Java 8 Optional examples and usage

        Why Optional : Use it with streams , use it in your return types, make your code safer against to the NPE, make your code more readable...This allows the caller to continue a chain of fluent method calls.

And Note: The key here is the focus on use as a return type. The class is definitively not intended for use as a property of a Java Bean. Witness to this is that Optional does not implement Serializable, which is generally necessary for widespread use as a property of an object.

If you really wonder what will change in your life with this new Stolen keyword (from Guava) you'd better to read its origin.

More code & less bullshit.. Lets see its usage then..

And you can use in streams as follows

Java 8 Lambda Building Blocks: Predicate, Function, Consumer, Supplier, BinaryOperator

Let the code explain itself..Be quiet...And read..










Bye

Java 8 Lambda Expressions

I'll try to explain the topic according to my motto --"No bullshit , Just Code.."

1) SAM= Single Abstract Method = An Interface with Only One Method = Functional Interface

2) A class with a method which will consume a lambda expression

3) Now.. Actionnn...Lambda expression as a parameter





Okeyy... I know some of you need bullshit also :)

If you want to pass a behavior to a parameter (behavior= function=action) just create an interface and annotate it @FunctionalInterface and use Lambda Syntax like i did in above.

(param1,param2,,,,,paramN) -> {play with params}

Java 8 lots of built in @FunctionalInterface inside it. You can use them anywhere you need. Just  google for them .

Bye

Adapter Pattern VS Decorator Patter VS Facade Pattern VS Proxy Pattern VS Bridge Pattern - Summary - Table

I know this is not very presentable but it is easier to remember design patterns in the below format (at least for me).

Whatever...

Above is a list of Structural Design Patterns.

All of them is encapsulates some objects or interfaces and delegates the calls to them at the bottom . 

So what is difference between them on top of their behaviour ?

The difference is your intent !

And I don't recommend you to memorize them .Just read them once and hope to get an inspiration when you needed those.

Just encapsulate and delegate. --From "The Joy of Painting"

Favor object composition over class inheritance in Java with Project Lombok Delegate annotation

Subject: Object composition in Java via Lombok @Delegate annotation

Problem Statement : One common drawback of using composition instead of inheritance is that methods being provided by individual components may have to be implemented in the derived type, even if they are only forwarding methods. In contrast, inheritance does not require all of the base class's methods to be re-implemented within the derived class. Rather, the derived class only need to implement (override) the methods having different behavior than the base class methods. This can require significantly less programming effort if the base class contains many methods providing default behavior and only a few of them need to be overridden within the derived class.

Solution: This drawback can be avoided by using traits, mixins, or protocol extensions. Some languages, such as Perl 6, provide a handles keyword to facilitate method forwarding. In Java, Project Lombok lets you implement delegation using a single @Delegate annotation on the field instead of copying and maintaining names and types of all methods from the delegated field


Code : For the ones who says - "No bullshit , just the code..." :))

import lombok.Data;
@Data
public class BasicStudent {
    private String name;

    public void writeYourNameOnTheBlackBoard (){
        System.out.println ("There is no He/she/it in turkish because we are not sexists :) ");
    }
}


import lombok.experimental.Delegate;
public class EnhancedStudent {

    @Delegate
    BasicStudent beaFeaturesCameHereWithAnnotation;

}

public class StudentProcessor {
    public static void main (String[] args) {
        EnhancedStudent enhancedStudent = new EnhancedStudent ();
        enhancedStudent.writeYourNameOnTheBlackBoard ();
    }
}


 -- for the memory of Christoph Portman