Search Results

Search found 16445 results on 658 pages for 'array initialization'.

Page 5/658 | < Previous Page | 1 2 3 4 5 6 7 8 9 10 11 12  | Next Page >

  • MongoDB initialization error in Rails

    - by rube_noob
    I have an initialization script to set up my MongoDB connection in the config/initialization directory. It is my understanding that these initializers run after all of the plugins are initialized. The problem I am having is that when a particular plugin I am using is initialized, it tries to access the mongodb before I have set it up. I get this error: uninitialized class variable @@database_name in MongoMapper My question is: Where can I initialize Mongodb that will run after the mongodb gem has been loaded and before any of the plugins are initialized?

    Read the article

  • multi-dimension array value sorting in php

    - by David
    Another potentially interesting (or n00b, whatever comes first) question. I am building up an array with a set of database fields with information about table, actual field name and descriptive field name as a multi-dimensional array. Here is what it currently looks like: $Fields['User']['ID'] = "User ID"; $Fields['User']['FirstName'] = "First Name"; $Fields['Stats']['FavouriteOrder'] = "Favourite Item Ordered"; $Fields['Geographic']['Location'] = "Current Location"; $Fields['Geographic']['LocationCode'] = "Current Location Code"; Okay, this is fine, but I am piping this into a system that allows exporting of selected fields, and in the end I want to foreach() through the different levels, extract the data and then ultimately have all the descriptive fields to be displayed sorted alphabetically using their descriptive name. So ultimately in the order: Current Location, Current Location Code, Favourite Item Ordered, First Name then User ID - obviously keeping index associations. I can't use usort() and I can't use array_multisort()... or maybe I can and I just don't know how. usort() seems to need a key to sort by, but I have variable keys. array_multisort() just seems to do the same as sort() really. Any ideas?

    Read the article

  • how to change type of value in an php array and sorting it..is it possible ?

    - by justjoe
    hi, i got problem with my code and hopefully someone able to figure it out. The main purpose is to sort array based on its value (then reindex its numerical key). i got this sample of filename : $filename = array("index 198.php", "index 192.php", "index 144.php", "index 2.php", "index 1.php", "index 100.php", "index 111.php"); $alloutput = array(); //all of index in array foreach ($filename as $name) { preg_match('#(\d+)#', $name, $output); // take only the numerical from file name array_shift($output); // cleaned. the last code create duplicate numerical in $output, if (is_array($hasilku)) { $alloutput = array_merge($alloutput, $output); } } //try to check the type of every value in array foreach ($alloutput as $output) { if (is_array($hasil)) { echo "array true </br>"; } elseif (is_int($hasil)) { echo "integer true </br>"; } elseif (is_string($hasil)) { //the numerical taken from filename always resuld "string". echo "string true </br>"; } } the output of this code will be : Array ( [0] = 198 [1] = 192 [2] = 144 [3] = 2 [4] = 1 [5] = 100 [6] = 111 ) i have test every output in array. It's all string (and not numerical), So the question is how to change this string to integer, so i can sort it from the lowest into the highest number ? the main purpose of this code is how to output array where it had been sort from lowest to highest ?

    Read the article

  • How do I set up a .emacs initialization file? [migrated]

    - by Harry Weston
    I am using Linux Fedora 13 (Constantine) and emacs 23.1.1. I am trying to set up a .emacs file for initialization, by using emacs itself to edit and save a file .emacs in my home directory. However, although the file is there, emacs does not seem to recognize it. What might I be doing wrong, and is there a simple text for .emacs that will show me if it is being used, one that will display a message on emacs start up?

