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  • IconDownloader, problem with lazy downloading

    - by Junior B.
    My problem is simple to be described but it seems to be hard to solve. The problem is loading icons, with a custom class like IconDownloader.m provided by an official example from Apple, avoiding crashes if I release the view. I've added the IconDownloader class to my app, but it's clear that this approach is good only if the tableview is the root. The big problem is when the view is not the root one. F.e: if I start to scroll my second view (the app now load the icons) and, without leaving it the time to finish the download, I go back to root, the app crash because the view that have to be updated with new icons doesn't exist anymore. One possible solution could be implement an OperationQueue in the view, but with this approach I've to stop the queue when I change the view and restart it when I come back and the idea to have N queues don't make me enthusiastic. Anyone found a good solution for this problem?

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  • How to lazy load a data structure (python)

    - by Anton Geraschenko
    I have some way of building a data structure (out of some file contents, say): def loadfile(FILE): return # some data structure created from the contents of FILE So I can do things like puppies = loadfile("puppies.csv") # wait for loadfile to work kitties = loadfile("kitties.csv") # wait some more print len(puppies) print puppies[32] In the above example, I wasted a bunch of time actually reading kitties.csv and creating a data structure that I never used. I'd like to avoid that waste without constantly checking if not kitties whenever I want to do something. I'd like to be able to do puppies = lazyload("puppies.csv") # instant kitties = lazyload("kitties.csv") # instant print len(puppies) # wait for loadfile print puppies[32] So if I don't ever try to do anything with kitties, loadfile("kitties.csv") never gets called. Is there some standard way to do this? After playing around with it for a bit, I produced the following solution, which appears to work correctly and is quite brief. Are there some alternatives? Are there drawbacks to using this approach that I should keep in mind? class lazyload: def __init__(self,FILE): self.FILE = FILE self.F = None def __getattr__(self,name): if not self.F: print "loading %s" % self.FILE self.F = loadfile(self.FILE) return object.__getattribute__(self.F, name) What might be even better is if something like this worked: class lazyload: def __init__(self,FILE): self.FILE = FILE def __getattr__(self,name): self = loadfile(self.FILE) # this never gets called again # since self is no longer a # lazyload instance return object.__getattribute__(self, name) But this doesn't work because self is local. It actually ends up calling loadfile every time you do anything.

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  • ExtJS (4.0) dynamic / lazy loading

    - by Paul
    Given a border layout with a west (navigation) and a center region. Let say I click on topic A in the west region, I want to replace (replace as in 'delete last topic') the center region with 'extjs' program code named topic_a.js I succeed in loading with this code: dynamicPanel = new Ext.Component({ loader: { url: '/www/file.htm', renderer: 'html', autoLoad: true, scripts: true } }); var oMainContainer = Ext.getCmp('maincontainer'); oMainContainer.show(); oMainContainer.add(dynamicPanel); But calling this the second time 'adds' things up in the center region and of course fails short in 'deleting', what would be a good approach?

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  • Odd ActiveRecord model dynamic initialization bug in production

    - by qfinder
    I've got an ActiveRecord (2.3.5) model that occasionally exhibits incorrect behavior that appears to be related to a problem in its dynamic initialization. Here's the code: class Widget < ActiveRecord::Base extend ActiveSupport::Memoizable serialize :settings VALID_SETTINGS = %w(show_on_sale show_upcoming show_current show_past) VALID_SETTINGS.each do |setting| class_eval %{ def #{setting}=(val); self.settings[:#{setting}] = (val == "1"); end def #{setting}; self.settings[:#{setting}]; end } end def initialize_settings self.settings ||= { :show_on_sale => true, :show_upcoming => true } end after_initialize :initialize_settings # All the other stuff the model does end The idea was to use a single record field (settings) to persist a bunch of configuration data for this object, but allow all the settings to seamlessly work with form helpers and the like. (Why this approach makes sense here is a little out of scope, but let's assume that it does.) Net-net, Widget should end up with instance methods (eg #show_on_sale= #show_on_sale) for all the entires in the VALID_SETTINGS array. Any default values should be specified in initialize_settings. And indeed this works, mostly. In dev and staging, no problems at all. But in production, the app sometimes ends up in a state where a) any writes to the dynamically generated setters fail and b) none of the default values appear to be set - although my leading theory is that the dynamically generated reader methods are just broken. The code, db, and environment is otherwise identical between the three. A typical error message / backtrace on the fail looks like: IndexError: index 141145 out of string (eval):2:in []=' (eval):2:inshow_on_sale=' [GEM_ROOT]/gems/activerecord-2.3.5/lib/active_record/base.rb:2746:in send' [GEM_ROOT]/gems/activerecord-2.3.5/lib/active_record/base.rb:2746:inattributes=' [GEM_ROOT]/gems/activerecord-2.3.5/lib/active_record/base.rb:2742:in each' [GEM_ROOT]/gems/activerecord-2.3.5/lib/active_record/base.rb:2742:inattributes=' [GEM_ROOT]/gems/activerecord-2.3.5/lib/active_record/base.rb:2634:in `update_attributes!' ...(then controller and all the way down) Ideas or theories as to what might be going on? My leading theory is that something is going wrong in instance initialization wherein the class instance variable settings is ending up as a string rather than a hash. This explains both the above setter failure (:show_on_sale is being used to index into the string) and the fact that getters don't work (an out of bounds [] call on a string just returns nil). But then how and why might settings occasionally end up as a string rather than hash?

