title: how to generate javadoc for multiple modules
body: <p>I'm trying to create javadoc (jdk11) for multiple modules in a single document.</p>
  
  <p>I tried to do it like this.</p>
  
  <p>The file/directory structure is:</p>
  
  <pre><code>workspace
      doc
      maths
          src
              main
                  java
                      net.virtualpsyclab.maths
                          net
                              virtualpsyclab
                                  maths
                                      lib
                                          *.java
                      module-info.java
      genutils
          src
              main
                  java
                      net.virtualpsyclab.genutilsm
                          net
                              virtualpsyclab
                                  genutilsm
                                      *.java
                      module-info.java
  module-info.java
  jdocOptions.txt
  files.lst
  </code></pre>
  
  <p>jdocOptions.txt contains:</p>
  
  <pre><code>-d doc
  --module-source-path .;genutils\src\main\java\net.virtualpsyclab.genutilsm;maths\src\main\java\net.virtualpsyclab.maths
  --module workspace,net.virtualpsyclab.genutilsm,net.virtualpsyclab.maths
  -verbose
  -overview overview.html
  </code></pre>
  
  <p><p>
  and files.lst lists all the *.java files.</p>
  
  <p><p>
  The three module-info.java files contain:</p>
  
  <pre><code>workspace\module-info.java
  module workspace{
      requires net.virtualpsyclab.genutilsm;
      requires net.virtualpsyclab.maths;
  }
  
  workspace\genutils\src\main\java\net.virtualpsyclab.genutilsm\module-info.java
  module net.virtualpsyclab.genutilsm{
      exports net.virtualpsyclab.genutilsm;
  }
  
  workspace\maths\src\main\java\net.virtualpsyclab.maths\module-info.java
  module net.virtualpsyclab.maths{
      exports net.virtualpsyclab.maths.lib;
  }
  </code></pre>
  
  <p><p>
  I want the documentation for the modules net.virtualpsyclab.genutilsm and net.virtualpsyclab.maths to appear in the directory workspace\doc and I run the command:</p>
  
  <pre><code>javadoc @jdocOptions.txt @files.lst 
  </code></pre>
  
  <p>from the directory workspace and I see all of the source files apparently being processed e.g. :</p>
  
  <pre><code>Loading source file c:\Users\Admin\workspace\maths\src\main\java\net.virtualpsyclab.maths\net\virtualpsyclab\maths\lib\NDieDistribution.java...
  [parsing started SimpleFileObject[C:\Users\Admin\workspace\maths\src\main\java\net.virtualpsyclab.maths\net\virtualpsyclab\maths\lib\NDieDistribution.java]]
  [parsing completed 0ms]
  </code></pre>
  
  <p>but then it all ends badly with "javadoc: error - module workspace not found."</p>
  
  <p><p>
  Any help on what I've got wrong here greatly appreciated.</p>