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Java source files end with the .java extension and are compiled into .class files with the javac command. Every Java program defines a set of classes containing methods, with the main method serving as the entry point where program execution begins. Java uses semicolons, keywords, comments, and case sensitivity in source code syntax.
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Reviewer
- 1. Java source filesendwiththe .javaextension. Everyclass iscompiledintoaseparate bytecode file thathasthe same name as the class and endswiththe .classextension. To compile aJava source-code filefromthe commandline,use the javaccommand. To run a Java classfrom the commandline,use the javacommand. EveryJava program isa set of classdefinitions.The keywordclassintroducesaclassdefinition. The c ontentsof the class are includedinablock. A blockbeginswithanopeningbrace ({) andendswitha closingbrace (}).Methodsare containedina class. A Javaprogram must have a mainmethod.The mainmethodisthe entrypointwhere the program startswhenit isexecuted. EverystatementinJavaendswitha semicolon(;),knownasthe statementterminator. Reservedwords,orkeywords,have aspecificmeaningtothe compilerandcannotbe usedfor otherpurposesinthe program. In Java,commentsare precededbytwoslashes(//) ona line,calledaline comment,orenclosed between/*and*/onone or several lines,calledablockcomment. Java source programsare case sensitive.