What are the Roles of Java Compiler and Interpreter?

In Java, a compiler and an interpreter are two tools that translate programs from high-level code to machine code. Both are essential for executing Java programs, but they work differently.

Java Compiler

A Java compiler translates the entire source code into bytecode (intermediate code) before execution. The bytecode is platform-independent and can be executed by the Java Virtual Machine (JVM).

• Operated using javac.exe from the command prompt.
• Generates bytecode (.class files).
• Performs syntax and type checking.
• Can add additional code if required.
• Requires more memory but produces faster execution.

Compiler Options:

• -help: it prints a summary of standard options.
• -version: returns the compiler information.
• -verbose: provides detailed compilation information.
• -nowarn: it is used to turn off warnings. 

Java Compiler: Step-by-Step Process

Roles of Java Compiler

• Scans the complete source code at once and highlights errors.
• Ensures correctness by checking syntax and type errors.
• Produces bytecode ready for execution.
• Adds additional necessary code automatically.

Java Interpreter

A Java interpreter (JVM) executes the bytecode line by line, translating it into native machine code at runtime.

• Converts bytecode into machine-specific code.
• Operates line by line.
• Stops execution if an error occurs on any line.
• Slower execution compared to compiler, but uses less memory.

Interpreter Options

• -version: displays interpreter version.
• -verbose: displays interpreter information.
• -help: displays interpreter options.

Java Interpreter: Step-by-Step Execution

Roles of Java Interpreter

• To convert the bytecode into the native code of the machine.
• This process is done line by line.
• If the error comes on any line, the process is stopped over there.

Compiler vs Interpreter in Java