Java was created in 1991 by James Gosling at Sun Microsystems and was originally called Oak. It was designed to be platform independent and wrote code that ran on any system with a Java Virtual Machine (JVM). Java uses object-oriented programming concepts like classes, objects, inheritance and interfaces and became popular for building web apps and mobile apps due to its ability to write once and run anywhere.

2. Hardware
, , , , Set
Top Box James
Gosling Green Group Sun
Microsystems
1991 Oak
Sun Microsystems
Write Once Run Anywhere Oak
Object Oriented
1995
Visual J Microsoft Visual Cafe
Sysmantec Jbuilder Borland

3. Object Oriented
Object
Oriented C
Object
Oriented
Plateform Object Oriented
Object Model
Object Oriented
Object
class, function array

4. Platform Platform
Independent
source code class
JVM Java Vitual Machine
Interpreter
Virtual
Processer Interpreter JVM

5. •
C C
•
Parameter
• Pointer
Allocate Deallocate
(Allocate) Deallocate
•
•

6. HTML
Page
Standalone
class interpreter
Java exe
HTML Page
Tag
Netscape Navigator,
Microsoft Internet Exporler HotJava
interpreter

7. Variable
, ,
· instance instance variables
· class variables
· local variables