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Key Words in java :

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JAVA RESERVED KEY WORDS Above listed  are reserved keywords  those key words are not posible to provide as method name / classname / variable name , every key word is having special meaning and role to use NOTE:All the keywords contains only lowercase alphabet symbols Keywords for primitive data types : byte,short,int,long float,double,char,boolean Keywords for flow control: if,else,switch,case,default,while do,for,break,continue,return Keywords for exception handling: try,catch,finally,throw throws,assert(for debugging purpose,1.4v) Keywords for modifiers: public,private,protected,static,final,abstract synchronized,native,transient,volatile,strictfp(1.2v) Class related Keywords: class,package,import,extends implements,interface Object related Keywords: new,instanceof,super,this void return type Keyword if a method doesn’t return anything compulsory we should declare that method with void return type. Unused Keywords: goto(usage is conside...

Java software

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Java software consists of 2 types : 1)Jre(java run time environment). 2)Jdk(Java development kit). Over view of JDK,JRE:     OVER VIEW OF JDK,JRE JRE  (Java run time environment):                                     Jre consists of JVM(java virtual machine which converts byte code to machine understandable language) and utility classes to run.                                     This is used to run java apps in our system,if you want to run java apps you have to install jre. only Jre is  required to client to run java apps . JDK  (Java development kit):                                      Jdk is used by developers to write,com...

Types of files in java

Java has 2 types of files : 1)<file_name>.java(file name with java extension). 2)<class_name).class(class name with class extension). .java Extension files:                   it's source code (i.e developer written code). All source code files will save with ".java" extension. .class Extension files:                  it's prepared by java compiler which is in the format of "bite code" (i.e JVM understanding code).

why name Java ?

Java is just a name derived from cup of coffee, at the time of java invention they named it as OAK it’s also a name of a tree and this name is already registered. At that time coffee with name JAVA got popularity with its taste regarding to the popularity they decided to their software as Java so it contains coffee cup as its symbol.

What is java?

Java is an Object Oriented  Programming  System, it’s used to develop Internet applications by achieving Platform  In dependence . Java is simple, secure, robust, portable, architectural neutral, object oriented, multi-threaded, high performance, distributed and dynamic  Programming  System that supports us to develop Internet applications development by achieving platform  in dependency . History of JAVA : Refer below link if you are interested.  http://en.wikipedia.org/wiki/Java_(programming_language)