What does the javac command do in Java?
The javac command reads source files that contain module, package and type declarations written in the Java programming language, and compiles them into class files that run on the Java Virtual Machine. The javac command can also process annotations in Java source files and classes. Source files must have a file name extension of .java.
Why does javac compile all Java files at the same time?
This allows the compiler to verify that they exist, figure out what methods they have, etc. javac is pretty sensitive to package names and classpaths. The easiest thing to do is to compile all three at the same time like so javac example/a.java example/b.java example/c.java.
How to compile and run Java program in CMD?
So that is how you compile and run a java program in cmd. You can also go through these material that is Java in depth lessons. Lot of things you need to understand in Java is covered there for beginners. You can compile any java source using javac in command line ; eg, javac CopyFile.java.
Which is the correct order to compile javac?
The order of source files specified on the command line or in an argument file is not important. javacwill compile the files together, as a group, and will automatically resolve any dependencies between the declarations in the various source files.
What does javac look for in the class path?
The class path is a sequence of directories (or zip files) which javac searches for classes not already defined in any of the files specified directly as command arguments. The compiler looks in the class path for both a source file and a class file, recompiling the source (and regenerating the class file) if it is newer.
How does javac know if a class file is out of date?
Search produces both a source file and a class file: javac determines whether the class file is out of date. If the class file is out of date, javac recompiles the source file and uses the updated class file. Otherwise, javac just uses the class file. By default, javac considers a class file out of date only if it is older than the source file.
How does javac search for a class file?
Search produces a source file but no class file: javac compiles the source file and uses the resulting class file. Search produces both a source file and a class file: javac determines whether the class file is out of date. If the class file is out of date, javac recompiles the source file and uses the updated class file.