Java Comments

Java Comments

Explanation. Comments are used to explain the purpose of code, its functionality, or any complex logic. They provide insights into the code's intention, making it easier for other developers (or your future self) to understand the code.

Readability: Comments can improve code readability by breaking down complex algorithms or explaining tricky parts of the code.

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Documentation: Comments serve as documentation for the codebase, helping developers understand how to use classes, methods, or functions

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Single-line Comments

• Single-line comments begin with // and continue until the end of the line. They are used to add brief explanations or annotations to specific lines of code.
• Single-line comments are ideal for providing short, concise explanations directly alongside the code they describe.

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Example

// This is a comment
System.out.println("Hello World");

This example uses a single-line comment at the end of a line of code:

Example

System.out.println("Hello World"); // This is a comment

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Java Multi-line Comments

• Multi-line comments begin with /* and end with */. They can span multiple lines and are often used for longer explanations, documentation, or temporarily disabling code blocks.
• Multi-line comments are suitable for providing detailed descriptions of methods, classes, or sections of code.

This example uses a multi-line comment (a comment block) to explain the code:

Example

/* The code below will print the words Hello World
to the screen, and it is amazing */
System.out.println("Hello World");

Single or multi-line comments?

It is up to you which you want to use. Normally, we use // for short comments, and /* */ for longer.

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