java 8 in action

users to assigning only ' M ' or ' f ' values to it. By setting sex to private and then using Setsex () to set the gender, you can control this behavior completely. And you can control only get cannot set, or vice versa, but if it is public it will not. There's a little bit of a property. We may not want other users to write about our properties, which can be done directly without writing the Setx method. This is the read-only attribute. 3 coding normative we are in the design class, or a

Before doing some website projects, most of them are home is login, directly into the homepage of not much, also did not notice, today just notice to remember. It's kind of a little trick.But the problem with this is that if your home page data is from the database (although the data is either cached or static for large sites), then you definitely want to call action directly.This kind of writing certainly is not good, certainly will have 404.There ar

actioncontext.getapplication return to Map actioncontext.getapplication (). Get (Key) Equivalent to Servletcontext.getattributeActioncontext.getapplication (). put (Key,value) level in Servletcontext.setattribute* The Servlet object was manipulated using Actioncontext, but the servlet API was not used* For example: destroying session objects, adding cookies cannot be done by Actioncontext2. Direct access to SERVLETAPI (Scheme one interface injection)Servletcontextawarevoid Setservletcontext (Ja

DAO is mainly a number of interfaces, which define some of the methods used to delete and change the nameDaoimpl is the concrete implementation of DAOService Ibid, also some interfaces, mainly used to invoke the DAO layer of some methods, so the method defined here generally defines the parameters;Serviceimp a specific implementation of the service, here are some ways to invoke DAOThe servlet invokes the service to invoke its method, doing some operationsJSP view display and input dataThe DAO l

First, Java objects are stored in the heap of memory when they are created.The initialization of a class member is performed when the object is created before the constructor initialization object is called.Package com.test.createsort;public class Createobjectsort {public static void Main (string[] args) {Test T = new Test ("Testest");System.out.println (t);}}Class test{Private String name;//class member privately, method publicPrivate String name2 =

(); Bb.test (); }}　　Look at the bold section above, name this variable is a private variable defined inside the Tagbean. This variable provides unconditional access to the SYSTEM.OUT.PRINTLN (name) in the inner class;3. Multiple inheritance can be achievedis one of the most important reasons why an internal class exists. It is because of his existence that the inheritance mechanism of Java is more perfect. We all know that

A few days ago wrote a Java 8 in 2019 to stop free of charge to the enterprise to provide updated articles, in an attempt to force users to a new generation of Java version upgrade, but unfortunately, the small part of today received the Oracle Java version of the upgrade push, Loaded is actually

First, briefFile file class, mainly related to the operation of files. Commonly used file operations are: the creation of files (folders), the deletion of files (folders), the file read and download (copy) and so on;Ii. creation and deletion of files (clips)1. Create a Process instance://Create a new File@Test Public voidTestcreatefile () {File m=NewFile ("E://file");//Create a folder//determine if the folder exists no if(!m.exists ()) {M.mkdir ();//Create a folder} File F=NewFile ("E://f

1. In the background action:Request.setattribute ("message", "This user name or password is wrong, please re-enter!") ");2, the front page JSP:2.1. Add the OnLoad method to the 2.2, add the JS code block in this JSP page, as follows:Summary: The JS Code Pop-up dialog is executed through the research onload method in the foreground JSP by putting the error message into the message in the background.Implement Java EE in the background

freely during the program's operation.The core part of the actual overall policy pattern is the use of abstract classes or interfaces, and the use of policy patterns can be very small and fast to modify when users need to change.There is a certain similarity between the strategy mode and the factory model. The tactical weapon is relatively simple and easy to understand, and can be switched freely at run time, while the Factory mode is primarily used to create objects.　　The strategy mode is suit