    Read the article

  • How to handle key in PhP array if the key contains japanese characters [migrated]

    - by Jim Thio
    I have this array: [ID] => ????????-???????????__35.79_139.72 [Email] => [InBuildingAddress] => [Price] => [Street] => [Title] => ???????? ??????????? [Website] => [Zip] => [Rating Star] => 0 [Rating Weight] => 0 [Latitude] => 35.7865334803033 [Longitude] => 139.716800710514 [Building] => [City] => Unknown_Japan [OpeningHour] => [TimeStamp] => 0000-00-00 00:00:00 [CountViews] => 0 Then I do something like this: $output[$info['ID']]=$info; //mess up here $tes=$info['ID']['Title']; Well guess what it messes up. Basically even though the content of an array in PhP can be Japanese. Is this true? What's wrong. The error I got is: Debug Warning: /sdfdsfdf/api/test2.php line 36 - Cannot find element ????????-???????????__35.79_139.72 in variable Debug Warning: /sdfdsfdf/api/test2.php line 36 - main() [function.main]: It is not safe to rely on the system's timezone settings. You are required to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'Asia/Krasnoyarsk' for '7.0/no DST' instead So many question mark Why is this happening. What's really going on inside PhP? Where can I learn more of such things. Most importantly, what would be the best way to handle this situation. Should I tell PhP to internally always use UTF-8? Does PhP array inherenty cannot use non ascii id?

    Read the article

  • Sorting a 2D array in obj-c?

    - by Debashis
    I have a 2D array as follows: [[@"string value", @"string value", NSInteger], [@"string value", @"string value", NSInteger], [@"string value", @"string value", NSInteger]] How would I sort the second dimension of arrays by the NSInteger?

    Read the article

  • Convert char array to int array c++

    - by Yadira Suazo
    I`m having problems converting a char array read from file to an int array. Maybe someone can help me. This is my code: char vectorPatron[67]; int iPatrones[67]; archivo = fopen("1_0.txt", "r"); for(i=0;i<67;i++){ fscanf(archivo, "%c", &vectorPatron[i]); printf("%c",vectorPatron[i]); } fclose(archivo); for(i=0;i<67;i++){ iPatrones[i] = atoi(&vectorPatron[i]); printf("%d",iPatrones[i]); }

    Read the article

  • Android java assigning 2d array to 3d array

    - by semajhan
    I'm running into problems trying to assign a 2d array to a 3d array, so I thought i'd ask a question about 3d and 2d arrays. Say I have a masterArray[][][] and wanted to put childArray1[][] and childArray2[][] into it. This is how I have done it and was wondering if that is the correct way of applying it: private int[][][] masterArray; private int[][] childArray1 = { {1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, {1, 1, 1, 0, 0, 1, 0, 1, 1, 1}, {1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, {1, 0, 1, 1, 1, 1, 1, 1, 0, 1}, {1, 0, 1, 1, 1, 1, 0, 1, 0, 1}, {1, 0, 1, 1, 0, 1, 0, 1, 0, 1}, {1, 0, 1, 1, 0, 1, 1, 1, 0, 1}, {1, 0, 1, 1, 1, 1, 1, 1, 0, 1}, {1, 0, 1, 1, 0, 1, 1, 1, 0, 1}, {1, 0, 1, 1, 0, 1, 8, 1, 0, 1}, {1, 0, 7, 1, 1, 1, 0, 1, 0, 1}, {1, 0, 1, 1, 1, 1, 0, 1, 0, 1}, {1, 0, 1, 1, 1, 1, 1, 1, 0, 1}, {1, 0, 0, 0, 0, 0, 0, 9, 0, 1}, {1, 1, 1, 1, 1, 1, 1, 1, 1, 1} }; private int[][] childArray2 = { {1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, {1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, {1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, {1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, {1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, {1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, {0, 0, 0, 0, 0, 0, 0, 0, 1, 1}, {1, 1, 1, 1, 7, 1, 1, 1, 1, 1}, {1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, {1, 1, 1, 1, 0, 1, 1, 1, 1, 1}, {1, 1, 1, 1, 0, 0, 0, 1, 1, 1}, {1, 1, 1, 9, 1, 1, 8, 0, 1, 1}, {1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, {1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, {1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, }; Ok, so in my init method I use these some methods to set the child arrays into the master array. What I was curious about was how this exactly works. I assumed the following: masterLevel = new int[MAX_LEVELS][MAP_WIDTH][MAP_HEIGHT]; for (int x = 0; x < MAP_WIDTH; x++) { for (int y = 0; y < MAP_HEIGHT; y++) { masterArray[currentLevel][x][y] = childArray1[x][y]; } } Would that work? In my application things aren't working so I picking out code that I am not 100% sure on.

