public OpenConfigConfigOfAssignmentHandler addAllocation(BigDecimal allocation) {
        modelObject.allocation(allocation);
        return this;
    }
@Test
    public void testAddAllocation() {
        // test Handler
        OpenConfigConfigOfAssignmentHandler config = new OpenConfigConfigOfAssignmentHandler(parent);

        // call addAllocation
        config.addAllocation(BigDecimal.valueOf(4));

        // expected ModelObject
        DefaultConfig modelObject = new DefaultConfig();
        modelObject.allocation(BigDecimal.valueOf(4));

        assertEquals("[NG]addAllocation:ModelObject(Allocation added) is not an expected one.\n",
                     modelObject, config.getModelObject());
    }