thinking recursively with java

returned to calculate) >, , | |,! (Short circuit: When the value of an expression can be accurately obtained in a certain judgment, the remainder of the expression is not executed, such as a| | b, if A is true, it can be judged that the entire expression is true and expression B will not execute) Direct constants: Float (f/f), double (d/d), Long (l/l), Hex (0x), octal (0), floating point (1.1e-5f) Bitwise operators:, |, ^, ~, =, |=, ^= Shift Operations:>>, Ternary operator: Boolea

) + (1*2^3) = 13, abstract out the mathematical expression as follows:n is the number on the X-bit (the default is from low to high), the corresponding decimal number on each of the common expressions is n*2^x, and the final sum is the answer Bitwise AND, if one of the two is 0 then 0 otherwise 1, example:1101 (Decimal)0110 6 (Decimal)Bitwise AND for 00100 4 (Decimal)| Bitwise OR, if two input bits are 0 The case will produce a 0, example:1101 (Decimal)0110 6 (Decimal)Bitwise OR for 1111 (decima

(although the private member is hidden and inaccessible), but more importantly it replicates the interface of the base class. In other words, all messages that can be sent to the base class object can also be sent to the exported class object. Because the type of message sent to a class is a known type, all means that the exported class has the same type as the base class.There are two ways to make a difference between a base class and an exported class: 1. Add a method directly in the export c

DoublegetNum1 () {returnNUM1; } Public DoublegetNum2 () {returnnum2; } Public voidSETNUM1 (DoubleNUM1) { This. NUM1 =NUM1; } Public voidSETNUM2 (Doublenum2) { This. num2 =num2; } Public Static DoubleGetResult () {DoubleResult =0; returnresult; }}//class that computes addition inherits from the calculated classclassOperationaddextendsoperationtest{ Public Static DoubleGetResult () {returnnum1+num2; }}//classes that compute subtraction inherit from a calculated cla

"Toast" + ID + ":" + Status;}} /** * Toast Queue * * @author Lenovo * */class Toastqueue extends linkedblockingqueuePackage Org.rui.thread.block2;import Java.io.ioexception;import Java.io.pipedreader;import java.io.PipedWriter; Import Java.util.random;import Java.util.concurrent.executorservice;import Java.util.concurrent.executors;import java.util.concurrent.timeunit;/** * tasks using pipelines for input, output * * @author Lenovo * */class Sender implements Runnable {private Rand Om rand = ne

1 //: Testeof.java2 PackageC10;3 4 ImportJava.io.FileInputStream;5 ImportJava.io.InputStreamReader;6 7 /**8 * @time: Morning 9:55:409 * @date: April 30, 2017Ten * @auther: Skyfffire One * @version: v0.1 A */ - Public classtesteof { - Public Static voidMain (string[] args) { the Try { -String path = "./src/c10/testeof.java"; -String encoding = "UTF-8"; - +InputStreamReader ISR =NewInputStreamReader ( - NewFileInputStream (path), encoding); +

I ran every example, the whole book was sketched, for the second time to generalize the focus to the cloud notes, I have been carefully read. Do not miss a point of doubt. Even if I can't understand the sentence (the stale translation), I'll fold it up so that I can sweep it two times. To tell the truth, it is still very fulfilling to read.ButReview: Like a nightmare!The generic parts of terror, painful examples, stale Chinese translations, lengthy descriptions.It was really painful, the generic

PrivateRabbittemplate rabbittemplate; Public void SendCall(String content) { for(inti =1; I 3; i++) {LongExpiration = i * the; String message = i +"-"+ content; System. out.println(String. Format("Sender:%s", message)); Rabbittemplate.Convertandsend(Mqconstant.Delay_call_ttl, (Object) message,New Expirationmessagepostprocessor(expiration)); } }}Server:@Componentpublic class Server { @Async @RabbitHandler @RabbitListener(queues = MQConstant.CALL) public void callProcess(String

There are a pair of rabbits, starting from the 3rd month after birth a pair of rabbits every month,Rabbit long to the third month after the birth of a pair of rabbits each month, if the rabbit is not dead, ask the total number of rabbits each month? Public classItem { Public Static voidMain (string[] args) {//The problem of the undead rabbitSystem. out. println (Rabbit (3)); } Public Static intRabbitintm) {if(M 0) {System. out. println ("input Error! No this month"); return-1; } E

