Java
Download as PPT, PDF
0 likes256 views
This document provides an overview of how to install and begin using the Java programming language. It first gives a brief history of Java and its origins in the 1990s at Sun Microsystems. It then explains how to download and install the Java Development Kit (JDK) on a Windows computer, covering creating a temp directory, downloading the offline JDK file from Oracle's website, installing it typically in the C:\Java directory, and adding the bin path to the system PATH environment variable. Finally, it demonstrates a simple "Hello World" Java program using the javac compiler to create bytecode and java to run the program, showing the basic workflow of Java's compile and interpret process.
Java
- 1. Java How to find, install and begin to use the Java programming language.
- 2. A word or two on the history of some old fashion programming languages A small history of Java How do I install it on my computer? How do I use what I just installed? What were going to cover
- 3. A short look at some old school languages, BASIC, C and C++ It all begins in the sixties
- 4. BASIC BASIC stands for Beginners All-purpose Symbolic Instruction Code. It was designed in 1963 at Dartmouth college. It was designed to make it easy for non-technical people to write computer programs. BASIC programs were like grocery lists. You told the program what you wanted to do and it did it in order. BASIC was Interpreted.
- 5. C and C++ Developed in the early seventies, C became the de-facto language for microcomputer programming in the seventies and eighties. C was not interpreted, it was compiled. __________ Later, in the early eighties, C++ introduced object orientation to the C world. Originally called C with Classes, Bjarne Stroustrup developed the additions to C that, in 1985, became C++. OO is when programmers try to mimic the real world more closely and make programs act like objects and not just be grocery lists.
- 6. So, what have we learned? 1. BASIC was an interpreted programming language 2. C was a compiled programming language 3. C++ brought object orientation to C
- 7. Say goodbye to the seventies and welcome to a short (but hopefully informative) history of the Java programming language Authentic Seventies Nerds
- 9. James Gosling began developing Java beginning in 1991 It was first called Project Green and Oak First developed for remote cable TV boxes James Naughton creates HotJava in 1995. its a web browser that lets you run Applets. The entire browser is written in Java. In 1998 Java 1.2 is released Java just released version 1.6 or J2SE 6 James Gosling Circa 1971 James Gosling Today
- 10. Java Buzzwords Simple Object Oriented Architecture Neutral Portable Multithreaded High Performance JIT Buzzwords glommed from the Core Java 2 book verbatim
- 11. FREE
- 12. Is Java Interpreted or Compiled?
- 13. Is Java Interpreted or Compiled? BOTH!! Java programs are compiled to Bytecode Bytecode is then interpreted by a JVM, or Java Virtual machine. The virtual machine is what runs your program Its the JVM that cares about your Operating system, NOT THE PROGRAM! WORA - Write Once, Run Anywhere!
- 14. Is Java Object Oriented?
- 15. Is Java Object Oriented? YES! Every bit of code in a Java program is in a Class Code Reuse, Encapsulation, Polymorphism, Inheritance
- 18. Downloading a Java JDK You want a JDK, not just a JRE Create a Temp directory on your PC or laptop Go to http://java.sun.com Go to the Popular Downloads section and select Java SE Select a JDK without Netbeans (Well talk about this later) Agree to the accept the use policy Right Click and Save the Offline Windows JDK to your temp dir
- 19. Installing a Java JDK Go to your Temp dir using Windows Explorer Make sure no other apps are running and double click the install program you just downloaded. Follow the steps. I install in C:Java Watch fom multiple JREs and JDKs! In Windows the Registry runs the show now, not the JAVA_HOME env variable Test with a Command Prompt Window and java version Add C:JavaJava verbin to your PATH var Be sure to add current directory to the CLASSPATH (if you had one)
- 20. Now, Lets test it DOS - Command Prompt Make a directory structure Type Edit and Voila PSVM Test JAVAC and JAVA Create Bytecode ( the *.class file) with Javac Run Program with Java
- 21. If we were lucky we got something that looks like this
- 22. Help on the Web http://java.sun.com/javase/6/docs/api/ http://www.javaranch.com http://java.sun.com/docs/books/tutorial/ http://www.sorcon.com/java2/ http://remus.rutgers.edu/freestuff Got an Error? Just type it verbatim into Google and you usually can find the answer to your question or solve your problem. Wikipedia is a good place to get background and history On anything, and Java is no exception
- 23. Remember. Java is both compiled and interpreted Java is Object Oriented http://java.sun.com is Javas home You want the Java Development Kit (JDK) , not a JRE or J2EE Take your time, use temp directories for setup files Test with a simple Hello World after you install Use the Web for help (Google errors, javaranch, etc.)
- 24. THANK YOUhttp:remus.rutgers.edujavaworkshops Any questions or comments can be sent to me At biglars@cs.rutgers.edu Be Good Now 息2007 Rutgers University & Lars Sorensen