Java · Theory

Java Comments

Theory

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Java Comments

Comments are notes for humans. The compiler ignores them. Three styles: // one line, /* many lines */, /** javadoc */ for classes and methods.

Write why a tricky decision exists, not every obvious line. Don’t leave huge commented-out code forever — delete it or use git.

MCQ favourite — name all three styles. Nesting /* */ carelessly can break compilation.

Let's take this on the board with one tiny Main class — no extra files. Java Comments — comments are ignored by the compiler; only sum print runs. Start from main, go line by line, and stop at each print. That output is the proof for Comments.

Exam tip

Name //, /* */, and /** */ in one breath.

Example

// Java Comments
public class Main {
  public static void main(String[] args) {
    // This is a single-line comment
    int sum = 2 + 3; /* inline note */
    System.out.println(sum);
  }
}

Java Comments — comments are ignored by the compiler; only sum print runs.

Short notes

DefComments are notes for humans. Compiler ignores them.
Rule// one line. /* many lines */. /** javadoc */.
RememberExplain why, not every obvious line.
TrapNested /* */ can break compile.

Java · Theory

Java Comments

← All stacks

Theory

24/270

Java Comments

Comments are notes for humans. The compiler ignores them. Three styles: // one line, /* many lines */, /** javadoc */ for classes and methods.

Write why a tricky decision exists, not every obvious line. Don’t leave huge commented-out code forever — delete it or use git.

MCQ favourite — name all three styles. Nesting /* */ carelessly can break compilation.

Exam tip

Name //, /* */, and /** */ in one breath.

Example

// Java Comments
public class Main {
  public static void main(String[] args) {
    // This is a single-line comment
    int sum = 2 + 3; /* inline note */
    System.out.println(sum);
  }
}

Java Comments — comments are ignored by the compiler; only sum print runs.

Short notes

DefComments are notes for humans. Compiler ignores them.
Rule// one line. /* many lines */. /** javadoc */.
RememberExplain why, not every obvious line.
TrapNested /* */ can break compile.

Java Comments

Example

Short notes

Questions

Java Comments

Example

Short notes

Questions