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  • C++ Array Initialization in Function Call or Constructor Call

    - by david
    This question is related to the post here. Is it possible to initialize an array in a function call or constructor call? For example, class foo's constructor wants an array of size 3, so I want to call foo( { 0, 0, 0 } ). I've tried this, and it does not work. I'd like to be able to initialize objects of type foo in other objects' constructor initialization lists, or initialize foo's without first creating a separate array. Is this possible?

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  • C++ array initialization without assignment

    - by david
    This question is related to the post here. Is it possible to initialize an array without assigning it? For example, class foo's constructor wants an array of size 3, so I want to call foo( { 0, 0, 0 } ). I've tried this, and it does not work. I'd like to be able to initialize objects of type foo in other objects' constructor initialization lists. Is this possible?

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  • C#: System.Lazy&lt;T&gt; and the Singleton Design Pattern

    - by James Michael Hare
    So we've all coded a Singleton at one time or another.  It's a really simple pattern and can be a slightly more elegant alternative to global variables.  Make no mistake, Singletons can be abused and are often over-used -- but occasionally you find a Singleton is the most elegant solution. For those of you not familiar with a Singleton, the basic Design Pattern is that a Singleton class is one where there is only ever one instance of the class created.  This means that constructors must be private to avoid users creating their own instances, and a static property (or method in languages without properties) is defined that returns a single static instance. 1: public class Singleton 2: { 3: // the single instance is defined in a static field 4: private static readonly Singleton _instance = new Singleton(); 5:  6: // constructor private so users can't instantiate on their own 7: private Singleton() 8: { 9: } 10:  11: // read-only property that returns the static field 12: public static Singleton Instance 13: { 14: get 15: { 16: return _instance; 17: } 18: } 19: } This is the most basic singleton, notice the key features: Static readonly field that contains the one and only instance. Constructor is private so it can only be called by the class itself. Static property that returns the single instance. Looks like it satisfies, right?  There's just one (potential) problem.  C# gives you no guarantee of when the static field _instance will be created.  This is because the C# standard simply states that classes (which are marked in the IL as BeforeFieldInit) can have their static fields initialized any time before the field is accessed.  This means that they may be initialized on first use, they may be initialized at some other time before, you can't be sure when. So what if you want to guarantee your instance is truly lazy.  That is, that it is only created on first call to Instance?  Well, there's a few ways to do this.  First we'll show the old ways, and then talk about how .Net 4.0's new System.Lazy<T> type can help make the lazy-Singleton cleaner. Obviously, we could take on the lazy construction ourselves, but being that our Singleton may be accessed by many different threads, we'd need to lock it down. 1: public class LazySingleton1 2: { 3: // lock for thread-safety laziness 4: private static readonly object _mutex = new object(); 5:  6: // static field to hold single instance 7: private static LazySingleton1 _instance = null; 8:  9: // property that does some locking and then creates on first call 10: public static LazySingleton1 Instance 11: { 12: get 13: { 14: if (_instance == null) 15: { 16: lock (_mutex) 17: { 18: if (_instance == null) 19: { 20: _instance = new LazySingleton1(); 21: } 22: } 23: } 24:  25: return _instance; 26: } 27: } 28:  29: private LazySingleton1() 30: { 31: } 32: } This is a standard double-check algorithm so that you don't lock if the instance has already been created.  However, because it's possible two threads can go through the first if at the same time the first time back in, you need to check again after the lock is acquired to avoid creating two instances. Pretty straightforward, but ugly as all heck.  Well, you could also take advantage of the C# standard's BeforeFieldInit and define your class with a static constructor.  It need not have a body, just the presence of the static constructor will remove the BeforeFieldInit attribute on the class and guarantee that no fields are initialized until the first static field, property, or method is called.   1: public class LazySingleton2 2: { 3: // because of the static constructor, this won't get created until first use 4: private static readonly LazySingleton2 _instance = new LazySingleton2(); 5:  6: // Returns the singleton instance using lazy-instantiation 7: public static LazySingleton2 Instance 8: { 9: get { return _instance; } 10: } 11:  12: // private to prevent direct instantiation 13: private LazySingleton2() 14: { 15: } 16:  17: // removes BeforeFieldInit on class so static fields not 18: // initialized before they are used 19: static LazySingleton2() 20: { 21: } 22: } Now, while this works perfectly, I hate it.  Why?  Because it's relying on a non-obvious trick of the IL to guarantee laziness.  Just looking at this code, you'd have no idea that it's doing what it's doing.  Worse yet, you may decide that the empty static constructor serves no purpose and delete it (which removes your lazy guarantee).  Worse-worse yet, they may alter the rules around BeforeFieldInit in the future which could change this. So, what do I propose instead?  .Net 4.0 adds the System.Lazy type which guarantees thread-safe lazy-construction.  Using System.Lazy<T>, we get: 1: public class LazySingleton3 2: { 3: // static holder for instance, need to use lambda to construct since constructor private 4: private static readonly Lazy<LazySingleton3> _instance 5: = new Lazy<LazySingleton3>(() => new LazySingleton3()); 6:  7: // private to prevent direct instantiation. 8: private LazySingleton3() 9: { 10: } 11:  12: // accessor for instance 13: public static LazySingleton3 Instance 14: { 15: get 16: { 17: return _instance.Value; 18: } 19: } 20: } Note, you need your lambda to call the private constructor as Lazy's default constructor can only call public constructors of the type passed in (which we can't have by definition of a Singleton).  But, because the lambda is defined inside our type, it has access to the private members so it's perfect. Note how the Lazy<T> makes it obvious what you're doing (lazy construction), instead of relying on an IL generation side-effect.  This way, it's more maintainable.  Lazy<T> has many other uses as well, obviously, but I really love how elegant and readable it makes the lazy Singleton.

