Unless specified all the contents of WikiJava are under the WikiJava:GFDL free license.
The license WikiJava uses grants free access to our content in the same sense as wikipedia:free software is licensed freely. This principle is known as wikipedia:copyleft. That is to say, WikiJava content can be copied, modified, and redistributed so long as the new version grants the same freedoms to others and acknowledges the authors of the WikiJava article used (a direct link back to the article satisfies our author credit requirement). WikiJava articles therefore will remain free under the GFDL and can be used by anybody subject to certain restrictions, most of which serve to ensure that freedom.
To fulfill the above goals, the text contained in WikiJava is copyrighted (automatically under the Berne Convention) by WikiJava contributors and licensed to the public under the GNU Free Documentation License (GFDL). The full text of this license is at Text of the GNU Free Documentation License. This text must not be changed.
The English text of the GFDL is the only legally binding document; what follows is our interpretation of the GFDL: the rights and obligations of users and contributors.
Contributors' rights and obligations
If you contribute material to WikiJava, you thereby license it to the public under the GFDL (with no invariant sections, front-cover texts, or back-cover texts). In order to contribute, you must be in a position to grant this license, which means that either
In the first case, you retain copyright to your materials. You can later republish and relicense them in any way you like. However, you can never retract the GFDL license for the copies of materials that you place here; these copies will remain under GFDL until they enter the Wikipedia:public domain.
In the second case, if you incorporate external GFDL materials, as a requirement of the GFDL, you need to acknowledge the authorship and provide a link back to the network location of the original copy.
Using copyrighted work from others
All works are copyrighted unless either they fall into the public domain or their copyright is explicitly disclaimed. If you use part of a copyrighted work under "fair use", or if you obtain special permission to use a copyrighted work from the copyright holder under the terms of our license, you must make a note of that fact (along with names and dates). It is our goal to be able to freely redistribute as much of WikiJava's material as possible, so original images and sound files licensed under the GFDL or in the Wikipedia:public domain are greatly preferred to copyrighted media files used under fair use.
Never use materials that infringe the copyrights of others. This could create legal liabilities and seriously hurt the project. If in doubt, write it yourself.
Note that copyright law governs the creative expression of ideas, not the ideas or information themselves. Therefore, it is legal to read an article or other work, reformulate the concepts in your own words, and submit it to WikiJava. However, it would still be unethical (but not illegal) to do so without citing the original as a reference. See Wikipedia:plagiarism and Wikipedia:fair use for discussions of how much reformulation is necessary in a general context.
Linking to copyrighted works
Since most recently-created works are copyrighted, almost any WikiJava article which cites its sources will link to copyrighted material. It is not necessary to obtain the permission of a copyright holder before linking to copyrighted material, just as an author of a book does not need permission to cite someone else's work in their bibliography. Likewise, Wikipedia is not restricted to linking only to GFDL-free or open-source content.
However, if you know that an external Web site is carrying a work in violation of the creator's copyright, do not link to that copy of the work. Knowingly and intentionally directing others to a site that violates copyright has been considered a form of contributory infringement. Linking to a page that illegally distributes someone else's work sheds a bad light on WikiJava and its editors.
If you suspect a copyright violation, you should at least bring up the issue on that page's discussion page. Others can then examine the situation and take action if needed. Some cases will be false alarms. For example, text that can be found elsewhere on the Web that was in fact copied from WikiJava in the first place is not a copyright violation – at least not on WikiJava's part.
If a page contains material which infringes copyright, that material – and the whole page, if there is no other material present – should be removed.
Reusers' rights and obligations
If you want to use WikiJava materials in your own books/articles/web sites or other publications, you can do so, but you have to follow the GFDL. If you are simply duplicating the WikiJava article, you must follow 2. VERBATIM COPYING|section two of the GFDL on verbatim copying.
If you create a derivative version by changing or adding content, this entails the following:
You may be able to partially fulfill the latter two obligations by providing a conspicuous direct link back to the WikiJava article hosted on this website. You also need to provide access to a transparent copy of the new text. However, please note that WikiJava makes no guarantee to retain authorship information and a transparent copy of articles. Therefore, you are encouraged to provide this authorship information and a transparent copy with your derived works.
Guideline to explicitly specify your license in a page
If you want to specify inside a page that its content go under the GPL license, you can simply use the following string in your page:
This will import generate in your page a text box as the following: