thinking recursively with java

All +All- Thinking in Java 1. introducation to object + - object-oriented -- abstraction 1. You can regard all the conceptual components of the problem to be solved as an object. 2. Program is a group of objects that send messages to each other and tell the other party what to do. A message is a request that calls a method specific to an object. 3.

reference array that holds a reference to each element object.2.3 GCNo programmer is required to voluntarily free up memory.class 2.4 class keyword. Default: The member variables of the base type in the class, and if not initialized, they will be initialized to 0 (PAN), but the local variable is uninitialized but will error in the compile phase. 2.5 method parameter return valueReturnType methodName (/**/ ) {/* */} 2.6 Java Progr

thinking in Groovy the first chapter simplifies Java code with groovy Author: Chszs, reprint should be indicated. Blog home: Http://blog.csdn.net/chszs 1. Groovy's installation is currently in the latest version of Groovy is 2.1.2 version, download address: http://groovy.codehaus.org/DownloadAfter downloading, unzip groovy-binary-2.1.2.zip to a directory, and then set the GROOVY_HOME environment variable t

compile and run time, and a Java1.1 unique "reflection" mechanism that allows you to find class information independently at run time. First we discuss the rtti of "tradition" and then discuss the reflection problem. Our known Rtti forms include: (1) Classic styling, such as "(Shape)", which uses RTTI to ensure the correctness of the modelling and creates a classcastexception violation after encountering a failed shape. (2) A class object that represents the object type. You can query the clas

function) (in the method area)Not in heap memory, objects can be shared.Can be called by the class name. (class name. static member).Characteristics of static statics:1. Load as the class loads. 2. Shared by the object being used. 3. Precedence over object existence. 4. Can be called by the class name. 5. Static variables can use the GET, set methodUnique data with member variables, multiple objects that share data with static variables.13. Instance variable and class variable (static) differen

correctly");} try {targetshape= (Shape) oneclass.newinstance ()} catch (Exception e) {//TODO auto-generated catch Blocke.printstacktrace (); System.out.println ("instance not created correctly");} return targetshape;}Call:public static void Main (string[] args) {String targetclassname=classnameconfig.getproperty ("Shape.classname"); System.out.println ("Targetclassname:" +targetclassname); Shapefactory shapefactory=new shapefactory (); Shape Targetshape=shapefactory.getshape (targetclassname);

[Thinking in Java] modifier public, protected, default, private, thinkingprotected When using Java, four modifiers, public, protected, default (no modifier), and private, are often encountered. The differences between them are written here. Public: any access outside the package Protected: any access in the package, only sub-class access outside the package Defau

assignment, two arrays point to the same block (the address of the array), the elements in the array are changed with one of the array names, and the elements of the array that the other array names point to change.2) The assignment of array in C language is the assignment between two different regions (different array addresses), and it is not possible to assign values to arrays by connecting the array names directly with an equal sign, assigning the elements within the array to one another. (

Horse soldiers teach Note the point:there is no absolute right or wrong in design. Over design is also a sin No actual design is going to one step beginners do not consider too many principles and rules, the most important thing is to write abstract classes and Interfaces enjoy the fun of OO First of all talk about the idea of this thing, thought is a strategic height of things, tools are tactical height of things, tools of learning: Dare to use and diligent use.The second is the simple desc

is invalidated.Flota (float) can be understood as the standard layer entangled, the content of the non-floating box in the standard layer will be affected by the floating box, and the non-floating box itself will see the floating box completely does not exist, to replace its position. (floating can break the flow of the document and not break the text stream).Floating position: the upper and lower position is affected by the height of the box in the standard flow,The left and right positions ar

and return values are transmitted over the network.Soap vs. JMS:1) SOAP focuses on remote service invocation, and JMS focuses on information exchange.2) In most cases soap is a direct interaction between two systems (Consumer Of course, JMS can also implement Request-response mode of communication, as long as the consumer or producer one side of the broker.3) In most cases, WS is synchronous and JMS is asynchronous. Although WS can also be asynchronous, JMS can also be synchronous.Reference Doc

transformation . In the process of upward transformation, the only thing that can happen in the class interface is the Lost method. Because it is converted from a more specialized type to a generic type, it is always safe.7.7.2 re-discussion on combination and inheritanceIn object-oriented programming, there is a sentence called "Combinatorial better than inheritance", although inheritance is emphasized many times, it does not mean to use inheritance as much as possible. One of the clearest way

Put yourself in the process of learning Java problems encountered in the list, write their own various periods of the idea of the problem, until the final resolution, should be to persist in learning this thing has been promoted. See the Java Foundation Chapter, there is a piece of code to write the private Point Center (P65), what is point, ah, this position should not be a data type? The re

excuse to lazy instead of trying to improve themselves, it will tell you: Hey, anyway, you do not do anything in this regard or do not bother to blindly toss. I can give you advice one is, take your eyes off of yourself, spend time on learning Java, and firmly tell yourself that someday this book will look like a children's books. Recommendation two, what you really like, be sure to really try to think about giving up, otherwise you will regr

Thinking in Java notes (1 ~ 10) 1. Data Type testing Class A {public int I; Public double D; public float F; public long l; Public Boolean B; Public char C; Public short S; Public byte ;} public class classtest {public static void main (string ARGs []) {A = new A (); system. out. println (". I = "+. i); system. out. println (". D = "+. d); system. out. println (". B = "+. b); system. out. println (". by =

":" And sorts the string by number. The Code is as follows: Public static void main (string [] ARGs) { Thinking process: The first method should be thought of first, storing data using arrays and then sorting using various sorting methods. In fact, the key of this question is not just sorting, but establishing association with another key point, that is, the one-to-one correspondence between set a (random number) and Set B (serial number. Therefore,

6 access Rights control6.1 Package: library Unit Package, import, import *, import static; Modify the CLASSPATH environment variable to add your own class library to the environment variable and import it in any Java program; 6.2 Java access rights modifier Access Rights:public>protected> Package access (no qualifier) >private; Public: any class accessible anywhere; Defaul

() method2.Hashtable: As previously mentioned, the main Hashtable are very similar to HashMap.Try to use HashMap (there are still a lot of other options when multithreading is synchronized)3.BisSet: Bitset is a good choice if you want to efficiently store large amounts of "on/off" information. But its efficiency is only for the space. Given the need for efficient access time, bitset is slightly slower than the local array, and the Bitset minimum capacity is long:64 bit, if the contents are smal

I learned to build Javadoc when I first learned the Java language, but it was only built with the Windows command line. Read the Javadoc here to know the new found in fact, we do the project to use some comments, but did not use eclipse to generate this document, through the review, eventually complete the knowledge. First, the code in the book: Second, Eclipse generates Javadoc documents in the following three ways:1, right-click in the project list,

{Private intNum,x;Private int[] A=New int[4];Private int[] vis=New int[4]; Public void DFS(intCurintT1,intT2) {if(num!=-1)return;if(cur==4){if(t1*t2==x) {num=t1; }return; } for(intI=0;i4; i++) {if(cur==0a[i]==0)Continue;if(cur==2a[i]==0)Continue;if(vis[i]==1)Continue; vis[i]=1;if(cur1) DFS (cur+1, t1*Ten+A[I],T2);if(cur>=2) DFS (cur+1, t1,t2*Ten+a[i]); vis[i]=0;if(num!=-1)return; } } Public void Init(intx) {num=-1; This. x=x;/// Java