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We will talking about story of JAVA language.
By Kristsada Songpartom
Java works well for web and server-based
applications. It has great features like objectoriented programming, easy database access, and
well-designed GUI support.Java has performance
tweaks to speed up desktop programs. There are
libraries for communicating across networks, and
for encryption. It has strong security built in. Most
programmers pick up Java quickly. Behind all this,
Java is more than just the latest, most popular
programming language. It is a way of creating
applications that are independent of all hardware
and all operating systems.
History of JAVA
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Sun Microsystems in 1991 funded an internal
corporate research project code-named Green,
which resulted in the development of a C++-based
language that its creator, James Gosling, called
Oak after an oak tree outside his window at Sun. It
was later discovered that there already was a
computer language called Oak. When a group of
Sun people visited a local coffee shop, the name
Java was suggested, and it stuck. And Sun formally
announced Java at a major conference in May
1995.
Why must be JAVA ?
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We want software that works—consistently,
anywhere, on any platform—and that plays well
with other applications. We want dynamic
applications that take advantage of a connected
world, capable of accessing disparate and
distributed information sources. We want truly
distributed software that can be extended and
upgraded seamlessly. We want intelligent
applications—such as autonomous agents that can
roam the Net for us, ferreting out information and
serving as electronic emissaries.
Primary goals
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There were five primary goals in the creation of the
Java language
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1. It should use the object-oriented programming
methodology.
2. It should allow the same program to be executed on
multiple operating systems.
3. It should contain built-in support for using computer
networks.
4. It should be designed to execute code from remote
sources securely.
5. It should be easy to use by selecting what were
considered the good parts of other object-oriented
languages.
Main features of the JAVA

"Write once, run anywhere" (WORA)
Java can be developed on any device,
compiled into a standard bytecode and be
expected to run on any device equipped with a
Java virtual machine (JVM). The installation of
a JVM or Java interpreter on chips.
Some good things about Java
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Java has a garbage collector so there are no destructors.
Memory management is handled by the system, not by each
program.
Java catches all array subscript errors and similar. Java never
has uninitialized data of any kind. Order of evaluation, etc. is
completely defined and natural.
Java arrays know their own length. (a public read-only field
named length.)
Java never has dangling references. You still can't derefernce
null, however. If you try it will be caught. This is probably the
most common run time error.
Java int, float,... are completely defined, so behave the same on
all systems supporting Java. Int is 32 bits with modular
arithmetic. In fact the only thing in Java not specified is the
effect of the interleaving of threads in a multithreaded
program. All casts are checked, either at compile time or at
runtime. A narrowing cast is never applied automatically.
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Java interfaces define first class types. This gives most of the
strength of both C++ templates and multiple inheritance.
Interfaces are very important in Java.
Java has threads, so concurrent programs are possible with
standard tools.
Java has a library with lots of common data structures.
Some bad things about Java
(Actually these things are good, but are placed here
since they complicate novice learning.)

I/O takes explanation and getting used to. Java standard
output is easy. Java standard input is harder. Other
input/output is hard. (But its object model is very good.)

Java exceptions must be caught and i/o statements throw
exceptions.
Simple Programs
Hello Java program.
public class helloJava {
public static void main(String[] args) {
String hello = "Hello Java";
System.out.println(hello);
//the program will show hello and we want to add number then see below.
int a = 321;
int b = 123;
int c = a+b;
int d = a+b*c+1+2+3;
System.out.println(c);
System.out.println(d);
}
}
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We have more information in http://garnet.cpe.ku.ac.th/wiki/index.php/JAVA
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