π° Java Roadmap for Beginners 2025
βββ β Introduction to Java
βββ π Setup & IDEs
βββ π’ Variables & Data Types
βββ π Operators & Expression
βββ π Control Flow (if-else...)
βββ π Loops (for, while....)
βββ π Methods in Java
βββ π String Manipulation
βββ π¦ Arrays & Collections
βββ π OOPs
βββ β οΈ Exception Handling
βββ π File Handling in Java
βββ π Multithreading
βββ π Java for Web Dev
React β€οΈ for more
βββ β Introduction to Java
βββ π Setup & IDEs
βββ π’ Variables & Data Types
βββ π Operators & Expression
βββ π Control Flow (if-else...)
βββ π Loops (for, while....)
βββ π Methods in Java
βββ π String Manipulation
βββ π¦ Arrays & Collections
βββ π OOPs
βββ β οΈ Exception Handling
βββ π File Handling in Java
βββ π Multithreading
βββ π Java for Web Dev
React β€οΈ for more
β€10π₯2π₯°2
Java projects with tutorial π
Supermarket Management: https://youtube.com/playlist?list=PL-cxzMmn1xXEvQLajE2zYEfeF11lISJ0c&si=RwNa9HRFsrfFYvIy
Bank Management: https://youtube.com/playlist?list=PL_6klLfS1WqE1-_MJgZiJqAaccjLGHh0H&si=mw6PqEsAhrYskQjg
Cafe Management: https://youtube.com/playlist?list=PLdRq0mbeEBmwdwZF3lWwCcWmD76GfEFVT&si=opkQC14_5p3t0xBp
Chatbot: https://youtu.be/QP4HsdEPd-M?si=flwWw07VrWxr8qVY
Voting application: https://youtube.com/playlist?list=PLhHaibdHQVE1i3qWow-Mp0W_OrBrq1ykg&si=mtKqYDMxvgrMc97x
Food delivery: https://youtube.com/playlist?list=PL4fpXNDGXCyWXY7Sb_bp9VEENEW_UsG75&si=jHcdxrgbhbwvDqwa
University management: https://youtube.com/playlist?list=PL_6klLfS1WqH8iVglMyh7FVniAvD9Ar-E&si=i5jv8e6oj76BKQ7K
πFree Courses, Jobs, Intermships Whatsapp Group π₯ : https://whatsapp.com/channel/0029VamdH5mHAdNMHMSBwg1s
Supermarket Management: https://youtube.com/playlist?list=PL-cxzMmn1xXEvQLajE2zYEfeF11lISJ0c&si=RwNa9HRFsrfFYvIy
Bank Management: https://youtube.com/playlist?list=PL_6klLfS1WqE1-_MJgZiJqAaccjLGHh0H&si=mw6PqEsAhrYskQjg
Cafe Management: https://youtube.com/playlist?list=PLdRq0mbeEBmwdwZF3lWwCcWmD76GfEFVT&si=opkQC14_5p3t0xBp
Chatbot: https://youtu.be/QP4HsdEPd-M?si=flwWw07VrWxr8qVY
Voting application: https://youtube.com/playlist?list=PLhHaibdHQVE1i3qWow-Mp0W_OrBrq1ykg&si=mtKqYDMxvgrMc97x
Food delivery: https://youtube.com/playlist?list=PL4fpXNDGXCyWXY7Sb_bp9VEENEW_UsG75&si=jHcdxrgbhbwvDqwa
University management: https://youtube.com/playlist?list=PL_6klLfS1WqH8iVglMyh7FVniAvD9Ar-E&si=i5jv8e6oj76BKQ7K
πFree Courses, Jobs, Intermships Whatsapp Group π₯ : https://whatsapp.com/channel/0029VamdH5mHAdNMHMSBwg1s
β€9π2
Java_OOP-Cheat_Sheet.pdf
255 KB
Java OOP Concepts Cheat Sheet βπ
Master Javaβs Object-Oriented pillars:
πΉ Class & Object
πΉ Inheritance
πΉ Polymorphism
πΉ Abstraction
πΉ Encapsulation
React β€οΈ if you love clean Java code!
Master Javaβs Object-Oriented pillars:
πΉ Class & Object
πΉ Inheritance
πΉ Polymorphism
πΉ Abstraction
πΉ Encapsulation
React β€οΈ if you love clean Java code!
