Javadoc for local variables?

Question

Short question: Is it possible to create Javadoc for local variables? (I just want an explanation for my local variable when hovering over it in Eclipse) Thanks for any hint :-)

You can include variable description into method's JavaDoc comment — Aleksandr Kravets, May 16 '12 at 06:31
Sometime when you have to debug an other person code and local variables are messy, it would help. — Ced, Nov 20 '17 at 16:06

score 12 · Answer 1 · answered Mar 09 '15 at 11:11

12

It can be done using Annotations.

Create a simple annotation type such as the following:

@Retention(RetentionPolicy.SOURCE)
@Target(ElementType.LOCAL_VARIABLE)
@interface LocalVariableDocumentation {
    String value();
}

And use it on your local variable:

@LocalVariableDocumentation("A very important object!")
Object anImportantObject;

Eclipse will show the annotation in the tooltip.

answered Mar 09 '15 at 11:11

Elist

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What import is required for this? There is little to no documentation from search engines. – Richard Jessop Jan 20 '22 at 13:12

score 6 · Answer 2 · answered May 16 '12 at 06:27

6

No, it's not supported because JavaDoc generation will ignore it.

answered May 16 '12 at 06:27

nitind

19,089
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score 4 · Answer 3 · answered May 12 '12 at 18:31

4

The local variable should be declared a few lines above its usage. Just use regular comments if you need to. But more importantly, keep methods short, choose meaningful names for them, and declare them only when you need them. Most of the time, it's completely unnecessary to comment local variables.

Prefer

int numberOfBooks = books.size();

over

// the number of books
int n;
... // 50 lines of code
n = books.size();

answered May 12 '12 at 18:31

JB Nizet

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11

I agree it's unnecessary *most of the time*, but there are just things that are more complex to explain than number of books and such stuff, especially when doing more complex calculations etc. – stefan.at.kotlin May 12 '12 at 18:46

score 2 · Answer 4 · answered Sep 09 '16 at 11:34

2

The only way it's possible is with global variables. Local variables cannot be annotated with JavaDoc's.

answered Sep 09 '16 at 11:34

K. Raisor

21
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score 2 · Answer 5 · answered Nov 04 '16 at 23:37

2

Just make a link to your local variable

String someLocalVariable;
/**
 * This a local variable: {@link #someLocalVariable}
 */

answered Nov 04 '16 at 23:37

Harrison Kiang

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4

chrizdekok · Answer 6 · 2014-04-29T07:50:05.857

-3

Yes it's possible. Just make a regular javadoc comment above the variable.

public class ExampleClass {
    /** A really cool variable */
    int localVariable;

    ...

Now you can hover above the variable in the code further down and the comment will be shown.

edited Apr 29 '14 at 07:50

answered Apr 29 '14 at 07:02

chrizdekok

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I too thought this was the case. Maybe it was an older version of Eclipse. – jonS90 Sep 06 '17 at 19:35

Javadoc for local variables?

6 Answers6

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