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JIT compiler (Just-in-time compiler)
subject			fact

JIT compiler	has definition A compiler that converts all of the bytecode into native machine code just as a program is run
	has purpose to improve run-time speed over code that is interpreted by a Java virtual machine
	is part of an implementation of the Java Virtual Machine specification
	is a subtopic of How Java Works
	is a kind of compiler
	is a synonym of Just-in-time compiler
compiler	the compiler creates an output file for each class and interface defined in a source file when the source file is compiled
	the compiler will display an error message and the compiler will refuse to compile the program if you try to instantiate an abstract class
	the compiler will display an error message and the compiler will refuse to compile the program if you try to override a final method
	the compiler will display an error message and the compiler will refuse to compile the program if you try to assign to a final variable
	the compiler will display an error message and the compiler will refuse to compile the program if you try to compile a subclass of a final class
	chooses a constructor based on the number of the actual arguments and the types of the actual arguments
	compiles source code into bytecode
	puts compiled code into a class file with the same name as the source file but with extension .class
application	consists of one or more classes
	contains one class that contains a main method which serves as the starting point for the rest of the program
	has example of running java HelloWorld
	has part 1 main method called its entry point
	is similar to an applet
	is run by using a Java interpreter to load the application's main class file - this is normally done from the command-line prompt using the java tool from the SDK
	may have command line arguments
	to run you type java and the class file name (without its extension) on the command line
Java program	can be compiled on any platform that has a Java compiler
	can be run on any implementation of the Java Virtual Machine specification
	is portable because it is compiled into bytecode that can run on any computer with a Java Virtual Machine
	is usually slower than native code
	is executed by a Java Virtual Machine
	must be readable by humans
	runs on a Java platform
	should follow consistent guidelines that make the program easy to read
	to run you may need platform-specific instructions

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