We have learned about 3 directions in Java, first, desktop system, including C / S structure; second, J2ME, facing unlimited field, very potential guy, see China's mobile phone users know. Third, the platform for enterprise applications, calculated, J2EE. In the first time, I feel that Java entry doesn't seem to be C, C is getting started. Tools do not have Turbo C, Visual C is easy to use (own machine, you can't afford JBuilder, greedy guy, you must pack it later) . What Java_Home, ClassPath, virtual machines and other concepts are the initial basis, and the people next to them rarely use Java. I feel that Java is doing applet. I am incredible is that new names such as Java 2, JDK, J2SE, J2EE, J2ME are spread in their minds. Slowly knowing that JCP organization is an origin of the Java-related specification http://java.jcp.org, so I subscribe to a list of mailing. It's a good thing, regularly have the latest trends in Java, so Java's dynamics have a full view, I suggest you go to subscribe. Free. After you do it yourself, you don't understand Java (TM) 2 SDK Documentation, you don't understand, especially if you don't need any manual. There is a copy. After taking the Java development environment, remember to edit and compile with UltraEdit (in which the Java compiler) can be used. Slowly use JCREATOR. Nice, at least many aspects have improved. I started to sell a set of 2 books, it is not bad. It is enough for entry. I don't know when it is, I have to start the project. I used to see what I saw in the book. I have a good opportunity to work in the project. I have a feeling slowly. I started using Swing, developing a desktop. The system is placed, and it is not possible to put a button, and then I know there is a layout manager. Start relating to database access, JDBC.
Every time, after the beautiful meal, I also feel that I should have a way of learning, because this is not very good. Comparison. Let me think of Java Specification, right, I started researching the Java specification. The most beginning download specification is JDBC Specification, a lot of concepts, especially Database's transactional control, and you have a more in-depth understanding of her understanding. For the development of C / S structures, such as Swing JDBC, develop database applications, let me learn to develop two-story application. Very nice. I don't know when I want to start developing a website, based on Linux JSP JavaBean Oracle system. It is very interesting. Why do you say this? Because there is different from Swing JDBC development mode, there are more layers between the system (JavaBean, just this! Hey); After completing the project, you have a better understanding of many aspects of Java. Start thinking about a question, what is J2EE? . We have learned about 3 directions in Java, first, desktop system, including C / S structure; second, J2ME, facing unlimited field, very potential guy, see China's mobile phone users know. Third, the platform for enterprise applications, calculated, J2EE. After the painful choice, I chose J2EE .. Share J2EE to bring me happiness. Learning now, the biggest feeling is: Simple is beautiful, beauty is Java. There will be no pain in learning MFC, and there will be no hardships of STL, and the network application is not inferior to C . Start entering my J2EE trip.
Still downloaded a J2EE specification, a J2EE SDK. Started research J2EE, it is about 1 month, starting to feel, just at this time, I need me to complete a J2EE architecture project. Almost the same is completed, many concepts are not very clear after writing, because things are too much, mainly based on the JSP (Servlet) Session Bean EIS architecture development system. Of course, many things have been learned, at least in writing of SB EJBs. Know how JSP calls EJB ...... After completing the project, I started to study the Java Pet Store, very enjoyable. Start knowing the Servlet filter, XML aspects, knows the practical application of various technologies in the entire framework of J2EE. Slowly, start studying WebLogic Configuring PET Store (also SUN). Slowly analyze the difference between the two. I have a good feeling of J2EE Specification. Because J2EE Specification itself is very serious, the PET Store gives a vitality. In the repeated study, I understand 70-80% of the J2EE architecture. The new problem came out again, how will the actual enterprise construct a J2EE system? With this problem, I started analyzing Core J2ee Patterns, this book. At the same time, there is also EJB Design Patterns. Slowly, began to know the charm of J2EE, know why J2EE will get better recognition in the enterprise. Everyone knows that the design pattern is the word, in the company, will your boss look at your code? Will you appreciate your DP? I think very little. After completing your progress, overtime, overtime, work hard, I think you don't have more time to analyze research DP. But the J2EE framework is different, she has a lot of excellent design patterns, we are design and developing, The architecture has used a lot of design patterns in a J2EE system. For example, the DAO design pattern packaged in MVC and EJB. The frame J2E system is not too difficult to use Session Fa? ADE, Message Fade design mode. This is also the place where J2EE attracts me. I know slowly, as a J2EE developer, we have to master the core content. I personally think that 3 is important. Implement EJB systems commonly used architecture, design patterns, such as Session Fa? ADE, Message Fade, DTO, etc. The common mode in the J2EE system architecture. UML-> EJB, EJB-> UML maps. It is also the same in research.
