网友使用过程中的一个drools的复杂问题

 鄙人刚刚开始研究Drools，但看了些例子，仍然不知道怎么处理下面的业务： 

超市打折促销，某种商品（按照类别code）促销规则： 
   1.在指定日期区间内（比如1月1日-1月3日）， 
   2.买第1件按原价，第2件则价格打6折。第3件原价，第4件打6折... ... 

现在顾客推着购物车来消费，里面有很多种商品，其中上面促销的那种有5件，结果应该是3件原价，两件要打折。 

哪位大大提供个思路，怎么用drools来给顾客的购物票算总额。

 

由于之前使用的是excel规则表，我也使用excel规则表。

import Java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;
import java.util.Arrays;
import java.util.Collection;
import java.util.Map;


import org.drools.KnowledgeBase;
import org.drools.KnowledgeBaseFactory;
import org.drools.builder.DecisionTableConfiguration;
import org.drools.builder.DecisionTableInputType;
import org.drools.builder.KnowledgeBuilder;
import org.drools.builder.KnowledgeBuilderFactory;
import org.drools.builder.ResourceType;
import org.drools.definition.KnowledgePackage;
import org.drools.io.ResourceFactory;
import org.drools.runtime.StatelessKnowledgeSession;


public class KATestBase {
public void testExcel(String fileName, Map<String, Object> params)
throws Exception {
System.out.println("---------------begin------------------------");

DecisionTableConfiguration dtableconfiguration = KnowledgeBuilderFactory
.newDecisionTableConfiguration();
dtableconfiguration.setInputType(DecisionTableInputType.XLS);
final KnowledgeBuilder kbuilder = KnowledgeBuilderFactory
.newKnowledgeBuilder();
File file = new File("E:\\workspace\\epct\\rule\\src\\test\\resources\\"
+ fileName);
InputStream is = new FileInputStream(file);


//InputStream is = new ClassPathResource(fileName).getInputStream();
kbuilder.add(ResourceFactory.newInputStreamResource(is,"UTF-8"),
ResourceType.DTABLE);
if (kbuilder.hasErrors()) {
System.out.println(kbuilder.getErrors().toString());
}
Collection<KnowledgePackage> pkgs = kbuilder.getKnowledgePackages();
KnowledgeBase kbase = KnowledgeBaseFactory.newKnowledgeBase();
kbase.addKnowledgePackages(pkgs);


StatelessKnowledgeSession ksession = kbase
.newStatelessKnowledgeSession();
ksession.execute(Arrays.asList(new Object[] {params}));

System.out.println("---------------end------------------------");
}
}

 测试的子类如下：

import java.util.Arrays;
import java.util.Collection;
import java.util.HashMap;
import java.util.Map;


import junit.framework.Assert;


import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.Parameterized;
import org.junit.runners.Parameterized.Parameters;


@RunWith(Parameterized.class)  
public class DroolsTest extends KATestBase{
private KADest param;  
private String extected;  
     
public DroolsTest(KADest param,String extected) {  
       this.param = param;  
       this.extected = extected;  
}  
   
public static class KADest {
private String orderTime;
private String orderTotal;

public KADest(String orderTime, String orderTotal) {
this.orderTime = orderTime;
this.orderTotal = orderTotal;
}

public Map<String,Object> getParams(){
Map<String,Object> params = new HashMap<String,Object>();


params.put("orderTime", orderTime);
params.put("orderTotal", orderTotal);
params.put("discountTotal", 0);

return params;
}
} 
      
    @Parameters
    public static Collection<?> contructData(){  
        return Arrays.asList(new Object[][]{  
                {new KADest("2013-01-02 12:30:31","6"),"3"},
                {new KADest("2013-01-02 12:30:31","1"),"0"},
                {new KADest("2013-01-02 12:30:31","2"),"1"},
                {new KADest("2013-01-01 12:30:31","2"),"1"},
                {new KADest("2013-01-01 12:30:31","2"),"1"},
                {new KADest("2013-01-01 12:30:31","2"),"1"},
                {new KADest("2013-01-04 12:30:31","2"),"0"},
                {new KADest("2013-01-04 12:30:31","2"),"0"},
                {new KADest("2013-01-04 12:30:31","2"),"0"},
               });
    }  
    
    @Test
    public void testKaDest() throws Exception{
    Map<String,Object> params = new HashMap<String,Object>();
    params.putAll(param.getParams());
    System.out.println(params);
    super.testExcel("ka/drools.xls", params);
    System.out.println(params);
        Assert.assertEquals(extected, "" +params.get("discountTotal"));  
    }