Javadity is a Solidity to Java translator. It aims at generating a Java program that can be verified using the KeY tool.
It is highly recommended that you use Maven. To install Javadity, just type make grammar (to generate a Solidity parser) and then make (to build Javadity). Then you can get the jar into the folder target (the jar should be called javadity-X.Y-SNAPSHOT.jar).
Once compiled, you can easily run some test by doing make run EX=aSolidityFile.sol. Otherwise run java -jar javadity-X.Y-SNAPSHOT.jar --help for more information.