Make references optional for link and linkplain tags #13043
Description
Base on discussion at #12979
We need to update grammar for {@link}, {@linkplain} so their reference can be empty.
CLI:
$ cat Test1.java
class Test {
/**
* {@link}
*/
public void method(String a)
{
}
}
$ cat config1.xml
<?xml version="1.0"?>
<!DOCTYPE module PUBLIC
"-//Checkstyle//DTD Checkstyle Configuration 1.3//EN"
"https://checkstyle.org/dtds/configuration_1_3.dtd">
<module name = "Checker">
<property name="charset" value="UTF-8"/>
<module name="TreeWalker">
<module name="NonEmptyAtclauseDescription"/>
</module>
</module>
$ java -jar checkstyle-10.9.3-all.jar -c config1.xml Test1.java
Starting audit...
[ERROR] E:\Parse\Test1.java:4: Javadoc comment at column 11 has parse error.
Details: mismatched input '}' expecting {LEADING_ASTERISK, WS, NEWLINE} while
parsing JAVADOC_INLINE_TAG [NonEmptyAtclauseDescription]
Audit done.
Checkstyle ends with 1 errors.
Excepted:
Have no parse error.
$ javadoc -d doc Test1.java
Loading source file Test1.java...
Constructing Javadoc information...
Creating destination directory: "doc\"
Standard Doclet version 11.0.18
Building tree for all the packages and classes...
Generating doc\Test1.html...
Test1.java:6: warning: no @param for a
public void method(String a)
^
Generating doc\package-summary.html...
Generating doc\package-tree.html...
Generating doc\constant-values.html...
Building index for all the packages and classes...
Generating doc\overview-tree.html...
Generating doc\index-all.html...
Building index for all classes...
Generating doc\allclasses-index.html...
Generating doc\allpackages-index.html...
Generating doc\deprecated-list.html...
Building index for all classes...
Generating doc\allclasses.html...
Generating doc\allclasses.html...
Generating doc\index.html...
Generating doc\help-doc.html...
1 warning
LINK_LITERAL (WS | NEWLINE | LEADING_ASTERISK)+ reference (WS | NEWLINE)* ((WS | NEWLINE) description)?
LINKPLAIN_LITERAL (WS | NEWLINE | LEADING_ASTERISK)+ reference (WS | NEWLINE)* ((WS | NEWLINE) description)?