The polco.callback.hdf5 package contains callback and factory classes to produce HDF5 output files (.mat files).

Note that the HDF5 Java library contains native methods. Hence, you need to download the appropriate native library for hdf-java (usually a .dll or .so file). The location path of the native library must be specified by setting the java.library.path system property:

java -Djava.library.path=PATH_TO_HDF_LIB ...

For details about the HDF5 format, see http://www.hdfgroup.org.