Section 10: Advanced Java Concepts

Lesson 1: Design Patterns in Java

1.1 Introduction to Design Patterns

Understanding the significance of design patterns in software development.

Overview of common design patterns and their purposes.

1.2 Applying Design Patterns in Java

Exploring and implementing design patterns in Java.

Examples of commonly used design patterns such as Singleton, Factory, and Observer.

Example (Singleton Design Pattern):

public class Singleton {

    private static Singleton instance;

    // Private constructor to prevent instantiation

    private Singleton() {

    }

    // Lazily initialize the instance if needed

    public static Singleton getInstance() {

        if (instance == null) {

            instance = new Singleton();

        }

        return instance;

    }

}

Lesson 2: Java 8 Features

2.1 Lambdas and Functional Interfaces

Introduction to lambdas as a concise way to express anonymous functions.

Working with functional interfaces and their role in lambda expressions.

Example (Lambda Expression):

// Traditional approach without lambda

Runnable traditionalRunnable = new Runnable() {

    @Override

    public void run() {

        System.out.println("Hello, Traditional!");

    }

};

// Lambda expression for the same Runnable

Runnable lambdaRunnable = () -> System.out.println("Hello, Lambda!");

2.2 Stream API

Understanding the Stream API for processing collections in a functional style.

Performing operations on streams such as filter, map, and reduce.

Example (Stream API):

import java.util.Arrays;

import java.util.List;

public class StreamExample {

    public static void main(String[] args) {

        List<String> languages = Arrays.asList("Java", "Python", "JavaScript", "Ruby");

        // Using Stream API to filter and print elements

        languages.stream()

                 .filter(lang -> lang.startsWith("J"))

                 .forEach(System.out::println);

    }

}

Java 8 introduced significant features that enhance code conciseness and expressiveness. Understanding and applying design patterns along with leveraging Java 8 features like lambdas and the Stream API contribute to writing more efficient and maintainable Java code. Practice incorporating these advanced concepts into your Java development projects.