![Object-Oriented Programming
HISTORY AND BACKGROUND OF JAVA
Java Program
class HelloWorld{ Compiler
public static void main(String args[ ]){
System.out.println(“Hello World”);
}
} Interpreter Interpreter
HelloWorld.java
Interpreter
Hello World
Hello World
Hello World
Win32 MacOS
Solaris
Information FEU – EAST ASIA COLLEGE
Technology
Department](https://image.slidesharecdn.com/1-introductiontojavatechnology-120623221607-phpapp02/85/1-introduction-to-java-technology-7-320.jpg)
1 introduction to java technology
- 1. Introduction to Java Technology Information FEU – EAST ASIA COLLEGE Technology Department
- 2. Object-Oriented Programming HISTORY AND BACKGROUND OF JAVA Java language, originally called the ‘Oak’, was originally developed by James Gosling at Sun Microsystems, which is now a subsidiary of Oracle Corporation, and released in 1995 as a core component of Sun Microsystems' Java platform. It has derived much of its syntax from C and C++ but has a simpler object model and fewer low-level facilities. Information FEU – EAST ASIA COLLEGE Technology Department
- 3. Object-Oriented Programming HISTORY AND BACKGROUND OF JAVA http://en.wikipedia.org/wiki/James_Gosling About James Gosling Information FEU – EAST ASIA COLLEGE Technology Department
- 4. Object-Oriented Programming HISTORY AND BACKGROUND OF JAVA Java is a general-purpose, concurrent, class-based, object-oriented language that is specifically designed to have as few implementation dependencies as possible. The Java source code files (files with .java extension) are compiled into a format called bytecode (files with .class extension), which can be executed by a Java interpreter. Information FEU – EAST ASIA COLLEGE Technology Department
- 5. Object-Oriented Programming HISTORY AND BACKGROUND OF JAVA It was intended for use in Sun’s project research to work on a programming software to control electronic devices. It was modified to take advantage of the World Wide Web. The WebRunner, later named as HotJava, was the very first web browser created in Java. In 1995, the Netscape Navigator internet browser was also developed to support Java. Information FEU – EAST ASIA COLLEGE Technology Department
- 6. Object-Oriented Programming HISTORY AND BACKGROUND OF JAVA Features of Java: 3.Simple, Object-oriented, and Familiar 5.Robust and Secure 7.Architecture Neutral and Portable 9.High Performance 11.Interpreted, Threaded, and Dynamic Information FEU – EAST ASIA COLLEGE Technology Department
- 7. Object-Oriented Programming HISTORY AND BACKGROUND OF JAVA Java Program class HelloWorld{ Compiler public static void main(String args[ ]){ System.out.println(“Hello World”); } } Interpreter Interpreter HelloWorld.java Interpreter Hello World Hello World Hello World Win32 MacOS Solaris Information FEU – EAST ASIA COLLEGE Technology Department
- 8. Object-Oriented Programming HISTORY AND BACKGROUND OF JAVA myProgram.java _________________ Interpreter _____________ _______________ My Program myProgram.class Compiler _________________ _____________ _______________ The Java source code (.java file) is normally compiled to produce the bytecode file (.class file) which is normally interpreted by the Java virtual machine (JVM) Information FEU – EAST ASIA COLLEGE Technology Department
- 9. Object-Oriented Programming HISTORY AND BACKGROUND OF JAVA Java Editions: J2SE Java 2 Standard Edition J2EE Java 2 Enterprise Edition J2ME Java 2 Micro Edition Information FEU – EAST ASIA COLLEGE Technology Department
- 10. Object-Oriented Programming HISTORY AND BACKGROUND OF JAVA The Java Virtual Machine (JVM) Java is a portable language that could run on any platform. The language was able to do this by generating intermediate code for a hypothetical computer called a virtual machine. The Java Virtual Machine (JVM) is a program that runs on all computers. The JVM creates a software simulation of a CPU and memory and handles all communication between the Java program and the underlying operating system and hardware. Information FEU – EAST ASIA COLLEGE Technology Department
- 11. Object-Oriented Programming HISTORY AND BACKGROUND OF JAVA The JVM and Application Architecture Source Code “javac” Byte Code Information FEU – EAST ASIA COLLEGE Technology Department
- 12. Object-Oriented Programming HISTORY AND BACKGROUND OF JAVA The JVM and Application Architecture Byte Code Java Virtual Machine Machine Code Information FEU – EAST ASIA COLLEGE Technology Department
