DefaultTaxPolicy.java

/*
 * Copyright 2011-2014 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package pl.com.bottega.ecommerce.sales.domain.invoicing.tax;

import java.math.BigDecimal;

import pl.com.bottega.ddd.annotations.domain.DomainPolicyImpl;
import pl.com.bottega.ecommerce.sales.domain.invoicing.Tax;
import pl.com.bottega.ecommerce.sales.domain.invoicing.TaxPolicy;
import pl.com.bottega.ecommerce.sales.domain.productscatalog.ProductType;
import pl.com.bottega.ecommerce.sharedkernel.Money;

/**
 * Sample Policy impl<br> 
 * 
 * @author Slawek
 *
 */
@DomainPolicyImpl
public class DefaultTaxPolicy implements TaxPolicy{
				
	
	@Override
	public Tax calculateTax(ProductType productType, Money net) {
		BigDecimal ratio = null;
		String desc = null;
		
		switch (productType) {
		case DRUG:
			ratio = BigDecimal.valueOf(0.05);
			desc = "5% (D)";
			break;
		case FOOD:
			ratio = BigDecimal.valueOf(0.07);
			desc = "7% (F)";
			break;
		case STANDARD:
			ratio = BigDecimal.valueOf(0.23);
			desc = "23%";
			break;
			
		default:
			throw new IllegalArgumentException(productType + " not handled");
		}
				
		Money tax = net.multiplyBy(ratio);
		
		return new Tax(tax, desc);
	}

}