. Concurrentlinkedqueue is an appropriate choice when multiple threads share access to a common collection. This queue does not allow the use of NULL elements. Linkedblockingqueue An arbitrarily scoped blocking queue based on the linked node. This queue sorts elements by FIFO (first-in, in-out). The head of the queue is the longest element in the queue. The tail of the queue is the element with the shortest time in the queue. The new element is inserted at the end of the queue, and

() {}}Panax Notoginseng - classEImp2Implementse{ the Public voidg () {} + classEGImplementse.g{ Public voidf () {}} A } the + Public Static voidMain (string[] args) { -A a=NewA (); $ $ //The type A.D is not visible - //A.D ad=a.getd (); - the //Type Mismatch:cannot convert from A.D to A.DIMP2 - //a.dimp2 di2=a.getd ();Wuyi theA.DIMP2 di2=(A.DIMP2) a.getd (); -System.out.println (Di2.getclass (). GetName ());//tes

1 PackageThinkingdemo;2 /*3 * 4 * About nested class coverage issues5 * 6 */7 classEGG2 {8 protected classyolk{9 Publicyolk () {TenSystem.out.println ("Egg2.yolk ()"); One } A Public voidf () { -System.out.println ("Egg2.yolk.f ()"); - } the } - PrivateYolk y =Newyolk (); - PublicEgg2 () { -System.out.println ("New Egg2 ()"); + } - Public voidinsertyolk (Yolk yy) { +y =yy; A } at Public voidg () { - y.f (); - } - } - cl

Pre-defined ClassLoader and parental delegation mechanismsNBSP;JVM predefined three types of ClassLoader: startup (Bootstrap) class loader: is a class loader implemented with native code that is responsible for Thinking about the Java class loading parent delegation mechanism (with an interview question)

I've been using environment variables before but have never thought about why?Java:Java_home = E:\Study\Java\JDK7.0In Path, set the%java_home%lib; java_home\ BinFinally, do not add;Principle: Internal words do is the concatenation of strings,So you can also write this directly:Java_home = E:\Study\Java\JDK7.0\bin; E:\Study\Java\JDK7.0\lib So at the end of path

the weights by reading the configuration file. Then, the front end is using the Bootstrap progress bar component.ConclusionMany times, we are thinking about how convenient, how to do easy, who do not know, these seemingly convenient components are actually a double-edged sword, although we use, the function also realized, but its principle you still do not know, you can only rely on his components. So, in the use of these open source components, we a

cases in which member initialization is initiated:(1) The basic member variable in a class: assigns it directly to the defined place. (not available in C + +)(2) Non-basic types of objects:Class Depth{}public class Measurement {Depth d = new Depth ();}(3) by invoking a method to provide the initial value, this method can also have parameters, but these parameters must be the occasional initialization:Public CALSS Methodinit2{int i = f (); int j = g (i); int f () {return 11;} int g (int n) {retu

, SecurityException, ClassNotFoundException, Illegalaccessexception, IllegalArgumentException, invocationtargetexception {//Dynamic get class String str= " Com.qianfeng.domain.Person "; Class Claz = Class.forName (str); Method m = Claz.getmethod ("meth", null); M.invoke (null,null);} Get the method with parameters and execute private static void AccessMethod1 () throws ClassNotFoundException, Nosuchmethodexception, securityexcept Ion, Instantiationexception, Illegalaccessexception, Ill

Constructor initializationInitialization sequence See P965.8 Array InitializationThe base type is initialized to 0Variable parameter list (can be represented by an array)5.9 Enum TypesThe sixth Chapter access rights controlHow to separate the things that change from the things that remain unchanged6.1 Package: library Unit6.2 Java access modifier words6.3 Interfaces and implementationsAccess rights for Class 6.4Seventh re-use classTwo ways to reuse c

: the two structures are manifested in polymorphism, which means that whether it is an upward transformation into an interface or an abstract class, there is no effect on polymorphism.Two. The difference between an abstract class and an interface.Although interfaces and abstract classes look very similar, there are a number of different points between them.(1). Abstract classes are still classes, so declare them with the class keyword and then use the extends keyword to inherit. The interface is

Class classes and Object objects are core object-oriented concepts. A class is a description of a kind of thing, an abstract, conceptual definition. An object is an entity that actually exists for that kind of thing. This is also known as an instance. Java uses classes to describe things, and defining classes is actually defining members and variables in a class that includes Properties: member variables in the corresponding class field= proper