Java Programming Language
Java is one of the most popular and widely used programming languages.
- Java has been one of the most popular programming languages for many years.
- Java is Object Oriented. However, it is not considered as pure object-oriented as it provides support for primitive data types (like int, char, etc)
- The Java codes are first compiled into byte code (machine-independent code). Then the byte code runs on Java Virtual Machine (JVM) regardless of the underlying architecture.
- Java syntax is similar to C/C++. But Java does not provide low-level programming functionalities like pointers. Also, Java codes are always written in the form of classes and objects.
- Java is used in all kinds of applications like Mobile Applications (Android is Java-based), desktop applications, web applications, client-server applications, enterprise applications, and many more.
- When compared with C++, Java codes are generally more maintainable because Java does not allow many things which may lead to bad/inefficient programming if used incorrectly. For example, non-primitives are always references in Java. So we cannot pass large objects (like we can do in C++) to functions, we always pass references in Java. One more example, since there are no pointers, bad memory access is also not possible.
- When compared with Python, Java kind of fits between C++ and Python. The programs are written in Java typically run faster than corresponding Python programs and slower than C++. Like C++, Java does static type checking, but Python does not.
Simple Hello World Program :
// A Java program to print "Hello World" public class GFG { public static void main(String args[]) { System.out.println("Hello World"); } }
Output:
Hello World
Java Programs – Basics to Advanced
Overview, Basics, Input/Output, Flow Control, Operators, Strings, Arrays, OOPs Concepts, Inheritance, Abstraction, Encapsulation, Polymorphism, Constructors, Methods, Interfaces, Wrapper Classes, Keywords, Access Modifiers, Memory Allocation, Classes, Packages, Collection Framework, List, Queue, Map, Set, Exception Handling, Multithreading, Synchronization, File Handling, Regex, Java IO, Networking, Java 8 Features, Date & Time, JDBC, Miscellaneous, Interview Questions
- Introduction to Java
- History of Java
- Java vs C++ Python
- How to Download and Install Java?
- Setting Up the Environment in Java
- How to Download and Install Eclipse on Windows?
- Java Development Kit (JDK) in Java
- JVM and its architecture
- Differences between JDK, JRE, and JVM
- Just In Time Compiler
- Difference Between JIT and JVM
- Difference Between Byte Code and Machine Code
- How is the Java platform independent?
Basics of Java
Input/Output in Java
- How to take Input from users in Java
- Scanner class in Java
- BufferedReader class in Java
- Scanner vs BufferedReader in Java
- Ways to Read Input from Console in Java
- Print Output in Java
- Difference between print() and println() in Java
- Formatted Outputs in Java
- Fast Input-Output for Competitive Programming in Java
Flow Control in Java
Operators in Java
Strings in Java
Arrays in Java
OOPS in Java
- OOPS Concept in Java
- Why Java is not a purely Object-Oriented Language?
- Classes and Objects
- Naming Convention in Java
- Methods in Java
- Access Modifiers in Java
- Constructors in Java
- Four pillars of OOPS in Java
- Inheritance in Java
- Abstraction in Java
- Encapsulation in Java
- Polymorphism in Java
- Interfaces in Java
- This reference in Java
Inheritance in Java
Abstraction in Java
Encapsulation in Java
Polymorphism in Java
Constructors in Java
Methods in Java
Interfaces in Java
Wrapper Classes in Java
Keywords in Java
Access Modifiers in Java
Memory Allocation in Java
Classes of Java
Packages in Java
Collection Framework
List
Queue
Map
Set
Exception Handling in Java
- Exceptions in java
- Types of Exceptions
- Difference between Checked and Unchecked Exceptions
- Try, Catch, Finally, throw, and throws
- Flow control in Try catch block
- Throw vs Throws
- Final vs Finally vs Finalize
- User-defined custom exception
- Chained Exceptions
- Null pointer Exceptions
- Exception handling with method Overriding
Multithreading in Java
- Introduction to Multithreading in Java
- Lifecycle and Stages of a Thread
- Thread Priority in Java
- Main Thread in Java
- Thread class
- Runnable interface
- How to name a thread
- start() method in thread
- Difference between run() and start() Method
- sleep() method
- Daemon thread
- Thread Pool in Java
- Thread Group in Java
- Thread Safety in Java
- ShutdownHook
- Multithreading Tutorial
Synchronization in Java
- Java Synchronization
- Importance of Thread synchronization in Java
- Method and Block Synchronization in Java
- Local frameworks vs thread synchronization
- Difference between Atomic, Volatile, and Synchronized in Java
- Deadlock in Multithreading
- Deadlock Prevention and Avoidance
- Difference between Lock and Monitor in Concurrency
- Reentrant Lock
File Handling in Java
Java Regex
Java IO
Java Networking
Java SE 8 Features
Java Date & Time
Java JDBC
Java Miscellaneous
Interview Questions on Java
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