If you've spent any time searching the web for a "php to java," you are no doubt familiar with the name "numiton". A stackoverflow question concerning it is among the top results, but when you visit their website, it is not there.
There is a nice article about it in DZone by its creator, Robert Enyedi, as well as some advanced projects released on SourceForge, like "nBB2", a translation of the popular phpBB forum software.
The SourceForge site is still active, but for some reason, the only code released is a binary file. Since the license is listed as GPL, it is fair to run it through a decompiler.
Looks pretty advanced, given that the type inferences appear to have been all made. It is not clear, however, to what degree this is an automated conversion, and to what degree manual. The examples posted by RuntimeConverter are all without exception fully automated. It is probably fair to say that it would be completely impossible to achieve this level of type inference and have the program work.
Another interesting observation is that the code sizes are not very large - somehow nBB2 has only 3.1 MB of Java sources, while nwp (wordpress), has 3.9 MB. Wordpress is now 23 MB unzipped, and 11.07 MB if you count only .php files. Thats a 3x difference in size, so if the conversion was manual, whatever happened between now and 2013 is completely lost on the nBB2 project.
So what happened to numiton? The last post on their news page (viewed via archive), was on Sep 14, 2009. The website went offline, it seems, around January 09, 2015, judging by the IIS page in the wayback machine. Robert Enyedi lists on his LinkedIn page that he last worked at Numiton in March of 2010. After that, he is listed as a "Sr. Research Software Engineer" at IBM.
So there a the possible theory - "did IBM purchase numiton"? It definitely seems like it would be in their interest to purchase a php -> java converter, but there is no news anywhere. Do they have a secret php -> java converter that they use?
IBM actually has a number of php solutions, including Project Zero (wikipedia). It is important to note here how different these solutions are from the Runtime Converter, in that they "run php on a JVM" rather than do anything that resembles a conversion. Nevertheless, the point is that they made no secret of their project.
Another possibility was Microsoft, who has a PHP -> Java "Migration Assistant" , but it was developed in 2003, a full 5 years before numiton.
Finally, there has been some new development. Just in the past month, after 3 years of absence, the wayback machine registered an entry for numiton (two actually) - showing the old site from 2009. So looks like they were not purchased after all. The archive results from 2014 also show that the project did not change ownership, it just stopped operating.
So what really happened to numition? No doubt numiton attracted attention for the quality of its architect and developer, who proceeded to take a senior position at IBM and later eBay. It is also significant that numiton was located in Bucharest, Romania. The transition from startup founder in Romania to a senior developer at a major U.S. company is no doubt a significant success for numiton's founder. Maintaining the numiton website then, was probably not worth it.
It is worth noting that, while not much is known about numiton due to its secret demise, it probably did not reach the stage of converting and running advanced software without manual intervention.