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  • Java: initialization problem with private-final-int-value and empty constructor

    - by HH
    $ javac InitInt.java InitInt.java:7: variable right might not have been initialized InitInt(){} ^ 1 error $ cat InitInt.java import java.util.*; import java.io.*; public class InitInt { private final int right; InitInt(){} public static void main(String[] args) { // I don't want to assign any value. // just initialize it, how? InitInt test = new InitInt(); System.out.println(test.getRight()); // later assiging a value } public int getRight(){return right;} } Initialization problem with Constructor InitInt{ // Still the error, "may not be initialized" // How to initialise it? if(snippetBuilder.length()>(charwisePos+25)){ right=charwisePos+25; }else{ right=snippetBuilder.length()-1; } }

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  • Java: conditional initialization?

    - by HH
    Ruby has conditional initialization. Apparently, Java does not or does it? I try to write more succintly, to limit the range as small as possible. import java.io.*; import java.util.*; public class InitFor{ public static void main(String[] args){ for(int i=7,k=999;i+((String h="hello").size())<10;i++){} System.out.println("It should be: hello = "+h); } } Errors Press ENTER or type command to continue InitFor.java:8: ')' expected for(int i=7,k=999;i+((String h="hello").size())<10;i++){} ^

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  • prevent using functions before initialization, constructors-like in C

    - by Hernán Eche
    This is the way I get to prevent funA,funB,funC, etc.. for being used before init #define INIT_KEY 0xC0DE //any number except 0, is ok static int initialized=0; int Init() { //many init task initialized=INIT_KEY; } int funA() { if (initialized!=INIT_KEY) return 1 //.. } int funB() { if (initialized!=INIT_KEY) return 1 //.. } int funC() { if (initialized!=INIT_KEY) return 1 //.. } The problem with this approach is that if some of those function is called within a loop so "if (initialized!=INIT_KEY)" is called again, and again, although it's not necessary. It's a good example of why constructors are useful haha, If it were an object I would be sure that when was created initialization was called, but in C, I don't know how to do it. Any other ideas are welcome!

