml |portadas|public|mp3|css|favicon\.ico|js|plantilla|i|swf|plugins|player\.swf|robots\.txt) RewriteCond $1 !^(index\.php|public|css|js|i|feed|portadas|robots\.txt|BingSiteAuth\.xml|plugins|i|mp3|favicon\.ico|pluginslist\.xml|google3436eb8eea8b8d6e\.html) RewriteRule ^(.*)$ /index.php?/$1 [L] #DirectoryIndex index.php #RewriteCond %{THE_REQUEST} http://www.page.com/index\.php [NC] #RewriteRule ^(.*?)index\.php$ http://page.com/$1 [L,R=301,NC,NE] #DirectoryIndex index.php #RewriteEngine On Thanks for reading.

  Read the article

• How does * work in Python

  - by Deqing

  Just switched from C++ to Python, and found that sometimes it is a little hard to understand ideas behind Python. I guess, a variable is a reference to the real object. For example, a=(1,2,5) meaning a - (1,2,5), so if b=a, then b and a are 2 references pointing to the same (1,2,5). It is a little like pointers in C/C++. If I have: def foo(a,b,c): print a,b,c a=(1,3,5) foo(*a) What does * mean here? Looks like it expands tuple a to a[0], a[1] and a[2]. But why print(*a) is not working while print(a[0],a[1],a[2]) works fine?

  Read the article

• Unit testing of static library that involves NSDocumentDirectory and other iOS App specific calls.

  - by Shiun

  Hi, I'm attempting to run unit tests for a static library that attempts to create/write/read a file in the document directory. Since this is a static library and not an application for the iOS, attempts to reference the NSDocumentDirectory is returning me directory for the form "/Users//Library/Application Support/iPhone Simulator/Documents" This directory does not exist. When attempting to access a directory from an actual application, the NSDocumentDirectory returns something of the form: "/Users//Library/Application Support/iPhone Simulator/4.2/FEDBEF5F-1326-4383-A087-CDA1B865E61A/Documents" (Please note the simulator version as well as application ID as part of the path) How can I overcome this shortcoming in the unit test framework for static libraries that implement tests that require iOS app specific calls? Thanks in advance.

  Read the article

• Difference between jQuery click, bind, live, delegate & trigger functions( with example)

  - by I Like PHP

  Hello All, I know there are a lot of questions similar to this, but I want to know clear difference between all of these jQuery functions together on this page with an example, so that it will be very helpful for me to understand the mechanism of all of these functions. I have also read the reference on jQuery main site, but there is no comparison between these: $().click(fn) $().bind('click',fn) $().live('click',fn) $().delegate('td','click',fn) $().trigger('click') // UPDATED Please do not refer any link if there is a part of question belong to that. Please describe how all four function exactly works in different manner, and which should be preferred in which situation. Note: If there are any other function with same functionality/mechanism , then please share. Thanks a lot. Update i have also seen $(trigger) function? is this works similar to above four function ?

  Read the article

• Downloading file using FTP client in BlackBerry

  - by AMUL

  Hi i am new to blackberry (7.0) environment. Recently i have been trying to download a file from the server on to the sdcard of the simulaotr through a FTP client. After searching a lot, i have not been able to find a reference for how to code a FTP. Can anyone please help or provide me a link where i can get a sample code of how to download a file using FTP. Also when i was working in Android environment previously, i made use of external jar file of FTP. But in Blackberry that same jar file is of no use. So please help me its part of my project...

  Read the article

• Why don't hardware failures show up at the programming language level?

  - by Julian Cienfuegos

  I am wondering if anyone can give my a good answer, or at least point me in the direction of a good reference to the following question: How come I have never heard of a computer breaking in a very fundamental way? How come when I declare x to be a double it stays as a double? How come there is never a short circuit that robs it of some bytes and makes it an integer? Why do we have faith that when we initialize x to 10, there will never be a power surge that will cause it to become 11, or something similar? I think I need a better understanding of memory. Thanks, and please don't bash me over the head for such a simple/abstract question.

  Read the article

• Purpose of front() and back() in assigning values in a Queue? (C++)

  - by kevin

  I have declared: queue<int, list<int> > Q After a series of calls: Q.push(37); Q.pop(); Q.push(19); Q.push(3); Q.push(13); Q.front(); Q.push(22); Q.push(8); Q.back(); I get: 19-3-13-22-8-NULL What I don't get is what the calls to Q.front() and Q.back() do. From what I understand, they return a reference to the first or last elements respectively, but I dont see how my list would be any different had those calls not been made. Do they have any effect? Sorry if this seems trivial, but I'm trying to figure out of those calls have a purpose, or of my professor is just trying to screw with me.

  Read the article

• .Net Compact Framework - is there any way in the SerialPort class to set the RTS control to TOGGLE ?

  - by egapotz

  Hi, I found very annoying the fact that the SerialPort class in the .NET Framework doesn't allow to set the rts control to TOGGLE. There is a property called RTSEnable that lets me control directly the status of the RTS signal, but in a Compact Framework app there is not much precision to make it work well. Another solution can be to write a class that calls unmanaged APIs and set the rts control via the DCB structure, but I don't like it since I am using some external libraries that need to reference to a SerialPort instance. Have you any other idea ? Thanks !

  Read the article

• How do I get back results running a VB Script from C#?

  - by Tom

  I want to be able to call VB scripts from C#, which is easy enough, but I need to be able to get back the results from these scripts at times. Should I use the method referenced with something to read back, or should I use a different method? I've found a method to getting data back from powershell scripts using Runspaces and Pipelines, but I don't know enough about this technology to know if it will work with VB scripts as well. Ideally, I'd like to do something similar to the powershell method where I can just pass in the contents of the script without needing to reference an external file and get back the results. Can anyone tell me how to do this? Thanks.

  Read the article

< Previous Page | 392 393 394 395 396 397 398 399 400 401 402 403  | Next Page >