Be good at enjoying lonely, but fortunately there is J2EE! On the Internet, the bookstore provides a lot of information, many ways can get J2EE information. How to system, efficient learning J2EE this problem is in front of us. For example, some people don't know how to start after reading a lot of books. Waiting for these issues is our most difficult. How do I find a good way? In fact, in order to see a point of view, such as learning English, a total of three levels, first is the vocabulary, then the syntax, then the habitual usage (I hope the reader can consider the problem from the perspective of programming, see these two What is similar to what they logically, they are the same. For example, on the mathematics class, the teacher is in the blackboard, everyone is very easy to understand, there will be many problems when you do it. These seem simple questions, in fact, it contains a truth: theoretical connection is actual, theoretical guidance practice. Our theory is that we have a good way. Some people have seen a lot of books, wrote a lot of procedures, and the level is still very slow, it is difficult to cross this difficult relationship. Or method problem. Of course, the method I talk about is your own experience, experience, everyone has its own unique way. There is no absolute good, absolutely bad way, see who is the object. So here we focus on the way I will mention in this article. Everyone comment comments. J2EE is now done. We know that J2EE consists of many technologies, such as EJB, XML, JDBC, RMI, JSP, servlet ,. . . . Wait these, but also contain a lot of content. Regardless of how these specific technologies develop, how can we change, we have to grasp the main line, that is, master the essence of the J2EE architecture. What to analyze it, the role object is nature is J2EE Specification (the latest version is 1.4, http://java.sun.com/j2ee)! Of course, the premise of learning J2EE is that you have enough familiar with J2SE, there is a little, you have a good attitude and interest. Just look at the J2EE specification is not enough, it is best to think about the products and examples, I suggest that you use JBuilder 7 Bea Weblogc Platform 7.0, this development mode. Why do you say this? First, the functionality of JBuilder 7 itself is good and should belong to the mainstream java IDE. Second, Bea WebLogic Platform 7.0 has a good level of J2EE Specification's latest support, and it is also easier to get, and people use more. Third, the development efficiency is good. (Borland website has a document that is developed by JBuilder 7 Bea WebLogic 7.0. PDF format.)
JBuilder 7 itself provides a lot of help documents, there is a PDF format, and HTML format (using Javahelp technology), and some bookstores have some JBuilder's reference books. Personally think that there is no need, first, the version is more old; second No content; third, generally plagiarized the help documentation provided by JBuilder itself. (Personal view, no commercial purposes). Of course, your foreign language is almost the level of four levels. This can not be no, at least reading is good (in fact, I am also afraid, but after starting, the English data is also very simple, and very authentic! Also improve your foreign language). With these two, we need to find the right object to learn. It will give you a reference here. First, this place in JBuilder 7 installation directory, ~~: / jbuilder7 / samples / ejb / ejb20 / eSITEWL, has a good example, esite. Among them, the Session Fa? ADE design mode is used, and techniques such as JSP, Servlet, Session Beans, Entity Beans (CMP) are used. You can refer to the second. That is, the second, http://java.sun.com/j2ee/tutorial/index.html provides J2EE TUTORIAL data provided by SUN. Third, Java PET Store, just started learning J2EE technology to analyze this example is a bit difficult, and then the J2EE architecture in this example is not very practical, but she gives us almost all core technologies of J2EE, and also provides a book Design Enterprise Applications with J2EE Platform, very good. Fourth, it is recommended to understand the J2EE architecture. After the EJB, XML, JSP, SERVET and other technologies have better understanding and program experience, it is recommended to see these books. "J2EE In Practice", "Core J2EE Patterns", "Sun Certified ENT Architect for J2EE - Tech Study Guide", "Java Tools for Extreme Programming - wiley", "EJB Design Patterns", "MasteringEJB 2", "Enterprise JavaBeans, 3rd ", you can see :). With the above foundation, combined with some experience in the project, I think there will be a lot of improvement. After prelimating the above-mentioned basis, each of us can have its own position in J2EE. For example, some developers can consider spending time spending the business logic layer, others like Huafu in a representation, more greedy guys All layers in J2EE. There is also the focus of Web Services (J2EE 1.4 Specification, estimated to launch in early 2003, future important development direction). At the same time, everyone should pay attention to the system design, implementation, and recommendation to use together !!! as required by TOGETHER !!! Requirements to UML. Article source from Chinaitlab
