Thursday, February 26, 2009

Spring framework 3.0 M2 Released

Hi,

At last Spring framework 3.0 M2 released . It has certain features such as JPA 2.0 support ,and MVC portlet 2.0 etc .

Here is the link

http://www.springsource.com/download

Saturday, February 21, 2009

Constructor dependency injection vs setter dependency injection

Hi ,

As per dependency injection we are having 2 popluar dependency injections as setter dependecy injection,constructor dependency injection.

setter dependency injection: In this injection we will inject everything as setter methods.
for example setEmpName(). etc .

constructor injection: In this injection we will inject everthing as constructor . for example we are having class Employee . then Employee(Arguments) construction can intialize itself .


Now which one is good ? It dependens on appliation. But i prefer constructor injection. Reason is constructor injection follows order , means there is very less number of chances for ambigity .

Let us assume that we are having 3 classes or beans with in our appliaction .

for ex : Employee ,dept ,school

so 3 of them are having same method name as "Name" describing as Employee name,dept name,school name etc..

so when ever you are applying setter injection as setName() there is chance for container to go wrong to different bean as cyclic error often some times.

but when ever you are using or calling constructor injection u have to call Employee(),dept(),school() respectively. one more point is it will follow order ,if it fails it throws error.

for example you are having certain classes like

y1 y=new y1();
k1 k =new k1(y);

through our constructor injection

H h=new H(y,k); // Here if it fails in any no of arguments code willn't compile at all .

Happy Sivarathri bye :_)

OSGI Technology

Hi ,

OSGI is technology which is popular now adays . a brief explanation is here

Problem : Suppose let us assume we have n number of war files in a application. Assume that we installed our application in application server . Rememeber we made single war or jar with multiple jars/wars and deployed as single component. suppose any change we want to do for one jar file in whole application. Then we have to stop the whole application and make the changes and deploy again . which is effectiing all the modules of application.


Solution: Here is OSGI technology comes for that ,it comes with bundles of components and if u want to change the particular jar u can change at runtime also with out stopping appliaction .This is a simple example use of OSGI.

Now OSGI is coming with almost all popular application servers.

Here is the link

http://www.osgi.org/Main/HomePage

Thursday, February 12, 2009

web Authorization using XACML

Hi ,

  as per servlets specification we can have security access to web reources in  containers in xml file.But if u want to have security access  customized like  some of employeees only allowed to certain parts u can have XACML , where 2 points will be there  to control resources ,first reuest  will come to  policy enforce pont (PEP) frrom there it will check policy decision point PDP ,whether access needed or not , instead of writing customizes code for ur application. u can use jboss XACML
thing .

Here is link





Java FX 1.1

Hi,

 java FX 1.1 released in which u can develop applications not only related to desktop, u can have ur applications in even mobile also


Sunday, February 1, 2009

java Performance Test clues

Hi ,
As i read in one article about java performance test .Here are some clues which i got from article.
When ever u are doing performance testing for java code make sure following points
1) As per Performace test use what are exisitng poplular java performance tools .
2) when ever u are doing performance testing on LOOPS like While,for,Iterator you should nt get variant results. If it is

2.1 Repeat the performance tests for particular code ,and make sure results are same.
2.2 Before doing testing make sure that all applications are closed like word etc ,because if your jvm using any bit of application results will vary.
2.3 Check your memory available in CPU .
2.4 Check the threads which are dependent on other threads.

3) At last check all the methods or application code which is contacting outside application .

These are some clues i found , you please refer certain performance tools available in market .

WEB4J framework

Hi,

  A new framework for java  WEB4J came to Exisistance.If  you want to try this new framework
check here