    Read the article

  • Reverse subarray of an array with O(1)

    - by Babibu
    I have an idea how to implement sub array reverse with O(1), not including precalculation such as reading the input. I will have many reverse operations, and I can't use the trivial solution of O(N). Edit: To be more clear I want to build data structure behind the array with access layer that knows about reversing requests and inverts the indexing logic as necessary when someone wants to iterate over the array. Edit 2: The data structure will only be used for iterations I been reading this and this and even this questions but they aren't helping. There are 3 cases that need to be taking care of: Regular reverse operation Reverse that including reversed area Intersection between reverse and part of other reversed area in the array Here is my implementation for the first two parts, I will need your help with the last one. This is the rule class: class Rule { public int startingIndex; public int weight; } It is used in my basic data structure City: public class City { Rule rule; private static AtomicInteger _counter = new AtomicInteger(-1); public final int id = _counter.incrementAndGet(); @Override public String toString() { return "" + id; } } This is the main class: public class CitiesList implements Iterable<City>, Iterator<City> { private int position; private int direction = 1; private ArrayList<City> cities; private ArrayDeque<City> citiesQeque = new ArrayDeque<>(); private LinkedList<Rule> rulesQeque = new LinkedList<>(); public void init(ArrayList<City> cities) { this.cities = cities; } public void swap(int index1, int index2){ Rule rule = new Rule(); rule.weight = Math.abs(index2 - index1); cities.get(index1).rule = rule; cities.get(index2 + 1).rule = rule; } @Override public void remove() { throw new IllegalStateException("Not implemented"); } @Override public City next() { City city = cities.get(position); if (citiesQeque.peek() == city){ citiesQeque.pop(); changeDirection(); position += (city.rule.weight + 1) * direction; city = cities.get(position); } if(city.rule != null){ if(city.rule != rulesQeque.peekLast()){ rulesQeque.add(city.rule); position += city.rule.weight * direction; changeDirection(); citiesQeque.push(city); } else{ rulesQeque.removeLast(); position += direction; } } else{ position += direction; } return city; } private void changeDirection() { direction *= -1; } @Override public boolean hasNext() { return position < cities.size(); } @Override public Iterator<City> iterator() { position = 0; return this; } } And here is a sample program: public static void main(String[] args) { ArrayList<City> list = new ArrayList<>(); for(int i = 0 ; i < 20; i++){ list.add(new City()); } CitiesList citiesList = new CitiesList(); citiesList.init(list); for (City city : citiesList) { System.out.print(city + " "); } System.out.println("\n******************"); citiesList.swap(4, 8); for (City city : citiesList) { System.out.print(city + " "); } System.out.println("\n******************"); citiesList.swap(2, 15); for (City city : citiesList) { System.out.print(city + " "); } } How do I handle reverse intersections?

