drools engine use decision table

Prerequisite preparation: Java virtual machine
Drools core library
Junit4.0 or above
rules Excel template table (create the content of the following picture into Excel)
The typical usage is to create KnowledgeBase based on excel, and then throw it to session execution, the parameters of execution and the results are inside params

package com.xxx.yyyy;
  2
  3 import java.io.File;
  4 import java.io.FileInputStream;
  5 import java.io.InputStream;
  6 import java.util.Arrays;
  7 import java.util.Collection;
  8 import java.util.HashMap;
  9 import java.util.Map;
10 import junit.framework.Assert;
11 import org.drools.KnowledgeBase;
12 import org.drools.KnowledgeBaseFactory;
13 import org.drools.builder.DecisionTableConfiguration;
14 import org.drools.builder.DecisionTableInputType;
15 import org.drools.builder.KnowledgeBuilder;
16 import org.drools.builder.KnowledgeBuilderFactory;
17 import org.drools.builder.ResourceType;
18 import org.drools.definition.KnowledgePackage;
19 import org.drools.io.ResourceFactory;
20 import org.drools.runtime.StatelessKnowledgeSession;
21 import org.junit.Test;
22 import org.junit.runner.RunWith;
23 import org.junit.runners.Parameterized;
24 import org.junit.runners.Parameterized.Parameters;
25
26 @RunWith(Parameterized. class )
27 public class IsP4PTest
28 {
29      private IsP4P param;
30
31      private String extected;
32
33      public IsP4PTest(IsP4P param, String extected)
34      {
35          this .param = param;
36          this .extected = extected;
37      }
38 public Map<String, Object> getParams()
39          {
40              Map<String, Object> params = new HashMap<String, Object>();
41
42              params.put("productLine", productLine);
43              params.put("productType", productType);
44              params.put("playType", playType);
45
46              return params;
47          }
48 public void testExcel(String fileName, Map<String, Object> params)
49              throws Exception
50      {
51          System.out.println("---------------begin------------------------");
52
53          DecisionTableConfiguration dtableconfiguration = KnowledgeBuilderFactory
54                  .newDecisionTableConfiguration();
55 dtableconfiguration.setInputType(DecisionTableInputType.XLS);
56          final KnowledgeBuilder kbuilder = KnowledgeBuilderFactory
57                  .newKnowledgeBuilder();
58 File file = new File(
59                  "F:\\juny.qu\\rule_workspace\\com.deppon.rules\\src\\main\\java\\com\\xxx\\yyyy\\"
60                          + fileName);
61          InputStream is = new FileInputStream(file);
62 kbuilder.add(ResourceFactory.newInputStreamResource(is, "UTF-8"),
63                  ResourceType.DTABLE);
64          if (kbuilder.hasErrors())
65          {
66              System.out.println(kbuilder.getErrors().toString());
67          }
68 Collection<KnowledgePackage> pkgs = kbuilder.getKnowledgePackages();
69          KnowledgeBase kbase = KnowledgeBaseFactory.newKnowledgeBase();
70          kbase.addKnowledgePackages(pkgs);
71
72 StatelessKnowledgeSession ksession = kbase
73                  .newStatelessKnowledgeSession();
74          ksession.execute(Arrays.asList( new Object[] { params }));
75
76 System.out.println("---------------end------------------------");
77 }
78
79
80 @Parameters
81      public static Collection<?> contructData()
82      {
83 return Arrays.asList( new Object[][] {
84                  { new IsP4P("搜索推广", "true", "null"), "true" },



         testExcel("ka/isP4P.xls", params);
96          Assert.assertEquals(extected, params.get("isP4P"));
97      }
98 }
99
100

1 package com.xxx.yyyy;
2
3 import java.io.File;
4 import java.io.FileInputStream;
5 import java.io.FileNotFoundException;
6 import java.io.InputStream;
7
8 import org.drools.decisiontable.InputType;
9 import org.drools.decisiontable.SpreadsheetCompiler;
10 import org.junit.Test;
11
12 public class SpreadsheetCompilerTest {
13
14 @Test
15     public void compile() throws FileNotFoundException{
16         //File file = new File("F:\\juny.qu\\rule_workspace\\com.deppon.rules\\src\\main\\java\\com\\xxx\\yyyy\\ka\\isP4P.xls");
17         //File file = new File("F:\\collections_study\\规则引擎系统开发小组\\规则引擎doc\\02开发\\06-详细设计\\增值服务折扣测试1.xls");
18         File file = new File("F:\\rules.xlsx");
19
20         InputStream is = new FileInputStream(file);
21
22         SpreadsheetCompiler converter = new SpreadsheetCompiler();
23         String drl = converter.compile(is, InputType.XLS); //--------exception here--------
24         System.out.println("\n\n" + drl);
25
26     }
27
28 }

运行结果如下： package rule_table;

//generated from Decision Table
import java.util.*;
// rule values at B22, header at B17
rule "ContractP4P_22"
when
$constract:java.util.HashMap($constract.get("productLine")=="搜索推广")
$constract.get("productType")=="true"
$constract.get("playType")=="null"
then
$constract.put("isP4P","true");
end
// rule values at B23, header at B17
rule "ContractP4P_23"
when
$constract.get("playType")=="null"
then
$constract.put("isP4P","true");
end
// rule values at B24,header at B17
rule "ContractP4P_24"
when
$constract:java.util.HashMap($constract.get("productLine")=="掘金推广")
$constract.get("productType")=="true"
$constract.get("playType")=="非轮播"
then
$constract.put("isP4P","false");
end
// rule values at B25, header at B17
rule "ContractP4P_25"
when
$constract:java.util.HashMap($constract.get("productLine")=="其他")
$constract.get("productType")=="false"
$constract.get("playType")=="其他"
then
$constract.put("isP4P","other");
end

When to Consider Using a Rule Sheet

如果规则可以表示成 templates+data(模板＋数据),可以考虑使用 decision tables。在决策表的每一行，采集数据和模板一起生成规则。使用基于决策表的Spreadsheet的API在Drools-decisiontables模块中。只有一个类：SpreadsheetCompiler. 这个类可以操作各种格式的Spreadsheet，并生成DRL规则（然后就可以常规的方式使用）。


一个典型的规则表的格式


 
决策表中的关键字说明：

drools engine use decision table

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