β€16
Java developer - Realistic Approach πͺπ©΅
1. Learn Java as a whole:
πBeginner :
- Java Core: Java syntax , Collections framework , Exception Handling , Multithreading ,
File Handling
- Java Intermediate - JDBC , Design Pattern , Generics etc.
πͺPro :
- Advanced Java - Lambdas , streams , time , concurrency utilities , JVM internals
- Design Patterns - Creational , Structural , Behavioral
2. Build Tools:
- Learn and use popular build tools like :
πBeginner : Maven (Web development) Gradle (App development)
πͺPro : Ant
3. Version Control:
- Master a version control system like Git. Master the skills for
πBeginner : Github
πͺPro : GitLab , BitBucket
4. Command Line (This can be done parallel to the above 4)
Believe me when it comes to Java development Command line skills will be a boon for you guys.
Start with the basics for eg : install and setup java with Command Line only.
Start using Linux distributions ( it's very necessary ) go to a virtual box or dual boot your systems with any of Ubuntu , Kali Linux , Manjaro etc
5. Learn Servlets and JSP and then go for a framework ( Spring boot
Best Programming Resources: https://topmate.io/coding/898340
Join for more: https://t.me/programming_guide
ENJOY LEARNING ππ
1. Learn Java as a whole:
πBeginner :
- Java Core: Java syntax , Collections framework , Exception Handling , Multithreading ,
File Handling
- Java Intermediate - JDBC , Design Pattern , Generics etc.
πͺPro :
- Advanced Java - Lambdas , streams , time , concurrency utilities , JVM internals
- Design Patterns - Creational , Structural , Behavioral
2. Build Tools:
- Learn and use popular build tools like :
πBeginner : Maven (Web development) Gradle (App development)
πͺPro : Ant
3. Version Control:
- Master a version control system like Git. Master the skills for
πBeginner : Github
πͺPro : GitLab , BitBucket
4. Command Line (This can be done parallel to the above 4)
Believe me when it comes to Java development Command line skills will be a boon for you guys.
Start with the basics for eg : install and setup java with Command Line only.
Start using Linux distributions ( it's very necessary ) go to a virtual box or dual boot your systems with any of Ubuntu , Kali Linux , Manjaro etc
5. Learn Servlets and JSP and then go for a framework ( Spring boot
Best Programming Resources: https://topmate.io/coding/898340
Join for more: https://t.me/programming_guide
ENJOY LEARNING ππ
β€5π₯1π1
Typical java interview questions sorted by experience
Junior
* Name some of the characteristics of OO programming languages
* What are the access modifiers you know? What does each one do?
* What is the difference between overriding and overloading a method in Java?
* Whatβs the difference between an Interface and an abstract class?
* Can an Interface extend another Interface?
* What does the static word mean in Java?
* Can a static method be overridden in Java?
* What is Polymorphism? What about Inheritance?
* Can a constructor be inherited?
* Do objects get passed by reference or value in Java? Elaborate on that.
* Whatβs the difference between using == and .equals on a string?
* What is the hashCode() and equals() used for?
* What does the interface Serializable do? What about Parcelable in Android?
* Why are Array and ArrayList different? When would you use each?
* Whatβs the difference between an Integer and int?
* What is a ThreadPool? Is it better than using several βsimpleβ threads?
* What the difference between local, instance and class variables?
Mid
* What is reflection?
* What is dependency injection? Can you name a few libraries? (Have you used any?)
* What are strong, soft and weak references in Java?
* What does the keyword synchronized mean?
* Can you have βmemory leaksβ on Java?
* Do you need to set references to null on Java/Android?
* What does it means to say that a String is immutable?
* What are transient and volatile modifiers?
* What is the finalize() method?
* How does the try{} finally{} works?
* What is the difference between instantiation and initialisation of an object?
* When is a static block run?
* Why are Generics are used in Java?
* Can you mention the design patterns you know? Which of those do you normally use?
* Can you mention some types of testing you know?
Senior
* How does Integer.parseInt() works?
* Do you know what is the βdouble check lockingβ problem?
* Do you know the difference between StringBuffer and StringBuilder?
* How is a StringBuilder implemented to avoid the immutable string allocation problem?
* What does Class.forName method do?
* What is Autoboxing and Unboxing?
* Whatβs the difference between an Enumeration and an Iterator?
* What is the difference between fail-fast and fail safe in Java?
* What is PermGen in Java?
* What is a Java priority queue?
* *s performance influenced by using the same number in different types: Int, Double and Float?
* What is the Java Heap?
* What is daemon thread?
* Can a dead thread be restarted?
Source: medium.