    Read the article

  • Array filteration PHP

    - by Muhammad Sajid
    I have an array with values like: Array ( [0] => Array ( [parent] => Basic [parentId] => 1 [child] => Birthday [childId] => 2 ) [1] => Array ( [parent] => Basic [parentId] => 1 [child] => Gender [childId] => 3 ) [2] => Array ( [parent] => Geo [parentId] => 10 [child] => Current City [childId] => 11 ) [3] => Array ( [parent] => Known me [parentId] => 5 [child] => My personality [childId] => 7 ) [4] => Array ( [parent] => Known me [parentId] => 5 [child] => Best life moment [childId] => 8 ) ) And I want to filter this array such that their filtration based on parent index, and the final result would be like: Array ( [0] => Array ( [parent] => Basic [parentId] => 1 [child] => Array ( [0] => Birthday [1] => Gender ) ) [1] => Array ( [parent] => Geo [parentId] => 10 [child] => Array ( [0] => Current City ) ) [2] => Array ( [parent] => Known me [parentId] => 5 [child] => Array ( [0] => My personality [1] => Best life moment ) ) ) For that I coded : $filter = array(); $f = 0; for ($i=0; $i<count($menuArray); $i++) { $c = 0; for( $b = 0; $b < count($filter); $b++ ){ if( $filter[$b]['parent'] == $menuArray[$i]['parent'] ){ $c++; } } if ($c == 0) { $filter[$f]['parent'] = $menuArray[$i]['parent']; $filter[$f]['parentId'] = $menuArray[$i]['parentId']; $filter[$f]['child'][] = $menuArray[$i]['child']; $f++; } } But it results : Array ( [0] => Array ( [parent] => Basic [parentId] => 1 [child] => Array ( [0] => Birthday ) ) [1] => Array ( [parent] => Geo [parentId] => 10 [child] => Array ( [0] => Current City ) ) [2] => Array ( [parent] => Known me [parentId] => 5 [child] => Array ( [0] => My personality ) ) ) Could anyone point out my missing LOC?

    Read the article

  • 3D array in a 2D array

    - by Smallbro
    Currently I've been using a 3D array for my tiles in a 2D world but the 3D side comes in when moving down into caves and whatnot. Now this is not memory efficient and I switched over to a 2D array and can now have much larger maps. The only issue I'm having now is that it seems that my tiles cannot occupy the same space as a tile on the same z level. My current structure means that each block has its own z variable. This is what it used to look like: map.blockData[x][y][z] = new Block(); however now it works like this map.blockData[x][y] = new Block(z); I'm not sure why but if I decide to use the same space on say the floor below it wont allow me to. Does anyone have any ideas on how I can add a z-axis to my 2D array? I'm using java but I reckon the concept carries across different languages.

