![JDK Versions
• History of JDK version
– https://en.wikipedia.org/wiki/Java_version_history
• Latest is Java SE 18 [Java SE 18]
• Download from:
– https://www.oracle.com/java/technologies/downloa
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Lecture-2.pptx sensor design and signal processing using RF and THz sensing, specifically for physiological measurements. He is highly motiv
- 2. About Java • Java is a powerful and versatile programming language for developing software running on mobile devices, desktop computers, and servers • Developed by James Gosling in 1995 • Popular because of write a program once and run it anywhere • Java is a programming language and a platform • Platform: Any hardware or software environment in which a program runs, is known as a platform. Since Java has a runtime environment (JRE) and API, it is called a platform.
- 3. Types of Java Applications • Four types of applications that can be created using Java programming – Standalone Application – Web Application – Enterprise Application – Mobile Application
- 4. JDK Editions • Java Standard Edition (Java SE) • Java Enterprise Edition (Java EE) • Java Micro Edition (Java ME)
- 5. JDK Versions • History of JDK version – https://en.wikipedia.org/wiki/Java_version_history • Latest is Java SE 18 [Java SE 18] • Download from: – https://www.oracle.com/java/technologies/downloa ds/#jdk18-windows
- 6. Installing Java • To check if Java is installed (open command prompt and type following command) java –version • Setting Java Path – Temporary Path • Open the command prompt • Copy the path of the JDK/bin directory • Write in command prompt: set path=copied_path – Permanent Path using Environment Variables Settings
- 7. Environment Variable • Go to "System Properties" (Can be found on Control Panel > System and Security > System > Advanced System Settings) • Click on the "Environment variables" button under the "Advanced" tab • Then, select the "Path" variable in System variables and click on the "Edit" button • Click on the "New" button and add the path where Java is installed, followed by bin. By default, Java is installed in C:Program FilesJavajdk-15bin Then, click "OK", and save the settings • At last, open Command Prompt (cmd.exe) and type java - version to see if Java is running on your machine
- 8. Popular Java IDEs • NetBeans • Eclipse • IntelliJ
- 9. JDK, JRE, and JVM • Java Virtual Machine (JVM) – Provides a platform-independent way of executing Java source code – JVM comes with JIT(Just-in-Time) compiler that converts Java source code into low-level machine language • Java Runtime Environment – Set of software tools which are used for developing Java applications – Contains JVM – JRE = JVM + rt.jar (lang, util, awt, swing, math packages) • Java Development Tool kit (JDK) – Software development environment which is used to develop Java applications – Physically exists
- 10. JDK, JRE, and JVM
- 11. Interpreting/Compiling Source Code • A program written in a high-level language is called a source program or source code • A source program must be translated into machine code for execution
- 12. Compiling Source Code A compiler translates the entire source code into a machine-code file, and the machine-code file is then executed
- 13. Interpreting Source Code An interpreter reads one statement from the source code, translates it to the machine code or virtual machine code, and then executes it right away
- 14. Creating, Compiling, and Running Programs
- 15. Java Program Phases • Phase 1: Creating a Program • Phase 2: Compiling a Java Program into Bytecodes – Bytecodes are re-executed by the JVM
- 16. Java Program Phases • Phase 3: Loading a Program into Memory – JVM class loader takes the .class file (along with associated class files provided by Java) and loads in memory
- 17. Java Program Phases • Phase 4: Bytecode Verification – Java enforces strong security to make sure that Java programs arriving over the network do not damage your files or your system (as computer viruses and worms might).
- 18. Java Program Phases • Phase 5: Execution – Interpreter • JVM execute bytecode using interpreter (one bytecode at a time) which slows execution – Just In Time(JIT) Compiler • JVM analyzes the bytecodes as they’re interpreted searching for hot spots — parts of the bytecodes that execute frequently • For these part JIT also known as Java HotSpot compiler – Translates the bytecodes into the underlying computer’s machine language