init

Note: I'm relatively new to Objective-C and am coming from Java and PHP. Could someone explain to me why I always have to first allocate and then initialize an instance? Couldn't this be done in the init methods like this: + (MyClass*)init { MyClass *instance = [MyClass alloc]; [instance setFoo:@"bla"]; return instance; } + (MyClass*)initWithString:(NSString*)text { MyClass *instance = [MyClass init]; [instance setFoo:text]; return instance; } ... Is this just a relict from the old C days or is there something that I'm not seeing? I know this isn't a problem as I could as well always call

　　通常我们写js以及调用： function init(){ console.log("init") } function load(){ console.log("load") } init(); load(); 　 在页面的script标签对里定义两个function，然后执行一下函数名即可。如果我们还要定义一些变量，或者别的函数啥的 ，则继续按照语法往下写。久而久之，这个页面函数不计其数，分不清哪些函数是同属一个功能，哪些函数同属另一个功能，这样很明显不友好，我之前就在几千行的js中找某个功能的N个方法，大多在一块，个别不在，很难找，特费劲。 　　大概是出身后端的原因，对面向对象有一定的理解，后来知道javascript也可以面向对象编程，一些写法自然也就有所变化了~ 　　既然是面向对象编程，那么一切皆对象，我们就用对象这个点来阐述下面要讲到的面向对象编程。 　　什么是对象？=>万物皆对象。 　　对象的特征是什么=>具有一系列的属性和方法。 　　所以我们在进行面向对象编程的时候，重点看属性和方法。 　　javascript创建对象有三种方式，分别是字面量方式、函数方式、原型方式： //字面量方式 var obj1={ init:function(){ console.log("init1") } }; obj1.init(); //函数方式 var obj2

I want to write init method in swift , Here I given NSObject model class in Objective-C -(id)initWithNewsDictionary:(NSDictionary *)dictionary { self = [super init]; if (self) { self.title = dictionary[@"title"]; self.shortDescription = dictionary[@"description"]; self.newsDescription = dictionary[@"content:encoded"]; self.link = dictionary[@"link"]; self.pubDate = [self getDate:dictionary[@"pubDate"]]; } return self; } How can I write this method in swift ? that could be good bases for your class, I guess: class MyClass { // you may need to set the proper types in accordance with your

I'm begginer of python. I can't understand inheritance and __init__() . class Num: def __init__(self,num): self.n1 = num class Num2(Num): def show(self): print self.n1 mynumber = Num2(8) mynumber.show() RESULT: 8 This is OK. But I replace Num2 with class Num2(Num): def __init__(self,num): self.n2 = num*2 def show(self): print self.n1,self.n2 RESULT: Error. Num2 has no attribute "n1". In this case, how can Num2 access n1 ? In the first situation, Num2 is extending the class Num and since you are not redefining the special method named __init__() in Num2 , it gets inherited from Num . When a

I've tried to find a precise explanation of what the init() function does in Go. I read what Effective Go says but I was unsure if I understood fully what it said. The exact sentence I am unsure is the following: And finally means finally: init is called after all the variable declarations in the package have evaluated their initializers, and those are evaluated only after all the imported packages have been initialized. What does all the variable declarations in the package have evaluated their initializers mean? Does it mean if you declare "global" variables in a package and its files, init(

This question already has an answer here: What __init__ and self do on Python? 18 answers While reading the code of OpenStack and I encountered this. A class named 'Service' inherits the base class 'object', and then in Service's __init__() method, object's __init__ is called. The related code looks like this: the class definition: class Service(object): and Service's init method definition: def __init__(self, host, binary, topic, manager, report_interval=None, periodic_interval=None, *args, **kwargs): and a call to super(the 'object' here) in Service's init: super(Service, self).__init__(

下面谈谈我对Tomcat架构的理解 总体架构： 1、面向组件架构 2、基于JMX 3、事件侦听 1）面向组件架构 tomcat代码看似很庞大，但从结构上看却很清晰和简单，它主要由一堆组件组成，如Server、Service、Connector等，并基于JMX管理这些组件，另外实现以上接口的组件也实现了代表生存期的接口Lifecycle，使其组件履行固定的生存期，在其整个生存期的过程中通过事件侦听LifecycleEvent实现扩展。Tomcat的核心类图如下所示： 1、Catalina：与开始/关闭shell脚本交互的主类，因此如果要研究启动和关闭的过程，就从这个类开始看起。 2、Server：是整个Tomcat组件的容器，包含一个或多个Service。 3、Service：Service是包含Connector和Container的集合，Service用适当的Connector接收用户的请求，再发给相应的Container来处理。 4、Connector：实现某一协议的连接器，如默认的有实现HTTP、HTTPS、AJP协议的。 5、Container：可以理解为处理某类型请求的容器，处理的方式一般为把处理请求的处理器包装为Valve对象，并按一定顺序放入类型为Pipeline的管道里。Container有多种子类型：Engine、Host、Context和Wrapper

I want to define a constant that should be available in all of the submodules of a package. I've thought that the best place would be in in the __init__.py file of the root package. But I don't know how to do this. Suppose I have a few subpackages and each with several modules. How can I access that variable from these modules? Of course, if this is totally wrong, and there is a better alternative, I'd like to know it. Jason R. Coombs You should be able to put them in __init__.py . This is done all the time. mypackage/__init__.py : MY_CONSTANT = 42 mypackage/mymodule.py : from mypackage import