Definition of java:
- Java is a very simple, high level , secured, concurrent, platform independent. object-oriented programming language.
- It is descendant of c , c++ programming language.
- Its syntax is similar to c and c++ , but it omits many of the features that makes c and c++ complex, confusing and unsafe.
- So, in java we can not see that most horrible topics such as pointers, struct, union, operator overloading, multiple inheritance etc..
Java Technology:
- Unlike other programming languages , java technology is both platform and programming language.
- Platform means it is the hardware or software environment in which programs are executed.
- Java has its own software based platform called JVM-Java virtual machine - to execute java programs.
Java History:
- The java platform was initially developed to address the problems of building software for networked consumer electronic devices.
- It was designed to support multiple host architectures and to allow secure delivery of software components
- To meet requirements , compiled code has to survive transport across networks, operate on any client , and assure the client that it was safe to run.
- Before java language , the software for these consumer electronic devises such as washing machines, microwave ovens and micro controllers was developed by c, c++.
- These languages are platform independent.
- So we require a platform independent language that could be used to create software to be embedded in various consumer electronic devices.
- In an attempt to find such a solution, in sun micro systems a team headed with a scientist
James gosling began work on portable, platform independent language that could be used to produce code that work on portable, platform independent language that could be used to produce code that would support any technology any time. - Initially they named that language as OAK. its tree name.
- Its was all happened in the middle of 1991 and the late 1992.
- In the mean time enhancing this OAk language to make more efficient language te world wide web was emerging into the market .
- In www so many varieties of CPUs under different environments will be connected.
- So here also we require a portable and platform independent language .
- The only solution for this problem is OAK.
- So this OAK language was modified or enhanced to fulfill the requirements of internet programming and in 1995 it was renamed to "JAVA".
Why the name OAK renamed to JAVA?
- They were unable to register this programing language with name OAK, because already some other product is registered with the same name . so they renamed to JAVA.
Abbreviation of JAVA?
- There is no abbreviation for java. The development team has just chosen this name.
- The name java specifically doesn't have any meaning rather it to the hot, aromatic drink COFFEE.
- This is the reason java programming language ICON is Coffee Cup.
Who Developed Java?
- James Gosling, PhD(born on may 19, 1955, canada) along with other engineer scientists discovered java at bell laboratories. He is famous software developer, best known as the father of java programming language.
Java Features
- Simple
- Object Oriented
- Secure
- Multithreaded
- Robust
- High Performence
- Portable
- Distributed
- Architecture Neutral
- Dynamic
Java Definition based on features:
- Java is just a simple , secure, robust, portable, object oriented, interpreted , byte coded, architectural neutral(Platform independent), garbage collected, multithreaded programming language with strongly typed exception handling mechanisms for writing distributed, dynamically extensible programs.
Why Java?
- Java programming language mainly designed to develop platform in-dependency for supporting internet applications development.
Terminology used in Programming languages:
Source Code:
- Developer written program that is written according to the programming language syntax.
Compiled Code:
- Compiler generated program that is converted from source code.
Executable Code:
- Os understandable readily executable program.
Compiler:
- It is a translation program that converts source code in to machine level at once.
Interpreter:
- It is also a translator program that converts source code into machine language but line by line.
Compilation:
- It is process of translating source code into compiled code.
Execution:
- It is the process of running compiled code to get output.