- 13. Object-Oriented Programming HISTORY AND BACKGROUND OF JAVA How JVM Works JVM for Windows OS Windows Byte code .class File (Java Application) “Write once, run JVM for Linux OS anywhere technology.” Linux Information FEU – EAST ASIA COLLEGE Technology Department
- 14. Object-Oriented Programming HISTORY AND BACKGROUND OF JAVA The J2SDK (JDK) Java 2 Software Development Kit contains java – the loader for Java applications javac – the compiler javadoc – the documentation generator other tools Information FEU – EAST ASIA COLLEGE Technology Department
- 15. Object-Oriented Programming HISTORY AND BACKGROUND OF JAVA Steps in Creating a Java Application 3.Create the source code. 4.Compile the source code. 5.Run the program. Information FEU – EAST ASIA COLLEGE Technology Department
- 16. Object-Oriented Programming HISTORY AND BACKGROUND OF JAVA Steps 1 : Creating the Source Code Create the source code using any text editor. Save the file with a “.java” extension. Example: HelloJava.java Information FEU – EAST ASIA COLLEGE Technology Department
- 17. Object-Oriented Programming HISTORY AND BACKGROUND OF JAVA Steps 2 : Compiling the Source Code Compile the source code to create the bytecode using javac tool from the J2SDK. Open an MS-DOS console, browse for the directory where you saved the source code. Type the command javac HelloJava.java and press ENTER. Verify that the HelloJava.class has been created Information FEU – EAST ASIA COLLEGE Technology Department
- 18. Object-Oriented Programming HISTORY AND BACKGROUND OF JAVA Steps 3 : Running the Program To execute the program, type the command: java HelloJava and press ENTER. Information FEU – EAST ASIA COLLEGE Technology Department
- 19. Questions and Comments Information FEU – EAST ASIA COLLEGE Technology Department
Editor's Notes
- #7: Simple, Object-oriented, and Familiar Java can be programmed without extensive programmer training while being attuned to current software practices. The needs of distributed, client-server based systems coincide with the encapsulated, message-passing paradigms of object-based software. It looks like C++ as far as possible results in it being a familiar language, while removing the unnecessary complexities of C++. Robust and Secure It provides extensive compile-time checking, followed by a second level of run-time checking Java technology is designed to operate in distributed environments, which means that security is of paramount importance 3. Also mention fetures like garbage collection
- #8: Architecture Neutral and Portable Java technology is designed to support applications that will be deployed into heterogeneous network environments. To accommodate the diversity of operating environments, the Java compiler product generates bytecode – an architecture neutral intermediate format designed to transport code efficiently to multiple hardware and software platforms. The interpreted nature of Java technology solves both the binary distribution problem and the version problem; the same Java programming bytecodes will run on any platform. High Perforrnance The automatic garbage collector runs as a low priority background thread, ensuring a high probability that memory is available when required, leading to better performance. Interpreted, Threaded, and Dynamic The Java interpreter can execute the bytecodes directly on any machine to which the interpreter and run-time system have been ported. Java technology’s multi-threading capability provides the means to build applications with many concurrent threads of activity. Multi-threading thus results in a high degree of interactivity with end users. While Java compiler is strict in its compile-time static checking, the language and run-time system are dynamic in their linking stages.
- #9: Simple, Object-oriented, and Familiar Java can be programmed without extensive programmer training while being attuned to current software practices. The needs of distributed, client-server based systems coincide with the encapsulated, message-passing paradigms of object-based software. It looks like C++ as far as possible results in it being a familiar language, while removing the unnecessary complexities of C++. Robust and Secure It provides extensive compile-time checking, followed by a second level of run-time checking Java technology is designed to operate in distributed environments, which means that security is of paramount importance