); ADatavalidation.setshowpromptbox (true); at Firstsheet.addvalidationdata (datavalidation); - -Bytearrayoutputstream out=NewBytearrayoutputstream (); - Workbook.write (out); - byte[] contents=Out.tobytearray (); -InputStream newinputstream=NewBytearrayinputstream (contents); in returnNewinputstream; -}Requirements Description: Excel first page first column drop-down menu data is displayed on the second pageIf you delete one item on the second page, save the data in th

Sometimes we need to monitor the mouse and keyboard movements (mouse movement, keyboard click), such as key record, mouse coordinate record.We use JNA to achieve the above operation tips:jna class Library uses a very small local class library sub dynamic call to Local code Java interface local code The structure of the method and some basic properties. This saves a lot of configuration and compilation code to fit multiple platforms. This is becaus

-driven Pojo Jmstemplate effect: Eliminate lengthy and repetitive JMS code, create connections, get sessions, and send and receive messages, allowing developers to focus on building messages to be sent or processing received messages, capturing subclass-check exceptions for thrown jmsexception exceptions, and re-throws the subclass of the corresponding JMSException exception non-check type exception. Message-driven bean (Message-driven bean,mdb): You do not have to proactively view

The previous article on the architecture has been done, now using the interactive program. As set out in the diagram: Create a Java program, switch to MyEclipse view, build under SRC. Code: 1　package　com.duduli.li; 2 3　public　 class　Input　{ 4　　　　　public　String　display(String　 name,String　sex,String　email){ 5　　　　　　　　　 System.out.println("your　name　is　"　+　name); 6　　 　　　　　　　System.out.println("your　sex　is　"　+　 sex); 7　　　　　　　　　System.out.println("yo

1. Action return string (logical view name)If local * If local 2. Configuration Default Type property value Dispatcher* Request.setattribute (Name,value);* Request.getRequestDispatcher.forward ();* name= "redirectaction" and Name= "redirect" differ in configurationStruts2 page Layout supports JSP, Freemarker, Velocity and other technologiesIn enterprise development, STRUTS2 provides good AJAX support, defining the result set type= "JSON"3. Use forward

Web developers often need to use the JavaScript pop-up dialog box to give users some informational hints, including the following types Reading Table of Contents dialog box type Test page Code for the Selenium Action dialog box dialog box type 1. Warning Boxes: Validation results, errors or warnings for prompting user related information 2. Hint box: Used to prompt the user to enter data in the current dialog box, generally requ

the above operation:is readable () return from select () are readable () return from select () is readable () return from select () is readable () RET Urn from select ()Then comment out the Sks.remove (key) line and run it again:is readable () return from select () return from select () return from select () the From select () return from select () retu RN from select () return from select () return from select () return from select () return from select () return from select () Return from sel

Excel book protection is very common, mainly do not want to let others modify Excel when used. This avoids malicious modification of data and increases the credibility of the data.Here is a Java POI for setting book Protection:You can use the Protectsheet (password) method of the Hssfsheet class. The specific code is as follows: PackageCom.util;ImportJava.io.FileOutputStream;ImportOrg.apache.poi.hssf.usermodel.HSSFCell;ImportOrg.apache.poi.hssf.usermo

*@returnValue*/ Public Staticstring Getcookievaluebyname (HttpServletRequest request, string name) {MapReadcookiemap (Request); if(Cookiemap.containskey (name)) {String Cookievalue=(String) cookiemap.get (name); returnCookievalue; } Else { return NULL; } }}Used in the controller of Spring MVC:Using the Cookievalue annotation map request parameter in spring MVC, @CookieValue has three properties, as follows: The parameter name of the value request argument; Require

public class Parent {public void init () {System.out.println ("1 init Parent"); This.demo ();} public void Demo () {System.out.println ("2 demo parent");}}public class Son extends the Parent {public void init () {super.init (); System.out.println ("3 init son"); This.demo ();} public void Demo () {System.out.println ("4 demo Son");} public static void Main (string[] args) {//Current run class Sonson son = new son (); Son.init (); Init (son)}}The output is:1 init parent4 demo son3 init sonWhen m