drawing methods of graphics class in java

The following is a simple example of invoking a known method through the reflection mechanism of Java Packagecom.togeek.mvntest;Importjava.lang.reflect.InvocationTargetException;ImportJava.lang.reflect.Method;/** * @authorTogeek using Reflection to call methods * @addresshttp://www.cnblogs.com/togeek/* @Date: November 29, 2015 18:01:31*/ Public classreftest {@SuppressWarnings ("Unchecked") Public Static

When a class inherits from another class, the subclass does not have a method of the parent class. When you invoke a method with an object of a subclass, it is first found in the subclass, and if there are no changes in the subclass, look in the parent class.When a method is defined only in the parent class, the proper

1. The domain variables defined in the class can be accessed by all methods in the class.2. The scope of formal parameters and defined local variables is limited to the method, and local variables must be initialized before they are used.3. If the local variable has the same name as the domain variable in the class, th

(thread.currentthread (). hashcode () + "get:begin" + sdf.format (new Date ())); try { Thread.Sleep (5000); // } catch (Exception e) { } finally { System.out.println (thread.currentthread (). hashcode () + "get:end" + Sdf.format (new Date ())); Read.unlock (); } return 1; } } } Two threads are read threads and the results are as follows22474382 Get:begin 2011-04-16 18:26:134699264 Get:begin 2011-04-16 18:26:1322474382 get:end 2011-04-16 18:26:184699264

Package com.kk.innerClass;/*** Interfaces are implemented through internal classes* Solve the problem of duplicate methods in multiple interfaces**/Interface Machine {void run ();}Class Person {void Run () {System.out.println ("person start");}}public class Android extends person {Private class Machineheart implements

Methods for obtaining file names, class names, method names, and row numbers in Java ?? In C, macroFILE,LINEIn Java, you can use the StackTraceElement class to obtain the file name, class name, method name, and row number. The Co

Code Public classTest { Public Static voidMain (string[] args) {shape shape=NewCircle (); System.out.println (Shape.name); Shape.printtype (); Shape.printname (); }} classShape { PublicString name = "Shape"; PublicShape () {System.out.println ("Shape Constructor"); } Public voidPrinttype () {System.out.println ("This is shape"); } Public Static voidPrintname () {System.out.println ("Shape"); }} classCircleextendsShape { PublicString name = "Circle"; PublicCir

believe it, try it; In our code, it is normal to call the method of the subclass of the generic class. The biggest drawback of this method is that every time we add a data class to be parsed, we need to add a subclass of this generic class. The advantage is that this subclass does not need to write any code, because the logic is implemented in the gener

; - } - + Public voidsetName (String name) { - This. name=name; + } A PublicString GetName () { at returnname; - } - -}1 Packagecom.ning;2 3 ImportJava.util.*;4 5 Public classDemo05 {6 7 Public Static voidMain (string[] args) {8SetNewHashset//creating a Set Collection Object9Set.add (NewPeople ("Heart Grow Fonder", 10010));//adding elements to the collectionTenSet.add (NewPeople ("Xiao Li", 10011)); OneSet.add (NewPeople ("Xiao Zhao", 1001

The system class is often used to obtain the system's attribute data. Common methods of Packagecom.yuanzijian01;importjava.util.arrays;/**system class:* publicstaticnativevoidarraycopy (objectsrc,int srcpos, Objectdest,intdestPos, int Length);src- source Array srcPos- Start position dest- destination array in source array length- The number of array elemen

Servlet The Java Servlet development tool (JSDK) provides a number of packages that need to be used when writing a servlet. These include two basic packages for all Servlet: Javax.servlet and Javax.servlet.http. Java Servlet Development tools can be downloaded from Sun Company's web site. The following describes the HTTP servlet application programming interfaces provided by Javax.servlet.http. The HTTP Ser

to delete from child to parentFile delete1 =NewFile ("H:\\test\\b.txt"); Delete1.delete (); File Delete2=NewFile ("H:\\test"); Delete2.delete (); //Rename function: Public boolean renameto (File dest)//if the path name is the same, it is renamed. //file rename1 = new file ("H:\\demo\\a.txt"); //file rename2 = new file ("H:\\demo\\b.txt"); //Rename1.renameto (rename2);//Change the a.txt of the H:\\demo path to B.txt.//if the path name is different, it is renamed and clipped

0x01In the Java Math class there are three methods for floating-point numbers to take integers, namely ceil (rounding up) floor (rounded down) roundthree methods0x02 ceil upward rounding, after rounding is always larger than the original number.System. out. println (Math.ceil (2.34)); System. out. println (Math.ceil (-2.34));3.0-2.00x03 floor is rounded down and

Here are a few ways to round decimal values to integers: Math.ceil (), Math.floor (), and Math.Round (). These three methods follow the following rounding rules: math.ceil () performs an upward rounding, that is, it always rounds the value up to the nearest integer; math.floor () performs a downward rounding, that is, it always rounds the value down to the nearest integer; Math.Round () performs a standard rounding, that is, it always rounds a n

Part of the Codepublic void Go (servletrequest request,servletresponse response) { String methodName = "index";//Method name string ClassName = "indexaction";//class name try{ class　　Java reflection creates a class with constructed parameters and executes

Download Java interview book:Http://download.csdn.net/source/3563084 Set and list are two sub-interfaces of collection. The elements in set must be unique. Therefore, the equals method must be rewritten. For the hashset method, the hashcode method must be rewritten. When an element is added to a hahset, It is not added to determine whether the element already exists. Therefore, the comparison between the two instance objects is involved. To compare t

1 Packagearrays class;2 3 Importjava.util.Arrays;4 5 Public classTestarrays {6 Public Static voidMain (string[] args) {7 int[] a={1,9,3,5,7,8,2,6,0,4};8System.out.println (Arrays.binarysearch (A, 9));//-119 Arrays.sort (a);TenSystem.out.println (Arrays.binarysearch (A, 9));//9 One int[] b=New int[9]; AArrays.fill (b, 8); -System.out.println (arrays.tostring (b));//[8, 8, 8, 8, 8, 8, 8, 8, 8] - } the}View CodeCommon

corresponding characters in the both strings are equal ignoring Case. Characters C1 and C2 are considered the same ignoring Case ifAt least one of the following istrue: The characters is the same (as compared by the==operator) Applying the method Character.touppercase (Char) to each character produces the same resultapplying the method Character.tolowercase (Char) to each character produces the same resultparameters:anotherstring-The String to compare ThisString againstreturns:true ifThe argume

When creating a class,If the variable is initialized, then there will be an initial value.For example:Handler Mhandler =NewHandler () { Public voidhandlemessage (Message msg) {selectordialog.cancel (); if(Msg.what = = 1) {newslist= (list) Msg.obj; Listviewadapter=NewMainlistviewadapter (newsmainactivity. This, newslist); Listview.setadapter (Listviewadapter); } Else if(Msg.what = =-1) {uihelper.toastmessage (newsmainactivity. This, "No Data

The example in this article describes how Java uses the preference class to save the last record. Share to everyone for your reference. The specific analysis is as follows: When using Java JFileChooser to select files, we always want to be able to save the last recorded record when we open the next time, that is, when we open the File dialog box, we can always t