Getting Started with Lambda Expressions in Java 8

Lambda Expressions are introduced in Java 8 and is the most prominent feature in this release of Java. This blog is a tutorial of Lambda Expression which will take you through all the details. At the end, you will be able to kick start using Lambda Expressions in your day to day programs.

What is Lambda Expression ?

Lambda expressions are expressions that aims to reduce writing clumsy code. Lambda expressions do not do technically anything new that couldn't be done before Java 8. Lambda expressions has following syntax :

(parameter1, parameter2 ...)                   ->                      (statements or expressions)
                                    (First Part)                 (Second Part)               (Third Part)

First Part      : Input parameters containing variables that will be used in Third part.
Second Part  : This is called as Arrow Token (A hyphen followed by right angle bracket)
Third Part     : Code statements to be executed

☺Don't worry if you don't get much out of above syntax. It's very easy and will be much clearer as we move ahead.

Comments

Post a Comment

Popular posts from this blog

Why do I get Error: could not open `C:\Program Files\Java\jre7\lib\i386\jvm.cfg

In this post, I will take a problem solution approach. Problem: While executing a jar from command line or while executing a java command to run any program, following error get displayed. "Error: could not open `C:\Program Files\Java\jre7\lib\i386\jvm.cfg" Solution 1: Check the PATH environment variable. Make sure, it consist of path to bin directory of your Java JDK installation. Example path upto bin :  C:\Program Files\Java\jdk1.7.0_71\bin If the variable is not as above, do change it appropriately. If you don't know how to change the value, please refer this post. Make sure you restart your command prompt after you newly set the variable. Otherwise, changes will not come in effect. Solution 2: While doing Java installation, following 3 files get copied to  C:\Windows\System32 java.exe javaw.exe javaws.exe Check if this is the case by opening the folder. If yes, delete these files . These files are from jre distribution but as we need files
Read more

Preparing applications for migration to Oracle 11G from Oracle 10G

This post will guide you through few hidden facts involved in doing migration from Oracle 10G to Oracle - 11.2.0.4 . Oracle has made significant changes related to performance improvement in 11G release.However, there is no change from perspective of SQL constructs i.e. the effect of SQL queries is same on Oracle 11G. The best way to know about new changes in any Oracle release is to follow its "Companion document" . For Oracle 11G migration, the companion document can be found here . So at a high level, steps for preparing your applications ready for migration are - Read the Companion document and know what new changes are there in the release. If you find any change that could probably impacts the application (i.e. either SQL construct change or a performance change) in Step-1 above, then identify if you can take any of following measures -  Do nothing ( Sometimes, even if there is a change in release it doesn't impacts the application behavior. This can be c
Read more

Getting started with Weblogic Maven Plugin

Image
What is Weblogic Maven Plugin ? Weblogic Maven Plugin is a plugin (just a single jar) that comes bundled with Weblogic Application Server which helps to manage the Weblogic server through Maven commands. When I say manage, I mean following actions on Weblogic server - Create/Modify/Delete weblogic domain Start server/Stop server/Restart server Deploy/Undeploy applications Yes. You read it correctly. Just similar like "tomcat7-maven-plugin" which is to run tomcat within maven, we now have "weblogic-maven-plugin". This means, you can run weblogic server in background during maven builds. So, let's gets started with using weblogic-maven-plugin. Installing the weblogic-maven-plugin For this tutorial, my machine setup is as follows: Weblogic Server Version                      :12.2.1 (can be downloaded from here ) Weblogic Server Installation directory : D:\Oracle_home\ OS                                                         : Window
Read more