Junior
* Name some of the characteristics of OO programming languages
* What are the access modifiers you know? What does each one do?
* What is the difference between overriding and overloading a method in Java?
* Whatβs the difference between an Interface and an abstract class?
* Can an Interface extend another Interface?
* What does the static word mean in Java?
* Can a static method be overridden in Java?
* What is Polymorphism? What about Inheritance?
* Can a constructor be inherited?
* Do objects get passed by reference or value in Java? Elaborate on that.
* Whatβs the difference between using == and .equals on a string?
* What is the hashCode() and equals() used for?
* What does the interface Serializable do? What about Parcelable in Android?
* Why are Array and ArrayList different? When would you use each?
* Whatβs the difference between an Integer and int?
* What is a ThreadPool? Is it better than using several βsimpleβ threads?
* What the difference between local, instance and class variables?
Mid
* What is reflection?
* What is dependency injection? Can you name a few libraries? (Have you used any?)
* What are strong, soft and weak references in Java?
* What does the keyword synchronized mean?
* Can you have βmemory leaksβ on Java?
* Do you need to set references to null on Java/Android?
* What does it means to say that a String is immutable?
* What are transient and volatile modifiers?
* What is the finalize() method?
* How does the try{} finally{} works?
* What is the difference between instantiation and initialisation of an object?
* When is a static block run?
* Why are Generics are used in Java?
* Can you mention the design patterns you know? Which of those do you normally use?
* Can you mention some types of testing you know?
Senior
* How does Integer.parseInt() works?
* Do you know what is the βdouble check lockingβ problem?
* Do you know the difference between StringBuffer and StringBuilder?
* How is a StringBuilder implemented to avoid the immutable string allocation problem?
* What does Class.forName method do?
* What is Autoboxing and Unboxing?
* Whatβs the difference between an Enumeration and an Iterator?
* What is the difference between fail-fast and fail safe in Java?
* What is PermGen in Java?
* What is a Java priority queue?
* *s performance influenced by using the same number in different types: Int, Double and Float?
* What is the Java Heap?
* What is daemon thread?
* Can a dead thread be restarted?
Source: medium.
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π Top 10 Java Frameworks You Should Know π
Hereβs a quick guide to the most popular Java frameworks every developer should explore:
1οΈβ£ Spring: A powerful, versatile framework for building web applications and enterprise-level projects.
2οΈβ£ Hibernate: Simplifies database operations with its ORM (Object Relational Mapping) capabilities.
3οΈβ£ Struts: Ideal for creating scalable and maintainable enterprise-ready Java web applications.
4οΈβ£ Google Web Toolkit (GWT): Perfect for creating complex browser-based applications, especially with Java-to-JavaScript compilation.
5οΈβ£ JavaServer Faces (JSF): Simplifies web app development by connecting UI components to server-side data.
6οΈβ£ Grails: A Groovy-based framework designed for simplifying Java app development.
7οΈβ£ Vaadin: Focuses on modern web application development with an appealing UI and seamless integration.
8οΈβ£ Blade: A lightweight and high-performance framework for building fast REST APIs.
9οΈβ£ Dropwizard: Combines libraries to quickly create reliable, production-ready applications.
π Play: A reactive web application framework that supports both Java and Scala.
π‘ Explore these frameworks to stay ahead in your Java development journey! π
#JavaFrameworks
Hereβs a quick guide to the most popular Java frameworks every developer should explore:
1οΈβ£ Spring: A powerful, versatile framework for building web applications and enterprise-level projects.
2οΈβ£ Hibernate: Simplifies database operations with its ORM (Object Relational Mapping) capabilities.
3οΈβ£ Struts: Ideal for creating scalable and maintainable enterprise-ready Java web applications.
4οΈβ£ Google Web Toolkit (GWT): Perfect for creating complex browser-based applications, especially with Java-to-JavaScript compilation.
5οΈβ£ JavaServer Faces (JSF): Simplifies web app development by connecting UI components to server-side data.
6οΈβ£ Grails: A Groovy-based framework designed for simplifying Java app development.
7οΈβ£ Vaadin: Focuses on modern web application development with an appealing UI and seamless integration.
8οΈβ£ Blade: A lightweight and high-performance framework for building fast REST APIs.
9οΈβ£ Dropwizard: Combines libraries to quickly create reliable, production-ready applications.
π Play: A reactive web application framework that supports both Java and Scala.
π‘ Explore these frameworks to stay ahead in your Java development journey! π
#JavaFrameworks
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