Yogesh's Tech Blog

Recently out product has adapted JDK 7 for development as well as run-time. So get familiar everybody in the team with the new features of JDK , so i prepared a presentation "Getting started with Java 7". Sharing same presentation to refer you haven't still adapted JDK7.  Presentation:

Auto-Edit Strategy This post of Everything About Editor series explains about editors auto complete feature. Auto edit feature of any editor helps developer while writing code, for example in java editor of eclipse provides auto complete features for string quotes , open braces etc. When you type open curly braces ‘{‘ , eclipse java editor auto inserts closing curly braces considering line and indentation. Here I am going to implement auto-edit strategy for open single , double quotes and opening curly braces ‘{‘. To use auto edits, you must implement the org.eclipse.jface.text.IAutoEditStrategy interface, which contains just one method: void customizeDocumentCommand(IDocument document,DocumentCommand command); This is called each time you make a change to the document with the DocumentCommand object containing the information about that change. So, adding indents or making any change to the text being changed is as simple as modifying the DocumentCommand object. 1. Implement IA...

  Auto-boxing is introduced in JDK 5.0.  it converts primitive data variable to corresponding wrapper classes and vice versa without any explicit efforts. For example int to Integer and Integer to int . Here is the one program using auto-boxing feature 1: class AutoBoxingTest 2: { 3: public static void main(String[] args) 4: { 5: boolean b1= true , b2= true ; 6: System.out.println(" boolean Result = "+ compare(b1,b2)+" \n "); 7: System.out.println(" Int Result = "+ compare(10,10)+" \n "); 8: System.out.println(" String Result = "+ compare(" ABC "," ABCE ")+" \n "); 9: System.out.println(" float Result = "+ compare(10.00f,10f)+" \n "); 10: System.out.println(" Mixed Result = "+ compare(10l,10l)+" \n "); 11: System.out.println(" Mixed[long,int...

What is XML Oriented programming ? – In this approach every application have one or set of documents associated with it. This xml documents contain application configuration information which are defines application’s run time behavior. It is very easy to maintain frequently changing configurations setting using xml document. What is Annotation Oriented Programming ? – Annotation oriented programming language leverage active code generation with the use of declaration tags embedded within the application source code to generate any other kind of source code, configuration files etc. XML vs Annotation 1. XML duplicates a lot of information like class, method name etc. But annotation are part of class it self so no duplication of information. For example web.xml <servlet> <servlet-name> DemoServlet </servlet-name> <servlet-class> demo.servlet.DemoServlet </servlet-class> </servlet> <servlet-map...

Auto-Boxing/Unboxing is introduced in Java 5 version. It supports automatic conversion of primitive type (int, boolean, float, double) to their equivalent Objects ( Integer, Boolean, Float, Double) in assignment , method and constructor invocation and other way also. Here is the examples Auto-Boxing Integer i = 10; // Auto-boxing converts primitive int value to Integer Object Auto-Unboxing int i = 0; i= new Integre(10); // Auto-Unboxing converts Integer Object to primitive int There is serious problem with using Auto-bocing/Unboxing, it may result null pointer exception. Take an example of following program package testproject; public class TestAutoUnboxing { private static TestAutoUnboxing test= new TestAutoUnboxing(); //cause Null Pointer Exception public static final Boolean YES = true; // Autoboxing for private boolean amIHappy = YES; // Instance Variable public static void main(String[] args){ System.o...