    Read the article

  • [C++] A minimalistic smart array (container) class template

    - by legends2k
    I've written a (array) container class template (lets call it smart array) for using it in the BREW platform (which doesn't allow many C++ constructs like STD library, exceptions, etc. It has a very minimal C++ runtime support); while writing this my friend said that something like this already exists in Boost called MultiArray, I tried it but the ARM compiler (RVCT) cries with 100s of errors. I've not seen Boost.MultiArray's source, I've just started learning template only lately; template meta programming interests me a lot, although am not sure if this is strictly one, which can be categorised thus. So I want all my fellow C++ aficionados to review it ~ point out flaws, potential bugs, suggestions, optimisations, etc.; somthing like "you've not written your own Big Three which might lead to...". Possibly any criticism that'll help me improve this class and thereby my C++ skills. smart_array.h #include <vector> using std::vector; template <typename T, size_t N> class smart_array { vector < smart_array<T, N - 1> > vec; public: explicit smart_array(vector <size_t> &dimensions) { assert(N == dimensions.size()); vector <size_t>::iterator it = ++dimensions.begin(); vector <size_t> dimensions_remaining(it, dimensions.end()); smart_array <T, N - 1> temp_smart_array(dimensions_remaining); vec.assign(dimensions[0], temp_smart_array); } explicit smart_array(size_t dimension_1 = 1, ...) { static_assert(N > 0, "Error: smart_array expects 1 or more dimension(s)"); assert(dimension_1 > 1); va_list dim_list; vector <size_t> dimensions_remaining(N - 1); va_start(dim_list, dimension_1); for(size_t i = 0; i < N - 1; ++i) { size_t dimension_n = va_arg(dim_list, size_t); assert(dimension_n > 0); dimensions_remaining[i] = dimension_n; } va_end(dim_list); smart_array <T, N - 1> temp_smart_array(dimensions_remaining); vec.assign(dimension_1, temp_smart_array); } smart_array<T, N - 1>& operator[](size_t index) { assert(index < vec.size() && index >= 0); return vec[index]; } size_t length() const { return vec.size(); } }; template<typename T> class smart_array<T, 1> { vector <T> vec; public: explicit smart_array(vector <size_t> &dimension) : vec(dimension[0]) { assert(dimension[0] > 0); } explicit smart_array(size_t dimension_1 = 1) : vec(dimension_1) { assert(dimension_1 > 0); } T& operator[](size_t index) { assert(index < vec.size() && index >= 0); return vec[index]; } size_t length() { return vec.size(); } }; Sample Usage: #include <iostream> using std::cout; using std::endl; int main() { // testing 1 dimension smart_array <int, 1> x(3); x[0] = 0, x[1] = 1, x[2] = 2; cout << "x.length(): " << x.length() << endl; // testing 2 dimensions smart_array <float, 2> y(2, 3); y[0][0] = y[0][1] = y[0][2] = 0; y[1][0] = y[1][1] = y[1][2] = 1; cout << "y.length(): " << y.length() << endl; cout << "y[0].length(): " << y[0].length() << endl; // testing 3 dimensions smart_array <char, 3> z(2, 4, 5); cout << "z.length(): " << z.length() << endl; cout << "z[0].length(): " << z[0].length() << endl; cout << "z[0][0].length(): " << z[0][0].length() << endl; z[0][0][4] = 'c'; cout << z[0][0][4] << endl; // testing 4 dimensions smart_array <bool, 4> r(2, 3, 4, 5); cout << "z.length(): " << r.length() << endl; cout << "z[0].length(): " << r[0].length() << endl; cout << "z[0][0].length(): " << r[0][0].length() << endl; cout << "z[0][0][0].length(): " << r[0][0][0].length() << endl; // testing copy constructor smart_array <float, 2> copy_y(y); cout << "copy_y.length(): " << copy_y.length() << endl; cout << "copy_x[0].length(): " << copy_y[0].length() << endl; cout << copy_y[0][0] << "\t" << copy_y[1][0] << "\t" << copy_y[0][1] << "\t" << copy_y[1][1] << "\t" << copy_y[0][2] << "\t" << copy_y[1][2] << endl; return 0; }

