Core Java

An Introduction to Java

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Java is a well-designed programming language.
- But it isn't the epitome of elegance.
- It's a “blue collar” language.
Java is a platform:
- Good programming language.
- Efficient and secure execution environment.
- Huge library.
That combination has made it irresistible for over 20 years.

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Flash back to 1995.
Browsers were new and served static web pages.
Java applets made them alive.
Applet code is downloaded from the internet.
Runs safely in the “sandbox”.
Unfortunately, the initial excitement turned into frustration.
- Netscape and Internet Explorer used different Java versions.
- Flash provided dynamic effects in browsers.
- Sun and Oracle were slow to react to security breaches.
Nowadays, Java is used in servers and smart phones.

1991: James Gosling worked on “Project Green”, a system for consumer devices.
He designed a programming language, originally called “Oak”.
That name was trademarked, so it was renamed to “Java”.
1992: The first project was released, a TV switchbox called “*7”.
Nobody cared, and the project was renamed “First Person, Inc.”
1994: Still nobody cared, and Gosling realized that they could build a “really cool browser...architecture-neutral, real-time, reliable, secure.”
1995: HotJava was released.
1996: Java 1.0 was released.
1998: Java grows up with Java 2 release. SE, ME, EE edtions.
2014: Java 8 has major new language features.
2016: Java is again the #1 language in the TIOBE ratings.

Version	Year	New Language Features	Number of Classes and Interfaces
1.0	1996	The language itself	211
1.1	1997	Inner classes	477
1.2	1998	The `strictfp` modifier	1,524
1.3	2000	None	1,840
1.4	2002	Assertions	2,723
5.0	2004	Generic classes, “for each” loop, varargs, autoboxing, metadata, enumerations, static import	3,279
6	2006	None	3,793
7	2011	Switch with strings, diamond operator, binary literals, exception handling enhancements	4,024
8	2014	Lambda expressions, interfaces with default methods, stream and date/time libraries	4,240

Java is an extension of HTML or XML.: Java is a programming language.
Java is an easy programming language to learn.: No programming language as powerful as Java is easy.
Java will become a universal programming language for all platforms.: This is possible in theory, but today, Java is most commonly used in backend systems and Android applications.
Java is just another programming language.: Java has a support system that far exceeds that of most other languages.
Java is proprietary, and it should therefore be avoided.: Java is open source.

Java is interpreted, so it is too slow for serious applications.: The just-in-time compiler can produce code that is as fast as C++, and sometimes faster.
All Java programs run inside a web page.: Applets run in web pages, but most Java programs run on servers or mobile/embedded devices.
Java programs are a major security risk.: Applet security risks are real, but in general Java is very secure.
JavaScript is a simpler version of Java.: JavaScript was named after Java for marketing reasons.
With Java, I can replace my desktop computer with a cheap “Internet appliance.”: That was an expectation 20 years ago, and it may be true today if your Android smart phone or tablet has replaced your desktop.

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