black horse logistics

temporarily sleeps for 3 seconds} catch (Interruptedexception e) {E.printstacktrace ();}Thread 2 again to apply for resource 1, at this time resource 1 has been occupied by thread 1 is not releasedSynchronized (LOCK1) {System.out.println ("Hello Dead-lock");}}}}}}Class MyThread1 implements Runnable {Private Boolean flag = true; Defining Flag bitspublic void Run () {int i = 0;while (This.flag) {System.out.println (Thread.CurrentThread (). GetName () + "run, I ="+ (i++));}}public void Stop () {Th

指令#importfunctionality is the same as # include, which copies the contents of the file to the location of the #import Directive#importis used to include the header file of the system.#import ""with #include "" is used to include header files in your project#importis an # include upgrade that automatically prevents file duplication2, Foundation: is the foundation framework3, @autoreleasepool is an object of memory management (learn)4, the Nslog:foundation framework provides a function for log out

= -; - + int*P1 = a, *P2 = b; - + Change (P1, p2); A atprintf"a=%d\nb=%d\n", *p1,*p2); - - return 0; - -}3, the common use of pointers to the scene:1) indirectly access the variables in the caller in the function:2) allow the function to have multiple return values;"Level Two pointer"1, Level Two pointers:If a pointer variable holds the address of another pointer variable, the pointer variable is a pointer variable that points to the pointer. Also for level two pointers;int*p=a;int

The inheritance mechanism in OC is single-inheritance, and a subclass can have only one parent classOC supports multilayer inheritance, a inherits Nsobject,b inheritance A which is called multi-layer inheritanceThe order of method calls in the inheritance system1. Find in your own class2, if not, go to the parent class to find3, if not in the parent class, go to the parent class4, if the parent class also does not have, it also looked up until the base class (NSObject) was found5, if NSObject di

@private: Private, only the object method in this class can access it directlyA member variable is defined in that class to be used in that class@protected: Protected: Can only be accessed directly in this class and subclass, no longer externally accessible@public: Public, everyone can use, in this class, sub-class, external can be accessed@package: Mainly used within the framework, within the framework equivalent to @protected, outside the frame equivalent to @private (understand)This class: A

Stacks: Local variables: Variables defined inside a method or functionSystem ManagementHeap: Dynamic Storage AreaGenerally by the program ape Management# # Reference countIf memory management is inappropriate1, no longer use objects are not recycled, memory leaks, resulting in program flash2, is being used object is released, wild pointer, access to the wild pointer will cause the program to crashARC Automatic Reference Counting Auto Reference countMRC Manual Reference Counting Manual reference

Local variables, member variables, and global variables1. Inside a method, you can define a local variable with the same name as the member variable.So within the scope of this local variable, he overrides the member variable.2, if the definition and member variables with the same name as local variables, but also (ˇ?ˇ) want to manipulate local variables;3, global variables, the entire file sharing, all methods shared;A method that modifies this global variable in other ways uses this global var

getinstance () { return s; } } 2, lazy type: It is the characteristics of the object is called when the method is initialized, which is also called the object's delay loading. For example: In the following complete code, the single class enters memory, and the object has notexists, the object is created only when the getinstance () method is called.The complete code is as follows: Class single { private static single s=null; Private single () {} public Static

parent class methodpublic void Alldraw (Quadrangle quadrangle) {Quadrangle.draw;} Quadrangle.alldraw (square); Quadrangle.alldraw (parallelogram);Inherit the parent class quadrangle to Suqare and parallelogram.It then uses the Quadrangle class format to format the array, then assigns the arguments of the child class object to the object of the parent class, and the draw () method for outputting each element with foreach.---------------------------------------------------------------------------

, servletexception {System.out.println ("Filterdemo1....before"); Chain.dofilter (request, response); System.out.println ("Filterdemo1....after");} Filter objects when they die, the aftermath works. public void Destroy () {}}Package Cn.itheima.filter;import Java.io.ioexception;import Javax.servlet.filter;import javax.servlet.FilterChain; Import Javax.servlet.filterconfig;import Javax.servlet.servletexception;import javax.servlet.ServletRequest; Import Javax.servlet.servletresponse;public class F

