The class IloCplex offers a variety of ways to write information about a solution that it has found.

After solving, you can call the method IloCplex.writeMIPstart to write a MIP basis suitable for a restart. The file it writes is in MST format. That format is documented in the reference manual ILOG CPLEX File Formats.

The method IloCplex.exportModel writes the active model to a file. The format of the file depends on the file extension in the name of the file that your application passes as an argument to this method. A model exported in this way to a file can be read back into ILOG CPLEX by means of the method IloCplex.importModel. Both these methods are documented more fully in the reference manual of the Java API.