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  • Hidden divs for "lazy javascript" loading? Possible security/other issues?

    - by xyld
    I'm curious about people's opinion's and thoughts about this situation. The reason I'd like to lazy load javascript is because of performance. Loading javascript at the end of the body reduces the browser blocking and ends up with much faster page loads. But there is some automation I'm using to generate the html (django specifically). This automation has the convenience of allowing forms to be built with "Widgets" that output content it needs to render the entire widget (extra javascript, css, ...). The problem is that the widget wants to output javascript immediately into the middle of the document, but I want to ensure all javascript loads at the end of the body. When the following widget is added to a form, you can see it renders some <script>...</script> tags: class AutoCompleteTagInput(forms.TextInput): class Media: css = { 'all': ('css/jquery.autocomplete.css', ) } js = ( 'js/jquery.bgiframe.js', 'js/jquery.ajaxQueue.js', 'js/jquery.autocomplete.js', ) def render(self, name, value, attrs=None): output = super(AutoCompleteTagInput, self).render(name, value, attrs) page_tags = Tag.objects.usage_for_model(DataSet) tag_list = simplejson.dumps([tag.name for tag in page_tags], ensure_ascii=False) return mark_safe(u'''<script type="text/javascript"> jQuery("#id_%s").autocomplete(%s, { width: 150, max: 10, highlight: false, scroll: true, scrollHeight: 100, matchContains: true, autoFill: true }); </script>''' % (name, tag_list,)) + output What I'm proposing is that if someone uses a <div class=".lazy-js">...</div> with some css (.lazy-js { display: none; }) and some javascript (jQuery('.lazy-js').each(function(index) { eval(jQuery(this).text()); }), you can effectively force all javascript to load at the end of page load: class AutoCompleteTagInput(forms.TextInput): class Media: css = { 'all': ('css/jquery.autocomplete.css', ) } js = ( 'js/jquery.bgiframe.js', 'js/jquery.ajaxQueue.js', 'js/jquery.autocomplete.js', ) def render(self, name, value, attrs=None): output = super(AutoCompleteTagInput, self).render(name, value, attrs) page_tags = Tag.objects.usage_for_model(DataSet) tag_list = simplejson.dumps([tag.name for tag in page_tags], ensure_ascii=False) return mark_safe(u'''<div class="lazy-js"> jQuery("#id_%s").autocomplete(%s, { width: 150, max: 10, highlight: false, scroll: true, scrollHeight: 100, matchContains: true, autoFill: true }); </div>''' % (name, tag_list,)) + output Nevermind all the details of my specific implementation (the specific media involved), I'm looking for a consensus on whether the method of using lazy-loaded javascript through hidden a hidden tags can pose issues whether security or other related? One of the most convenient parts about this is that it follows the DRY principle rather well IMO because you don't need to hack up a specific lazy-load for each instance in the page. It just "works". UPDATE: I'm not sure if django has the ability to queue things (via fancy template inheritance or something?) to be output just before the end of the </body>?

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  • Java - Class type from inside static initialization block

    - by DutrowLLC
    Is it possible to get the class type from inside the static initialization block? This is a simplified version of what I currently have:: class Person extends SuperClass { String firstName; static{ // This function is on the "SuperClass": // I'd for this function to be able to get "Person.class" without me // having to explicitly type it in but "this.class" does not work in // a static context. doSomeReflectionStuff(Person.class); // IN "SuperClass" } } This is closer to what I am doing, which is to initialize a data structure that holds information about the object and its annotations, etc... Perhaps I am using the wrong pattern? public abstract SuperClass{ static void doSomeReflectionStuff( Class<?> classType, List<FieldData> fieldDataList ){ Field[] fields = classType.getDeclaredFields(); for( Field field : fields ){ // Initialize fieldDataList } } } public abstract class Person { @SomeAnnotation String firstName; // Holds information on each of the fields, I used a Map<String, FieldData> // in my actual implementation to map strings to the field information, but that // seemed a little wordy for this example static List<FieldData> fieldDataList = new List<FieldData>(); static{ // Again, it seems dangerous to have to type in the "Person.class" // (or Address.class, PhoneNumber.class, etc...) every time. // Ideally, I'd liken to eliminate all this code from the Sub class // since now I have to copy and paste it into each Sub class. doSomeReflectionStuff(Person.class, fieldDataList); } }

