class cluster In a class cluster, only an abstract superclass is public. Allocating an instance actually creates an object of a private subclass. As such, subclassing always happens on an abstract class and requires all methods to be implemented. See…

Primitive Method "When it comes to subclassing, knowing which methods are ‘primitive’ methods is important. The notion of primitive methods are those methods form the basis of the public interface/class. The rest of the methods are just convenience m…

[Accessor Search Implementation Details] Key-value coding attempts to use accessor methods to get and set values, before resorting to directly accessing the instance variable. Key-value coding 优先使用accessor methods走获取与设置数据,之后再使直接访问instance variable. […

本人菜鸟,在学习Log4j 2 的时候做的一些笔记---对"官方网站"的翻译,部分内容自己也不懂,希望大家指点 Garbage collection pauses are a common cause of latency spikes and for many systems significant effort is spent on controlling these pauses.(垃圾收集暂停是导致延迟尖峰的一个常见原因,许多系统的重要的工作都是花在控制这些暂停上.) Man…

2017年5月3日15:06:15 这个是英文翻译版,我看过作者的文档其实不太友善或者不方便阅读,不如wiki方便 后面补充一些,结构性文档翻译 这是一部官方网站文档,剩余大部分都是开发的时候和网络总结来的 项目官网:https://tcpdf.org/ github:https://github.com/tecnickcom/TCPDF 都没比较完整的api文档,所以最后的demo需要总去总结,好吧 (发现所有例子全部翻译消耗时间过于长,只把其中不同的部分分离出来,也方便读者使用) 2018年…

按照一定规则使用匹配模式在目标空间进行搜索,然后执行相应操作: 运行时系统将kvc的运行机制解释为模式匹配,将值的兼容性问题解释为装包解包问题 一.模式匹配 The default implementation of the NSKeyValueCoding protocol provided by NSObject maps key-based accessor calls to an object’s underlying properties using a clearly defined…

We can create subclass within a class cluster that defines a class that embeds within it an object. These class objects are composite objects. So you might be wondering what's a class cluster. So we will first see what's a class cluster. Class Cluste…

Part I:equals() (javadoc) must define an equivalence relation (it must be reflexive, symmetric, and transitive). In addition, it must be consistent (if the objects are not modified, then it must keep returning the same value). Furthermore, o.equals(n…

1. Primitive Types        Any data types the compiler directly supports are called primitive types.        Primitive types map directly to types existing in the Framework Class Library (FCL).        For the types that are compliant with the Common La…

blog.sunnyxx.com 我是前言 学习objc时,尤其是先学过其他编程语言再来看objc时,总会对objc的类声明的关键字interface感到有点奇怪,在其它面向对象的语言中通常由class关键字来表示,而interface在java中表示的却大约相当于objc的protocol,这个关键字的区别究竟代表了objc语言的设计者怎样的思想呢,在objc类设计中需要注意哪些问题呢?接下来对这个问题进行一些思考和探究. interface? 先来段Wiki: In object-orien…

4.Operator Overload Methods allow a type to define how operators should manipulate instances of the type. 1.The CLR doesn’t know anything about operator overloading because it doesn’t even know what an operator is. programming language defines what e…

1.Programming Language Primitive Types primitive types:Any data types the compiler directly supports. Primitive types map directly to types existing in the Framework Class Library (FCL). use the FCL type names and completely avoid the primitive type…

转:https://github.com/kimziv/PinYin4Objc 最好用的汉字转拼音代码PinYin4Objc(PinYin4J的objc版本)(更新到v1.1.1,增加block异步处理) 2013-10-08,更新到 V1.1, add async methods whit block, solve ui blcoking problems and fix some cache bugs; 1. -(void)cacheObjec:(id<NSCoding>)obj forK…

A small coding test that I encountered today. Question Using only primitive types, implement a fixed-size hash map that associates string keys with arbitrary data object references (you don't need to copy the object). Your data structure should be op…

referee:Java Programming Tutorial Advanced Input & Output (I/O) JDK 1.4+ introduced the so-called New I/O int java.nio package and its auxiliary packages to support high performance and intensive I/O operations. NIO is meant to complement the existin…

什么是回调? 因为它是从C开始进入编程世界.术语改只是口.叫习惯了.java里通常叫listener(监听器).C/C++里通常叫callback(回调),ObjC里面叫delegate(托付) 回调就是调用事先设置一个上下文数据(它可能是某个消息值,可能是某个函数.可能是某个对象)到某个负责处理数据的对象或者代码里. 然后開始运行这个处理过程,这个处理过程处理完了之后.会依据处理的结果将之前设置的相应的上下文数据反馈给你. 举个样例吧.比方我有个函数是下载一个http的图片资源. 在调用这个函…