    Read the article

  • A minimalistic smart array (container) class template

    - by legends2k
    I've written a (array) container class template (lets call it smart array) for using it in the BREW platform (which doesn't allow many C++ constructs like STD library, exceptions, etc. It has a very minimal C++ runtime support); while writing this my friend said that something like this already exists in Boost called MultiArray, I tried it but the ARM compiler (RVCT) cries with 100s of errors. I've not seen Boost.MultiArray's source, I've started learning templates only lately; template meta programming interests me a lot, although am not sure if this is strictly one that can be categorized thus. So I want all my fellow C++ aficionados to review it ~ point out flaws, potential bugs, suggestions, optimizations, etc.; something like "you've not written your own Big Three which might lead to...". Possibly any criticism that will help me improve this class and thereby my C++ skills. Edit: I've used std::vector since it's easily understood, later it will be replaced by a custom written vector class template made to work in the BREW platform. Also C++0x related syntax like static_assert will also be removed in the final code. smart_array.h #include <vector> #include <cassert> #include <cstdarg> using std::vector; template <typename T, size_t N> class smart_array { vector < smart_array<T, N - 1> > vec; public: explicit smart_array(vector <size_t> &dimensions) { assert(N == dimensions.size()); vector <size_t>::iterator it = ++dimensions.begin(); vector <size_t> dimensions_remaining(it, dimensions.end()); smart_array <T, N - 1> temp_smart_array(dimensions_remaining); vec.assign(dimensions[0], temp_smart_array); } explicit smart_array(size_t dimension_1 = 1, ...) { static_assert(N > 0, "Error: smart_array expects 1 or more dimension(s)"); assert(dimension_1 > 1); va_list dim_list; vector <size_t> dimensions_remaining(N - 1); va_start(dim_list, dimension_1); for(size_t i = 0; i < N - 1; ++i) { size_t dimension_n = va_arg(dim_list, size_t); assert(dimension_n > 0); dimensions_remaining[i] = dimension_n; } va_end(dim_list); smart_array <T, N - 1> temp_smart_array(dimensions_remaining); vec.assign(dimension_1, temp_smart_array); } smart_array<T, N - 1>& operator[](size_t index) { assert(index < vec.size() && index >= 0); return vec[index]; } size_t length() const { return vec.size(); } }; template<typename T> class smart_array<T, 1> { vector <T> vec; public: explicit smart_array(vector <size_t> &dimension) : vec(dimension[0]) { assert(dimension[0] > 0); } explicit smart_array(size_t dimension_1 = 1) : vec(dimension_1) { assert(dimension_1 > 0); } T& operator[](size_t index) { assert(index < vec.size() && index >= 0); return vec[index]; } size_t length() { return vec.size(); } }; Sample Usage: #include "smart_array.h" #include <iostream> using std::cout; using std::endl; int main() { // testing 1 dimension smart_array <int, 1> x(3); x[0] = 0, x[1] = 1, x[2] = 2; cout << "x.length(): " << x.length() << endl; // testing 2 dimensions smart_array <float, 2> y(2, 3); y[0][0] = y[0][1] = y[0][2] = 0; y[1][0] = y[1][1] = y[1][2] = 1; cout << "y.length(): " << y.length() << endl; cout << "y[0].length(): " << y[0].length() << endl; // testing 3 dimensions smart_array <char, 3> z(2, 4, 5); cout << "z.length(): " << z.length() << endl; cout << "z[0].length(): " << z[0].length() << endl; cout << "z[0][0].length(): " << z[0][0].length() << endl; z[0][0][4] = 'c'; cout << z[0][0][4] << endl; // testing 4 dimensions smart_array <bool, 4> r(2, 3, 4, 5); cout << "z.length(): " << r.length() << endl; cout << "z[0].length(): " << r[0].length() << endl; cout << "z[0][0].length(): " << r[0][0].length() << endl; cout << "z[0][0][0].length(): " << r[0][0][0].length() << endl; // testing copy constructor smart_array <float, 2> copy_y(y); cout << "copy_y.length(): " << copy_y.length() << endl; cout << "copy_x[0].length(): " << copy_y[0].length() << endl; cout << copy_y[0][0] << "\t" << copy_y[1][0] << "\t" << copy_y[0][1] << "\t" << copy_y[1][1] << "\t" << copy_y[0][2] << "\t" << copy_y[1][2] << endl; return 0; }

    Read the article

  • why i add more insignificant code but cost less time

    - by user3714382
    i write a method and when i add some insignificant code it works faster, like these : array[1]=array[1]; array[0]=array[0]; array[3]=array[3]; array[2]=array[2]; i use double t=System.currentTimeMillis(); at first to record the time. then call the method and use System.out.println(System.currentTimeMillis()-t); in the end. when i delete the code (array[1]=array[1];...) the cost time is 1035.0 ms,but if i add these code, the cost time become 898.0ms. here is my method and my code. PS:this method is use for the game 2048, exp: {2,2,2,2} trans to {0,0,4,4} static void toRight2(int[] array){ if (array[2]==array[3] ) { array[3]=array[2]*2; if (array[0]==array[1]) { array[2]=array[1]*2; array[0]=0; array[1]=0; }else { array[2]=array[1]; array[1]=array[0]; array[0]=0; } } else{ if (array[0]==array[1]) { array[1]=array[1]*2; array[0]=0; array[3]=array[3]; array[2]=array[2]; }else { array[1]=array[1];//delete this cost more time array[0]=array[0];//delete this cost more time array[3]=array[3];//delete this cost more time array[2]=array[2];//delete this cost more time } } } public static void main(String[] args) { double t=System.currentTimeMillis(); int[] array={1,2,3,3}; for (int j = 2; j <400*1000000; j++) { toRight2(array); } System.out.println(System.currentTimeMillis()-t); }