: After the () of the method.Attention:Don't throws if you can try...catch.However, at present lectures for convenience, I all throws.(5) What is the difference between a compile-time exception and a run-time anomaly?A: The compile-time exception must be processed.B: Runtime exceptions can be handled or not handled.(6) The difference between throws and throw?A:throwsLocation: After the method (), followed by the class name.If the following is based on RuntimeException and its subclasses, then th

establishment of a buffered character stream object, the existence of a stream object first.BufferedReader Unique method: public string ReadLine ();//read one line at a time, and return the character data before the row tag as a string when the row is marked. When the end is read, NULL is returned.BufferedWriter Unique method: Publicvoid newLine ();//write the platform-related line delimiter to mark the end of a line. The Windows platform is ' \ n '. Copyright NOTICE: This article for Bo Master

(SocketAddressendpoint) This socket to the server. Connect connect(SocketAddressendpoint, inttimeout) This socket to the server and specify a timeout value. getInetAddress() Returns the address of the socket connection. getLocalAddress() Gets the local address of the socket binding. getPort() Returns the remote port that this socket is connected to. isClosed() returns the closed state of the socket. isConnected() Returns the connection state of the socket. toString() Convert this socket to

bufr = new BufferedReader (new InputStreamReader (system.in)); String line = null;while (line = Bufr.readline ())!=null) {byte[] buf = line.getbytes ();D atagrampacket dp = new Datagrampack ET (Buf,buf.length,inetaddress.getbyname ("192.168.3.4"), 10103);d S.send (DP), if ("over". Equals (line)) { SYSTEM.OUT.PRINTLN ("Chat program exit"); Break;}} Ds.close ();} catch (Exception e) {System.out.println (e.tostring ());}}} Class Rece implements Runnable{datagramsocket DS; Rece (Datagramsocket ds

Object wrapper class new featuresThe new feature in the JDK1.5 version is that objects can be directly operated between values. As follows:4// 直接将4赋值给整型对象x，称为自动装箱，等同new Integer(4)2//直接运算，x + 2自动拆箱，然后再将和自动装箱，并赋值给xnew2//x = x + 2的具体过程。Integeris int more than one value null . There are some of the following features:128128127127;System.out.println(m == n);System.out.println(a == b);The result is as follows, because when the value of integer is within the range of byte, if the value already exists

constructors. In the class, constructor getdeclaredconstructor (class... C) can independently obtain the private constructor. 　　　　 Run the constructor: Object newinstance (object... O) in the constructor class) If setaccessible (Boolean 0) in the accessible class of the parent class of the constructor class is true, the JVM access check is canceled during the runtime to run the private constructor. In the class, object newinstance () can directly obtain and run the constructor of the public-mod

--- Java training, Android training, IOS training, and. Net training. We look forward to communicating with you! --- Design two classes and write out the set get method corresponding to the attribute (write method only) 1> Vehicle (1) attributes * Number of wheels * Speed (2) Method * Set and get methods corresponding to the attribute The Code is as follows: 1 // setter getter Declaration 2-(void) setwheels: (INT) wheels; 3-(INT) wheels; 1 // setter getter implementation 2-(void) setwheels; (INT

--- Java training, Android training, IOS training, and. Net training. We look forward to communicating with you! --- 1. Basic concepts of Scope Local variables and global variables have their own scopes, and member variables are no exception. Scope: the scope within which access is allowed. 2. Scope type of member variables @ Public can be directly accessed anywhere @ Protected can be accessed directly in the implementation of the current class and subclass @ implementation. Only the set get met

No.: Notes downloading black horse programmer _ watch video notes _ 1-10 Concept:. netAnd C # L. Net/DOTNET: generally refers to the. NET Framework framework, a platform and a technology. L c # (C sharp): a programming language that can be used to develop applications based on the. NET platform. L (*) Java: A technology and a programming language C sharp indicates sharp. c ++ indicates two well numbers (#)

is usually used to close resources. Finally is not executed in only one case. When it is executed to system. Exit (0); fianlly will not execute. Three formats of the processing statement: First format: // Remember: Catch is used to handle exceptions. If no catch is found, the exception has not been processed. If the exception is detected. It must be declared. Exceptions are embodied in child parent class overwrite; 1. When a subclass overwrites the parent class, if the method of the parent