UG: Document tools.jar not needed with Libdoc with Java+
Fixes
@@ -102,10 +102,14 @@ Java libraries with path
A Java test library implemented using the `static library API`_ can be
specified by giving the path to the source code file containing the
-library implementation. Additionally, :file:`tools.jar`, which is part
-of the Java JDK distribution, must be found from ``CLASSPATH`` when
-Libdoc is executed. Notice that generating documentation for Java
-libraries works only with Jython.
+library implementation. When using Java 9 or newer, documentation can be
+generated without external dependencies, but with older Java versions the
+:file:`tools.jar`, which is part of the Java JDK distribution, must be found
+from the ``CLASSPATH`` when Libdoc is executed. Notice that generating
+documentation for Java libraries works only with Jython.
+
+.. note:: Generating documentation without :file:`tools.jar` when using
+ Java 9 or newer is a new feature in Robot Framework 3.1.
Resource files with path
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