    Read the article

  • C++ - Constructor or Initialize Method to Startup

    - by Bob Fincheimer
    I want to determine when to do non-trivial initialization of a class. I see two times to do initialization: constructor and other method. I want to figure out when to use each. Choice 1: Constructor does initialization MyClass::MyClass(Data const& data) : m_data() { // does non-trivial initialization here } MyClass::~MyClass() { // cleans up here } Choice 2: Defer initialization to an initialize method MyClass::MyClass() : m_data() {} MyClass::Initialize(Data const& data) { // does non-trivial initialization here } MyClass::~MyClass() { // cleans up here } So to try and remove any subjectivity I want to figure out which is better in a couple of situations: Class that encapsulates a resource (window/font/some sort of handle) Class that composites resources to do something (a control/domain object) Data structure classes (tree/list/etc.) [Anything else you can think of] Things to analyze: Performance Ease of use by other developers How error-prone/opportunities for bugs [Anything else you can think of]

    Read the article

  • Is there any reason lazy initialization couldn't be built into Java?

    - by Renesis
    Since I'm working on a server with absolutely no non-persisted state for users, every User-related object we have is rolled out on every request. Consequently I often find myself doing lazy initialization of properties of objects that may go unused. protected EventDispatcher dispatcher = new EventDispatcher(); Becomes... protected EventDispatcher<EventMessage> dispatcher; public EventDispatcher<EventMessage> getEventDispatcher() { if (dispatcher == null) { dispatcher = new EventDispatcher<EventMessage>(); } return dispatcher; } Is there any reason this couldn't be built into Java? protected lazy EventDispatcher dispatcher = new EventDispatcher();

    Read the article

  • passing an array structure as an array

    - by Matias
    I'm having trouble passing a structure array as a parameter of a function struct Estructure{ int a; int b; }; and a funtion Begining(Estructure &s1[]) { //modifi the estructure s1 }; and the main would be something like this int main() { Estructure m[200]; Begining(m); }; is this valid?

    Read the article

  • How to solve lazy initialization exception using JPA and Hibernate as provider

    - by rupertin
    I am working on a project for a customer who wants to use lazy initialization. They always get "lazy initialization exception" when mapping classes with the default lazy loading mode. @JoinTable(name = "join_profilo_funzionalita", joinColumns = {@JoinColumn(name = "profilo_id", referencedColumnName = "profilo_id")}, inverseJoinColumns = {@JoinColumn(name = "funzionalita_id", referencedColumnName = "funzionalita_id")}) //@ManyToMany(fetch=FetchType.EAGER) - no exceptions if uncommented @ManyToMany private Collection<Funzionalita> funzionalitaIdCollection; Is there a standard pattern using JPA classes to avoid this error? Snippets are welcome, thanks a lot for your time.

    Read the article

  • initialization of objects in c++

    - by Happy Mittal
    I want to know, in c++, when does the initialization of objects take place? Is it at the compile time or link time? For ex: //file1.cpp extern int i; int j=5; //file2.cpp ( link with file1.cpp) extern j; int i=10; Now, what does compiler do : according to me, it allocates storage for variables. Now I want to know : does it also put initialization value in that storage or is it done at link time?

    Read the article

< Previous Page | 1 2 3 4 5 6 7 8 9 10 11 12  | Next Page >