A Lambda Expression is a representation of an anonymous function which can be passed around as a parameter thus achieving behavior parameterization. A lambda consists of a list of parameters, a body, a return type and a list of exceptions which can be thrown. I.e. it is very much a function, just anonymous.

An instance of a lambda can be assigned to any functional interface 
 whose single abstract method’s definition matches the definition of the lambda. In fact, a lambda is a less verbose way of defining an instance of an interface provided the interface is functional. Since, the definition of a lambda can match the definition of multiple functional interfaces, hence, a lambda instance can be assigned to any of these matching interfaces.

The reason i picked this topic was because it was something new i have seen in the java language. Also wanted to know more about it and see if i can utilized it on some of my java programming language.

Examples of lambda expression.

First of all. Comparing java 7 to java 8.

public interface StateChangeListener {

public void onStateChange(State oldState, State newState);

}

In java 7 we implement this interface in order to listen for state changes. You do this

public class StateOwner {

public void addStateListener(StateChangeListener listener) { … }

}

But in java 8 you can add an event listener using a java lambda expression. like this.

StateOwner stateOwner = new StateOwner();

stateOwner.addStateListener(

(oldState, newState) -> System.out.println(“State changed”)

);

 

From this topic ( lambda expressions), i learned that previous java or java 7, if i wanted a block of code to be executed, we need to create an object and pass the object around. From Java 8, lambda expressions enable us to treat functionality as method argument and pass a block of code around. Lambda expressions in Java 8 are very powerful and therefore very compelling. For me, lambda expressions is way much better, convenient and very easy.

link to the resource : http://tutorials.jenkov.com/java/lambda-expressions.html

 

From the blog CS@worcester – Site Title by Derek Odame and used with permission of the author. All other rights reserved by the author.

https://www.thecodingdelight.com/write-clean-code/#ftoc-heading-2

As I learn more about computer science, I find that writing code for a programming project is very similar to writing an essay for an English project. I find that the core structure of a coding language mimics the core structure of any other language. A run on sentence can be compared to poorly using indentations, grouping your variables together at the top of the page is like having a well organized thesis statement. Just as we spend years taking English courses perfecting our grammar and sentence structure, it takes a lot of practice and learning to perfect our syntax and ability to write clean code.

Some benefits of writing clean code include:

• Being able to easily follow your own code to track down errors
• More efficient productivity
• A more professional reputation
• Your employer/teacher will resist the urge to strangle you

This article explains in detail why we should try to better our code and how to develop better habits from common mistakes. I for one, typically write messy code just hoping it will work and later try to buff out bad variable names, overly complicated methods, and half written comments. After reading this article however, I’ve learned tips and tricks for writing better code and how to embrace the clean code mindset. I can only imagine how many frustrated programming teachers’ evenings I’ve saved after reading this article, so for your own sake and for the sake of whoever has to look at your code, I recommend you read this article as well.

From the blog CS@Worcester – CS Mikes Way by CSmikesway and used with permission of the author. All other rights reserved by the author.