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  • non-copyable objects and value initialization: g++ vs msvc

    - by R Samuel Klatchko
    I'm seeing some different behavior between g++ and msvc around value initializing non-copyable objects. Consider a class that is non-copyable: class noncopyable_base { public: noncopyable_base() {} private: noncopyable_base(const noncopyable_base &); noncopyable_base &operator=(const noncopyable_base &); }; class noncopyable : private noncopyable_base { public: noncopyable() : x_(0) {} noncopyable(int x) : x_(x) {} private: int x_; }; and a template that uses value initialization so that the value will get a known value even when the type is POD: template <class T> void doit() { T t = T(); ... } and trying to use those together: doit<noncopyable>(); This works fine on msvc as of VC++ 9.0 but fails on every version of g++ I tested this with (including version 4.5.0) because the copy constructor is private. Two questions: Which behavior is standards compliant? Any suggestion of how to work around this in gcc (and to be clear, changing that to T t; is not an acceptable solution as this breaks POD types). P.S. I see the same problem with boost::noncopyable.

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  • C++: Construction and initialization order guarantees

    - by Helltone
    Hi, I have some doubts about construction and initialization order guarantees in C++. For instance, the following code has four classes X, Y, Z and W. The main function instantiates an object of class X. X contains an object of class Y, and derives from class Z, so both constructors will be called. Additionally, the const char* parameter passed to X's constructor will be implicitly converted to W, so W's constructor must also be called. What are the guarantees the C++ standard gives on the order of the calls to the copy constructors? Or, equivalently, this program is allowed to print? #include <iostream> class Z { public: Z() { std::cout << "Z" << std::endl; } }; class Y { public: Y() { std::cout << "Y" << std::endl; } }; class W { public: W(const char*) { std::cout << "W" << std::endl; } }; class X : public Z { public: X(const W&) { std::cout << "X" << std::endl; } private: Y y; }; int main(int, char*[]) { X x("x"); return 0; }

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  • why does array initialization in function other than main is temporary? [on hold]

    - by shafeeq
    This is the code in which i initialize array "turn[20]" in main as well as in function "checkCollisionOrFood()",the four values turn[0],turn[1],turn[2],turn[3] are initialized to zero in main function,rest are being intialized in "checkCollisionOrFood()".This is where fault starts.when i initialize turn[4]=0 in "checkCollisionOrFood()" and then access it anywhere,it remains 0 in any function,but! when i initialize next turn[] i.e turn[5],the value of turn[4] gets depleted .i.e turn[4] have garbage value.turn[20] is global variable,its index"head" is also global.I'm stuck.Plz help me get out of it.Ishall be highly obliged for this act of kindness.This is my excerpt of code unsigned short checkCollisionOrFood(){ head=(head+1)%20; if(turn[head-1]==0){ turn[head]=0; /this is where turn[] is iniliazized and if i access turn[head] here i.e just after iniliazition then it gives correct value but if i access its previous value means turn[head-1]then it gives garbage value/ rowHead=(rowHead+1)%8; if(!(address[colHead]&(1<<rowHead)))return 1; else if((address[colHead]&(1<<rowHead))&& (!((colHead==foody)&&(rowHead==foodx))))gameOver(); else return 0; } if(turn[head-1]==1){ turn[head]=1; colHead=(colHead+1)%8; if(!(address[colHead]&(1<<rowHead)))return 1; else if((address[colHead]&(1<<rowHead))&& (!((colHead==foody)&&(rowHead==foodx))))gameOver(); else return 0; } } void main(void) { turn[0]=0;turn[1]=0;turn[2]=0;turn[3]=0; /these values of turn[] are not changed irrespective of where they are accessed./ while (1) { if(checkCollisionOrFood()) { PORTB=(address[colHead] |=1<<rowHead); turnOffTail(); blink(); } else { PORTB=address[colHead]; createFood(); blink(); } } } Plz help me.

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  • NHibernate Pitfalls: Lazy Scalar Properties Must Be Auto

    - by Ricardo Peres
    This is part of a series of posts about NHibernate Pitfalls. See the entire collection here. NHibernate supports lazy properties not just for associations (many to one, one to one, one to many, many to many) but also for scalar properties. This allows, for example, only loading a potentially large BLOB or CLOB from the database if and when it is necessary, that is, when the property is actually accessed. In order for this to work, other than having to be declared virtual, the property can’t have an explicitly declared backing field, it must be an auto property: 1: public virtual String MyLongTextProperty 2: { 3: get; 4: set; 5: } 6:  7: public virtual Byte [] MyLongPictureProperty 8: { 9: get; 10: set; 11: } All lazy scalar properties are retrieved at the same time, when one of them is accessed.

