Those classes are intented for users dealing with SAT solvrs as a blackbox. Typical usage is the following:
    ISolver solver = SolverFactory.newMiniLearning();
    Dimacs parser = new Dimacs();
    
    try {
        parser.parseInstance("myfile.cnf",solver);    
        if (solver.solve()) {
    	    // SAT case
        } else {
    	    // UNSAT case
        }
    } catch (FileNotFoundException e) {
      // file not found
    } catch (ParseFormatException e) {
      // pbm in Dimacs format
    } catch (IOException e) {
      // Other IO Exception
    } catch (ContradictionException e) {
      // Trivial UNSAT case
    }