New Mda-based J2ee Framework

Now time in Java field, the efficiency of program and running performance is the most important criterion to evaluate Java frames,but they are always ambivalent.It's a hard job to give a nice choice between them. And Even any one of them can also not be evaluated properly,especially running performance. We cann't reach conclusion that a frame is perfect for our single test,Becauce different results may be concluded from the test on great systems engineering or on a small application.So we have to adjust our frame more agilely. In the text, as the problem of running performance layed aside,we shall try to make the program more effective.The efficiency of program depends on the structure of the code. In Java field ,'coupling decomposed'is used to describe a rational frame.In the text, we name our frame DCO ,it means to be a coupling decomposed frame.Now many frames have give us metheds to decompose coupling.And Loc,DI and AOP has be used to show how to do it. we shall also give out our methed,but differing from them,we have some other mean in the text:1. decompose the relation between the code;2. decompose the relation between business logic and code.We shall use a model named 'method joined' which depend on IoC to decompose coupling.And we also bring a 'type-depended' MDA model to decompose the relation between the logic business and the code.'method-join' is a IoC method to give the control authority to the container. Unlike DI,it doesn't depend on the object.If a method's result has the same type as another method's parameter,we can join them up by the frame.MDA is not the traditional MDA in the text.To our MDA,data becomes the Model and code will be the driver.The type-depended MDA uses the key word 'type' to implement the PIM,and also uses data model to implement the PSM.differing from the static UML in the traditional MDA,the'data model'in DCO is a dynamic model.We can also save them to the database in order to make the code more agile.DCO also bring another function named'data conversion'.We don't expect users to think about the real data type(the data type in the Java code or the data type in the database),we provide a abstract type to replace them.And we also provide'data conversion'to turn the abstract type to the real data type.As a result,the ture data type would be transparent to users.Finally DCO applys itself to make the code reused in order to make more components.we name the process'compotents to be separated and joined'.Like the phenomenon of rolling a snowball,now we need to do nothing but setting when we have got a large number of components.A new J2EE frame must bring us a new coding method.This projectd can decompose the easy part and the difficult part in coding.To some programmers,coding become harder,but other component designers will find a easy way to design components. More components piled up,more easy and relax would be the coding job.