javac

Compile a .java file

$ javac [path/to/file.java]

$ javac [path/to/file1.java path/to/file2.java ...]

$ javac [*.java]

$ javac -d [path/to/directory] [path/to/file.java]

javac [ options ] [ source files ] [ @listfiles ]

-classpath
    Specify where to find user class files and dependent libraries. Overrides the CLASSPATH environment variable if set.

-d
    Specify where to place generated class files.

-sourcepath
    Specify where to find input source files.

-source
    Specify the Java language version.

-target
    Generate class files that target a specific JVM version.

-deprecation
    Show the use of deprecated API elements.

-encoding
    Specify the character encoding used by source files.

-g
    Generate all debugging information.

-nowarn
    Disable warning messages.

-verbose
    Output messages about what the compiler is doing.

@
    Read options and filenames from file.

The javac command is the Java compiler. It compiles Java source code (.java files) into Java bytecode (.class files) that can be executed by the Java Virtual Machine (JVM). It's an essential tool for Java developers.
The compiler performs various checks during compilation, including syntax analysis, semantic analysis (type checking), and code generation. If any errors are found, javac will report them, preventing the generation of bytecode. The resulting .class files contain platform-independent bytecode, allowing Java applications to run on different operating systems that have a compatible JVM. javac supports a wide range of command-line options to control the compilation process, such as setting the classpath, specifying the target Java version, and generating debugging information. javac is part of the Java Development Kit (JDK).

The classpath setting can be tricky. Ensure it includes all necessary JAR files and directories.

A typical usage is: javac MyClass.java. This will compile MyClass.java and generate MyClass.class in the same directory. To specify output directory use -d: javac -d bin MyClass.java will generate the class in /bin directory.

javac provides detailed error messages, but they can sometimes be difficult to interpret. Understanding the error message is crucial for debugging.

javac was developed as part of the Java Development Kit (JDK) by Sun Microsystems (later acquired by Oracle). It has evolved with each new Java version to support new language features and improve performance. It's fundamental for building Java applications.

java(1), javadoc(1), jar(1)