"package javax.xml.soap is declared in module java.xml.ws, which is not in the module graph"

Question

So I took the SOAP example at Working Soap client example , put it into a file SOAPClientSAAJ.java, and tried compiling it (Openjdk 9 on Debian):

t@h ~/javatest> javac SOAPClientSAAJ.java 
SOAPClientSAAJ.java:1: error: package javax.xml.soap is not visible
import javax.xml.soap.*;
                ^
  (package javax.xml.soap is declared in module java.xml.ws, which is not in the module graph)
1 error

After Googling some, I found out that compiling and running as

t@h ~/javatest> javac --add-modules java.xml.ws SOAPClientSAAJ.java
t@h ~/javatest> java --add-modules java.xml.ws SOAPClientSAAJ

works. See also this video for general background: https://www.youtube.com/watch?v=y8bpKYDrF5I&t=20m17s

Now, questions:

1. Shouldn't the compiler automatically add the module java.xml.ws ? (since it obviously knows it is needed) Is this a bug in javax.xml.soap ?
2. Why is the --add-modules option not documented in my man pages? (openjdk 9 in Debian)
3. What should I write in the .java file to automatically add the java.xml.ws module?

Answer 1

This is a result of the new Java 9 modules. The javax.xml.soap package is actually a Java EE package, and so now isn't visible. The current workaround is to either use the --add-modules, as you've done, or to modularize your code.

Modularizing your code requires restructuring it into modules, and including a module-info.java file that specifies the modules you're using. In your case, specifying java.se.ee would give access to all the EE modules.