> ## Documentation Index
> Fetch the complete documentation index at: https://docs.syntblaze.com/llms.txt
> Use this file to discover all available pages before exploring further.
# Java Block Comment
A Java block comment (also known as a traditional comment) is a lexical construct used to embed non-executable text within source code. During the lexical analysis phase of compilation, the Java compiler partitions the character stream into `InputElement`s. Comments are discarded from the resulting token stream and are completely ignored during syntax parsing.
**Syntax**
A block comment begins with the forward-slash asterisk sequence `/*` and terminates with the asterisk forward-slash sequence `*/`. All characters enclosed between these delimiters are discarded.
```java theme={"dark"}
/*
This is a standard block comment.
It spans multiple lines.
*/
```
Because block comments are evaluated at the lexical level, they can also be placed inline within a statement, provided they do not split a single token.
```java theme={"dark"}
int total = baseValue + /* inline block comment */ tax;
```
**Lexical Rules and Constraints**
* **No Nesting:** Java does not support nested block comments. The compiler terminates the comment at the very first instance of `*/`. Attempting to nest them results in a syntax error because the compiler attempts to parse the trailing text as executable code.
```java theme={"dark"}
/* Outer comment
/* Inner comment */
This text is no longer commented and will cause a compilation error.
*/
```
* **String and Character Literals:** The `/*` and `*/` sequences hold no special lexical meaning when placed inside string (`" "`) or character (`' '`) literals. They are treated strictly as standard literal characters.
```java theme={"dark"}
String text = "This is not a /* comment */";
```
* **Unicode Escapes:** The Java compiler processes Unicode escapes (e.g., `\u002A` for `*` and `\u002F` for `/`) before evaluating comments. Consequently, Unicode representations of the delimiters will successfully initiate or terminate a block comment.
* **Differentiation from Javadoc:** While structurally similar, a block comment that begins with the exact sequence `/**` (a forward-slash followed by exactly two asterisks) is classified as a Javadoc comment. The compiler treats it as a standard block comment, but the `javadoc` tool parses it specifically for API documentation generation. The `javadoc` tool explicitly ignores comments that begin with three or more asterisks (e.g., `/***` or `/*******/`). This intentional behavior allows developers to use large asterisk banners as visual separators in the code without accidentally generating API documentation.
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