Everything a Beginner Needs to Know About Java💻.
Introduction To Java Programming Language -
Java is a General Purpose, and object-oriented programming language design for the development. It was developed by James Gosling at Sun Microsystems of the USA in 1991 and released in 1995 as a core component of Sun Microsystems. The main feature about java is, it is platform-independent means once compiled you can execute the program on any platform because the source code of java i.e (java file) is converted into byte code which is Intermediate Language with the help of java compiler. This byte code can be executed on any platform using JVM(Java Virtual Machine) that's why java was developed with the concept “Write Once Run Anywhere”.
How Java Works -
Working of java is totally based on JVM(Java Virtual Machine) so understanding how JVM works will clear the concept “How Java Works”.
JVM-The Heart Of JAVA. It converts Java bytecode into machines language. JVM is a part of Java Run Environment (JRE). In other programming languages, the compiler produces machine code for a particular system. However, Java compiler produces code for a Virtual Machine known as Java Virtual Machine. In figure as shown above
- First, Java code (
.java) is complied into bytecode (.class). - This bytecode gets interpreted on different machine Between host system and Java source.
What is java used for-
Before Answer this question, let me clarify to you about why should you choose java. Because features of java such as Platform Independent, Secure, Robust, Multithreaded, Portable, Distributed, High-Performance Java is highly popular and has dominated this field from the early 2000s till the present 2020.
Java has been used in different domains. As shown in the below figure:
Popular Topics to Consider for a Java Interview-
You’ve got the interview — now what? While some job interviews can follow a straightforward, simple question and answer format, in the Java industry, preparing for an interview can be slightly more difficult.
So there are some topic areas to focus on when preparing for java interview and you just need to brush up on the following areas.
Concept From Core Java :
- OOPS concepts (Data Abstraction, Encapsulation, Inheritance, Polymorphism)
- All about JDK, JRE, JVM
- String handling
- Concept Final Block, Static Block
- Collection framework
- Exception Handling
- Multithreading
- Garbage Collection In Java
Advance Java Concept :
- JDBC (Java Database Connectivity)
- Servlet
- JSP
Popular frameworks :
- Spring (MVC, JDBC, ORM, AOP)
- Hibernate ORM framework
Here are some online sources to learn java and prepare for java interview-
Conclusion-
Finally, In this Java guide, we learned about the of Java programming language, How java Works, What is java used for and Popular Topics to Consider for a Java Interview. Hope this helps😇.
Thank You🙂