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  • Creating a Lazy Sequence of Directory Descendants in C#

    My dear friend Craig Andera posted an implementation of a function that descends into a directory in a "lazy" manner, i.e. you get the first descendant back right away and not after all descendants have been calculated. His implementation was in Clojure, a Lisp variant that runs on the Java VM: (import [java.io File])(defn dir-descendants [dir]  (let [children (.listFiles (File. dir))]    (lazy-cat      (map (memfn getPath) (filter (memfn isFile) children))...Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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  • Stop lazy loading or skip loading a property in NHibernate? Proxy cannot be serialized through WCF

    - by HelloSam
    Consider I have a parent, child relationship class and mapping. I am using NHibernate to read the object from the database, and intended to use WCF to send the object across the wire. Goal For reading the parent object, I want to selectively, at different execution path, decide when I would want to load the child object. Because I don't want to read more than what I needed. Those partially loaded object must be able to sent through WCF. When I mean I don't load it, neither side will access such property. Problem When such partially loaded object is being sent through WCF, as those property is marked as [DataContract], it cannot be serialized as the property is lazy load proxy instead of real known type. What I want to archive, or solution that I can think of lazy=false or lazy=true doesn't work. Former will eagerly fetch all the relationships, latter will create a proxy. But I want nothing instead - a null would be the best. I don't need lazy load. I hope to get a null for those references that I don't want to fetch. A null, but not just a proxy. This will makes WCF happy, and waste less time to have a lazy-load proxy constructed. Like could I have a null proxy factory? -OR- Or making WCF ignoring those property that's a proxy instead of real. I tried the IDataContractSurrogate solution, but only parent is passed to GetObjectToSerialize, I never observe an proxy being passed through GetObjectToSerialize, leaving no chance to un-proxy it. Edit After reading the comments, more surfing on the Internet... It seems to me that DTO would shift major part of the computation to the server side. But for the project I am working on, 50% of time the client is "smarter" than the server and the server is more like a data store with validation and verification. Though I agree the server is not exactly dumb - I have to decide when to fetch the extra references already, and DTO will make this very explicit. Maybe I should just take the pain. I didn't know http://automapper.codeplex.com/ before, this motivates me a little more to take the pain. On the other hand, I found http://trentacular.com/2009/08/how-to-use-nhibernate-lazy-initializing-proxies-with-web-services-or-wcf/, which seems to be working with IDataContractSurrogate.GetObjectToSerialize.

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  • Array variable initialization error in Java

    - by trinity
    Hello I am trying to write a Java program that reads an input file consisting of URLs, extracts tokens from these, and keeps track of how many times each token appears in the file. I've written the following code: import java.io.*; import java.net.*; public class Main { static class Tokens { String name; int count; } public static void main(String[] args) { String url_str,host; String htokens[]; URL url; boolean found=false; Tokens t[]; int i,j,k; try { File f=new File("urlfile.txt"); FileReader fr=new FileReader(f); BufferedReader br=new BufferedReader(fr); while((url_str=br.readLine())!=null) { url=new URL(url_str); host=url.getHost(); htokens=host.split("\\.|\\-|\\_|\\~|[0-9]"); for(i=0;i<htokens.length;i++) { if(!htokens[i].isEmpty()) { for(j=0;j<t.length;j++) { if(htokens[i].equals(t[j].name)) { t[j].count++; found=true; } } if(!found) { k=t.length; t[k].name=htokens[i]; t[k].count=1; } } } System.out.println(t.length + "class tokens :"); for(i=0;i<t.length;i++) { System.out.println( "name :"+t[i].name+" frequency :"+t[i].count); } } br.close(); fr.close(); } catch(Exception e) { System.out.println(e); } } } But when I run it, it says: variable t not initialized.. What should I do to set it right?

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  • Basic C++ Speed (initialization vs adding) and comparison speed

    - by seld
    I was curious if anyone knows which of the following executes faster (I know this seems like a weird question but I'm trying to shave as much time and resources as possible off my program.) int i; i+=1; or int i; i=1; and I also was curious about which comparison is faster: //given some integer i // X is some constant i < X+1 or i<=X

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