#vulnerable code 
                                @Test
    @Category(IntegrationTest.class)
    public void test() {
        try {
            Collection<VehicleRoutingProblemSolution> solutions = vra.searchSolutions();
            System.out.println(Solutions.bestOf(solutions).getCost());
            Assert.assertTrue(true);
        } catch (Exception e) {
            Assert.assertTrue(false);
        }
    } 
                            #location 6 
                            #vulnerability type NULL_DEREFERENCE
#fixed code
                                @Test
    @Category(IntegrationTest.class)
    public void test() {
        try {
            Collection<VehicleRoutingProblemSolution> solutions = vra.searchSolutions();
            Assert.assertTrue(true);
        } catch (Exception e) {
            Assert.assertTrue(false);
        }
    }