Chapter 1 Java Evolution ie cmd X Java

Chapter 1 Java Evolution ie cmd X Java History. Java Features. Difference between java and C++. Java and Internet. H/w and S/w requirements. Java Environment.

Java History Java is a general purpose, Object oriented programming Language developed by Sun Microsystems of USA in 1991. Originally called Oak by James Gosling. Java Milestones 1990 – Sun Microsystems decided to develop special software for consumer electronic devices headed by James Gosling. ie cmd X 1991 – Using C++ the team announced a new language named Oak. 1992 – The Green project team by Sun, shown new language to control home appliances using hand held device with tiny touch-sensitive screen. a 1993 - The www appeared on the internet and transformed the text based internet into graphical rich environment using Web Applets. a 1994 – Team developed a web browser called “Hot. Java” for web Applets. a 1995 – “Oak” was renamed “Java” due to some legal snags. Java is just a name. Netscape and Microsoft supports to Java. a 1996 – Java established itself as a leader for internet & general purpose programming. Java founds its home.

Java Features ie cmd X ∆ Compiled and Interpreted ∆ Platform-Independent and Portable ∆ Object Oriented ∆ Robust and Secure ∆ Distributed ∆ Familiar, Simple and Small ∆ Multithreaded and Interactive ∆ High Performance ∆ Dynamic and Extensible

Difference between Java and C C++ C ie cmd X Java ▼ Java does not include keywords: goto, sizeof, and typedef. ▼ Java does not contain data types: struct, union and enum. ▼ Java does not define type modifiers: Auto, extern, register, signed & unsigned. ▼ Java does not support an explicit pointer type. ▼ Java does not have : #define, #include and #ifdef. ▲ Java adds new operator instanceof and >>> ▲ Java adds labeled break and continue statements. ▲ Java adds many features required for OOP.

Difference between Java and C++ C ie cmd X Java ▼ Java does not support operator overloading. ▼ Java does not have template classes. ▼ Java does not support multiple Inheritance. ▼ Java does not support global variables. ▼ Java does not use pointers. ▼ Java has replaced the destructor function with finalize method. ▼ There are no header files in Java.

Java and Internet Java is strongly associated with Internet because the first application program written in java was Hot. Java. ie cmd X Java & www : www is an open-ended information retrieval system to be used in internet’s distributed environment. Internet users can use Java to create Applets, In fact Java applets made the internet true extension of storage system of local computer. Java is purely known as Internet Language. HTML document communication. Web Browser. Remote Computer Internet Remote Applet Local computer

H/w & S/w Requirements IBM Compatible 486 system Minimum of 8 MB memory A hard drive ie cmd A CD-ROM drive A Microsoft compatible mouse A Windows compatible sound card if necessary X Windows 95 Software Web Browser Java Code.

Java Environment Appletviewer- (for viewing Java Applets) ie cmd X javac – (Java Compiler) java – (Java Interpreter) javah – (for C header files) javadoc – (for creating HTML documents) jdb – (Java debugger)