head first j2ee

[J2ee spring] 15. Some Concepts in spring, j2ee15spring Dependency InjectionIn this case, in an Action or event, for example, if you want to write an Action, you need a pen, you used a new pen. You have an association with the pen. Without a pen, you cannot write any words. That is to say, your behavior depends on the pen, they constitute a dependency. Or if you want to assemble a computer (Transaction), you need a display, motherboard, mouse and ke

Interpretation Servlet of the J2EE 13 specification and j2ee13 interpretation servlet 　　What is Servlet? First, Servlet is a specification developed by Sun for server-side components. Second, the Servlet can run on the web server or application server. Third, servlets are managed by Servlet containers, such as "instantiate and manage Servlet objects" and "Call Servlet lifecycles ". To parse and encapsulate requests and responses to specific protocol

Implement j2eeaction in the background action of J2EE to control the front-end javascript pop-up dialog box 1. In the background Action: Request. setAttribute ("message", "this user name or password is incorrect. Please enter a new one! "); 2. Front-end jsp page: 2.1 Add the onload method to the 2.2 Add the js Code block to the jsp page as follows: Conclusion: The error message is put into the message in the background, and the js Code Execution d

When using eclipse for a project, select the latest version 3.0 in the bar. When the project is deployed, the error Tomcat version 6.0 only supports J2EE 1.2, 1.3, 1.4, and Java EE 5 Web modules occurs. Two solutions: 1. There is a file in the. setting folder of the Project, which configures various versions. Modify 2. Download Tomcat 7.0

Caused by: COM. bea. XML. xmlexception: weblogic. descriptor. beanalreadyexistsexception: bean already exists: "weblogic. j2EE. descriptor. servletmappingbeanimpl @ 8c7ef1f5 (/servletmappings [weblogic. descriptor. internal. compoundkey @ 8c4f6960])"At com. Bea. staxb. runtime. Internal. util. reflectionutils. invokemethod (reflectionutils. Java: 54)At com. Bea. staxb. runtime. Internal. runtimebindingtype $ beanruntimeproperty. setvalue (runtimebindi

RMI concept: to execute code on other machines through the network, traditional methods are not only difficult to learn, but also prone to errors. The best way to solve this problem is: Some objects are located on another machine. We can send a message and get the returned results, just like on our own machine. Java remote method call (RMI) enables programs running on the client to call objects on the remote server. The remote method call feature enables Java programmers to distribute operations

Web Container: provides an environment for the application components (JSP and Servlet) in the container, so that JSP and servlet can directly interact with the environment variable interfaces in the container, so that you do not have to pay attention to other system problems. It is mainly implemented by Web servers. For example, tomcat, WebLogic, and websphere. EJB container: provides various management functions for the component EJB running in it. As long as the EJB meeting the

J2EE hierarchical design is the most basic design concept for Java Enterprise applications. In the most common hierarchy, the system layers are as follows: Presentation Layer: displays the client. Service layer: services or functions provided directly to the client. It is also a function provided by the system. Domain Layer: domain activities in the system. Dao layer: data access objects, which operate databases through domain object. Some guiding pri

I recently learned the J2EE enterprise application testing practice book. I think I can still learn a lot. I uploaded the example in the last chapter to csdn to save it as a network hard disk address. The Java resource files used in this example can be downloaded online. The sample is developed using eclipse. If it is transferred to myeclipse, it seems that the JDK version error will be reported. You only need to modify it slightly. The following are

My application to the press last week was finally approved and the publishing contract was finalized. Spring 2: Principles and Practices of the Lightweight J2EE development framework is a book that explains spring design principles, I wrote several members of easyjf. Half completed in the early stage, and there is still one month before the submission time. During this time, I will devote myself to writing this book and developing cases. We will try t

J2EE has three development environments. 1. Entry level: jcreator + Tomcat + ant + SQL Server2. Application level: Eclipse + myeclipse + JBoss + MySql3. Enterprise Level: JBuilder + WebLogic + Oracle We generally use: myeclipse + Tomcat + MySqlThe first step must be after JDK is installed. Use cmd javac Java to test it .....Step 2 configure the JDK environment variables. Three environment variables must be configured:They arePath c: \ Program Files \

The J2EE framework is believed to be understandable to anyone who has used it ...... Spring: A good MVC framework, but generally only uses its IOC and AOPStruts: Common MVC FrameworkWebwork: the front-end interceptor is invincible.Hibernate: An ORM framework for data persistenceIbatis: An ORM framework for data persistenceDisplaytag: front-end display template. This box is not very mature yet and is not recommended. Of course, it will work after tran

J2EE--JDBC, jdbc JDBC (Java Data Base Connectivity, java database connection) is a Java API used to execute SQL statements. It can provide unified access to multiple relational databases, it consists of a group of classes and interfaces written in Java. To put it simply, JDBC can do three things: establish a connection with the database, send SQL statements, and process the results (similar to the sqlhelper class in the SQL server database we used pre

Java Web Listener, j2ee This article is in the study of the summary, welcome to reprint but please note the Source: http://blog.csdn.net/pistolove/article/details/44310967 A: The Listener defines the objects that are used to listen to and handle events or state changes on other objects. When the Monitored Objects change, they take corresponding actions immediately. The client requests the ServletContext --> Application context object. The Container c

J2EE Summary (III)-a deep understanding of the working principles of JSP development, j2eejspI. JSP and its working principles 1. JSP (assumerver page) Java Server page, which is similar to ASP in terms of name and is a technology written on the server. 2. technologies used to develop dynamic web pages Why can it be used to develop dynamic web pages? This is related to the technology used in writing. It uses HTML to define the structure of the page, b

J2EE -- Servlet, servletI. Servlet basics:Servlet is a server-side Java application independent of the operating system platform and network transmission protocol. It is used to expand server functions and generate dynamic Web pages. The maximum purpose is to expand server functions by dynamically responding to client requests. Servlet is not started from a command line, but loaded by a Web server containing a Java virtual machine.Ii. Working Principl

It is not surprising that there are dozens of rows of variable definitions in the game logic class. This is especially true for J2EE. To save memory space, many people leave the object-oriented feature to squeeze the Code together. The general situation is that my code drowned !! So I pay attention to this point when designing the structure, and always try to save the Code a little more scalability. It is not difficult to think about it. Just think ab

"> forwardname= "Showonlineuser"Path= "/showonlineuser.jsp"/> Action>Dynaactionform-Org.apache.struts.action.DynaActionFormWrite Actionform to write its Setter/getter method, simple actionform can use this to replace, it is actually a actionform sub-class, with map storage, configuration method as follows:In Struts-config.xml:Form-beans> Form-beanname= "LogonForm"type= "Org.apache.struts.action.DynaActionForm"> Form-propertyname= "username"type= "Java.lang.String"/> Fo

II. create a database and test the oracle8i (by the way, we can practice it) (for convenience, I simply abbreviated oracle8i to 8i). The 8i and 9i are indeed somewhat different, but there is little difference on the interface, let's take my oracle8i as an example! In practice, we first create a development user for ourselves and create a table !! Create a new J2EE instance in oracle 　　 II. create a databaseTest the oracle 8i (by the way, our trainer

Step 3: install and configure jBuilder7 here I installed weblogic to install jBuilder. do not install jBuilder to a directory with spaces, such as PrograihFiles or a Chinese Directory. otherwise, errors may occur during compilation. The installation is very simple and you don't have to talk about it. here, I will focus on the configuration tips. I think jBuilder may be slow to run, because jbuilder uses 32 J2EE by default. 　　 Step 3: install and con