Chapter 2       

Compilation and Execution of a Java Program


⦁ Java Language uses only one compiler javac.exe for all platforms.
⦁ After compilation of a java program every class in source code will convert into individual Byte code.
⦁ A Byte code can be execute on any operating system with help of Java Virtual Machine (JVM).
⦁ JVM consists an Interpreter (which is  Just-in-time compiler) can can convert Byte code into operating system readable form.
⦁ JVM differs fro compiler to compiler.
⦁ Java Developer Kit (Jdk) contains tools needed to develop the java program like compiler (javac.exe), Application Launcher (java.exe), etc.
⦁ Java Runtime Environment (Jre) contains JVM and Java package Classes (Java library).
⦁ Code for compilation a java program on command prompt :
javac FileName.java
⦁ Code for execution of java program on command prompt :
java FileName

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