我们知道在mac或iphone上编程最终逃不开os x平台,你无法在windows或linux上开发纯正的apple程序.(so不要舍不得银子买mac啦)虽说linux和windows上有移植的obj-c编译器,但是平台开发框架还是在mac上啊.比如cocoa框架包括Foundation框架,Application Kit框架和Core Data的第三方框架;二cocoa Touch指的则是Foundation,Core Data以及UIKit框架.对于Foundation框架中各个类的使用,可…

说实在的,写这第5篇的时候十分纠结,代码老是不能动态绑定,在编译时就会出错,最后发现这是开了ARC的原因.开了ARC obj-c就不能动态绑定了吗?这个问题还不清楚哦.把ARC关闭后,虽然会有警告,但运行是正确的.下面上代码: #import <Foundation/Foundation.h> @interface A:NSObject{ double i; } @property double i; -(double)mul:(double)x; -(void)show; @end @imp…

Class Data or Attributes state of the application Methods or Functions have behavior Namespace is a container for related classes Assembly (DLL or EXE) is a container for related namespaces is a file which can either be a EXE or  a DLL Application in…

One can explicitly write @objc on any Swift declaration that can be expressed in Objective-C. @objc相关的参量只能修饰类.类的成员.扩展以及只能被类实现的协议: 下面开列修饰的情况和说明 一.无修饰 NSObject-derived classes no longer infer @objc A declaration within an NSObject-derived class will no…

In a previous post Should I expose asynchronous wrappers for synchronous methods?, I discussed "async over sync," the notion of using synchronous functionality asynchronously and the benefits that doing so may or may not yield. The other directi…

Primitive Data Types (The Java™ Tutorials > Learning the Java Language > Language Basics) https://docs.oracle.com/javase/tutorial/java/nutsandbolts/datatypes.html « Previous • Trail • Next » The Java Tutorials have been written for JDK 8. Examples a…

Objective-C Compiler Directives @dynamic "You use the @dynamic keyword to tell the compiler that you will fulfill the API contract implied by a property either by providing method implementations directly or at runtime using other mechanisms such as…

Some Objective-C APIs—like target-action—accept method or property names as parameters, then use those names to dynamically call or access the methods or properties. In Swift, you use the #selector and #keyPath expressions to represent those method o…

User-Mode Constructs The CLR guarantees that reads and writes to variables of the following data types are atomic: Boolean, Char, (S)Byte, (U)Int16, (U)Int32, (U)IntPtr, Single, and reference types. This means that all bytes within that variable are…

[objc explain]: Non-fragile ivars   (2009-01-27 09:30 PM)   Non-fragile instance variables are a headline feature of the modern Objective-C runtime available on iPhone and 64-bit Mac. They provide framework developers more flexibility without losing…

转载自这里. 最近看了一本书——iOS6 programming Pushing the Limits(亚马逊有中文版),最后一章是关于Deep ObjC的,主要内容是ObjC的runtime.虽然之前看过runtime的programming guide,但读之乏味也不知道能用在何处.现在有点小小的理解,觉得别有乾坤,索性把runtime的相关东西给整理一下. 下面就从官方文档开始,看看runtime有哪些特性,以及各自的应用场合. 基本概念 对于现在绝大多数的64位操作系统而言,我们接触到的…

在Objective-C中,消息是通过objc_msgSend()这个runtime方法及相近的方法来实现的.这个方法需要一个target,selector,还有一些参数.理论上来说,编译器只是把消息分发变成objc_msgSend来执行.比如下面这两行代码是等价的. 1 [array insertObject:foo atIndex:5]; 2 objc_msgSend(array, @selector(insertObject:atIndex:), foo, 5); class的方法列表其实…

本文转载至 http://blog.csdn.net/c395565746c/article/details/7573793   当对象经过在dealloc方法处理时,该对象就已经处于已销毁状态,其它对该对象发任何消息都会报错   视图对象的创建.alloc..可以发生在其它线程.   「initWithNibName: bundle:」载入nib档案来初始化 「loadView」载入视图 「viewDidLoad」在载入视图至内存后会呼叫的方法 「viewDidUnload」在视图从内存中释放…

Objective-C entry points https://github.com/apple/swift-evolution/blob/master/proposals/0160-objc-inference.md Before Swift 4, the compiler made some Swift declarations automatically available to Objective-C. For example, if one subclassed from NSObj…