Add JavadocMissingLeadingAsterisk

commit-id:ec9e08c0

builder/src/main/resources/application.yml

@@ -1545,3 +1545,10 @@ rules:
         enabled: true
         source: CHECKSTYLE
         uri: https://checkstyle.sourceforge.io/config_whitespace.html#NoWhitespaceBeforeCaseDefaultColon
+    -
+        name: JavadocMissingLeadingAsterisk
+        parent: TREEWALKER
+        level: LAYOUT
+        enabled: true
+        source: CHECKSTYLE
+        uri: https://checkstyle.sourceforge.io/config_javadoc.html#JavadocMissingLeadingAsterisk

builder/src/main/resources/rules/JavadocMissingLeadingAsterisk.md

@@ -0,0 +1,50 @@
+
+Checks if the javadoc has leading asterisks on each line.
+
+The check does not require asterisks on the first line, nor on the last line if
+it is blank. All other lines in a Javadoc should start with *, including blank
+lines and code blocks. 
+
+Valid:
+````
+/**
+ * Valid Java-style comment.
+ *
+ * <pre>
+ *   int value = 0;
+ * </pre>
+ */
+class JavaStyle {} // ok
+
+/** Valid Scala-style comment.
+  * Some description here.
+  **/
+class ScalaStyle {} // ok
+
+/** **
+  * Asterisks on first and last lines are optional.
+  * */
+class Asterisks {} // ok
+
+/** No asterisks are required for single-line comments. */
+class SingleLine {} // ok
+````
+
+Invalid:
+````
+/** // violation on next blank line, javadoc has lines without leading asterisk.
+
+ */
+class BlankLine {}
+
+/** Wrapped
+    single-line comment */ // violation, javadoc has lines without leading asterisk.
+class Wrapped {}
+
+/**
+  * <pre>
+    int value; // violation, javadoc has lines without leading asterisk.
+  * </pre>
+  */
+class Code {}
+````