If I wanted to create a commercial web-project (like e.g. facebook) with a Java backend (created with the Java SDK) which generates a "normal" HTML frontend, would I have to purchase a commercial license from SUN/Oracle?
Or does this only apply to applications written in Java which are directly being shipped to a customer?
no license fee is required in either case.
3rd party libraries may have their own licensing requirements.
http://java.sun.com/j2se/1.5.0/source_license.html
The binary JDK and JRE are available at no-fee from Sun (per terms of the BCL) for use with desktop personal computers. Both the JDK and JRE can be freely redistributed with value-add. JDK or JRE use for embedded devices and other computing environments may require a license fee from Sun.
There are two parts.
The JDK which is open source, and according to the JDK license is free to use :
A. Software Internal Use and Development License Grant. Subject to
the terms and conditions of this Agreement and restrictions and
exceptions set forth in the Software "README" file incorporated herein
by reference, including, but not limited to the Java Technology
Restrictions of these Supplemental Terms, Oracle grants you a
non-exclusive, non-transferable, limited license without fees to
reproduce internally and use internally the Software complete and
unmodified for the purpose of designing, developing, and testing your
Programs.
And the JRE part which can run such applications :
- LICENSE TO USE. Subject to the terms and conditions of this
Agreement, including, but not limited to the Java Technology
Restrictions of the Supplemental License Terms, Oracle grants you a
non-exclusive, non-transferable, limited license without license fees
to reproduce and use internally Software complete and unmodified for
the sole purpose of running Programs. Additional licenses for
developers and/or publishers are granted in the Supplemental License
Terms.
Between the two steps there is only one license, the one you put on your application.
You can develop your application without fees. And users can use your application without fees.
Ergo, you can use your own application without fees.
Resources :
The cross-section of Java software that you could use to create such an application is so broad that the answer depends entirely on the software you use. It is always necessary to check the terms of the licenses for your software.
Note that Oracle don't make the only JVM and that there are free open source Java server software stacks. Production of a Java application with any distribution model doesn't automatically imply a need to obtain a license from Oracle.
I contacted Oracle and a consultant explained it to me like this: