drools程序开发，单机版。

dools程序开发，环境：java1.8，ecipse 版本Version: Neon.1a Release (4.6.1)Build id: 20161007-1200

 

pom.xml内容：

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>DroolTest</groupId>
  <artifactId>DroolTest</artifactId>
  <version>0.0.1-SNAPSHOT</version>

    <properties>
        <drools-version>7.0.0.Final</drools-version>
    </properties>

    <dependencies>
         <dependency>
         <groupId>junit</groupId>
         <artifactId>junit</artifactId>
         <version>4.12</version>
     </dependency>
        <dependency>
            <groupId>org.drools</groupId>
            <artifactId>drools-compiler</artifactId>
            <version>${drools-version}</version>
        </dependency>
    </dependencies>

  <packaging>war</packaging>
  <build>
    <sourceDirectory>src</sourceDirectory>
    <plugins>
      <plugin>
        <artifactId>maven-compiler-plugin</artifactId>
        <version>3.5.1</version>
        <configuration>
          <source>1.8</source>
          <target>1.8</target>
        </configuration>
      </plugin>
      <plugin>
        <artifactId>maven-war-plugin</artifactId>
        <version>3.0.0</version>
        <configuration>
          <warSourceDirectory>WebContent</warSourceDirectory>
        </configuration>
      </plugin>
    </plugins>
  </build>
</project>

 

===============================================

规则文件com/rules/Rules.drl内容：

package com.rules

import com.secbro.drools.model.Product
//这里可以写注释
rule Offer4Diamond
    when
        productObject : Product(type == Product.DIAMOND)
    then
        productObject.setDiscount(15);
    end
//这里可以写注释
rule Offer4Gold
    when
        productObject: Product(type == Product.GOLD)
    then
        productObject.setDiscount(25);
    end

==============================================

运行程序，虽然很老，但是在7.0版本中仍然可以正常运行。

package com.secbro.drools;

import com.secbro.drools.model.Product;

import org.junit.Test;
import org.kie.api.KieServices;
import org.kie.api.io.ResourceType;
import org.kie.api.runtime.KieContainer;
import org.kie.api.runtime.KieSession;
import org.kie.internal.KnowledgeBase;
import org.kie.internal.KnowledgeBaseFactory;
import org.kie.internal.builder.KnowledgeBuilder;
import org.kie.internal.builder.KnowledgeBuilderFactory;
import org.kie.internal.definition.KnowledgePackage;
import org.kie.internal.io.ResourceFactory;
import org.kie.internal.runtime.StatefulKnowledgeSession;

import java.util.Collection;

public class Drools5xTest {

    public static void main(String[] args) {
        Drools5xTest test = new Drools5xTest();
        test.oldExecuteDrools();
    }

    private void oldExecuteDrools() {

        KnowledgeBuilder kbuilder = KnowledgeBuilderFactory.newKnowledgeBuilder();
        kbuilder.add(ResourceFactory.newClassPathResource("com/rules/Rules.drl",
                this.getClass()), ResourceType.DRL);
        if (kbuilder.hasErrors()) {
            System.out.println(kbuilder.getErrors().toString());
        }

        Collection<KnowledgePackage> pkgs = kbuilder.getKnowledgePackages();
        // add the package to a rulebase
        KnowledgeBase kbase = KnowledgeBaseFactory.newKnowledgeBase();
        // 将KnowledgePackage集合添加到KnowledgeBase当中
        kbase.addKnowledgePackages(pkgs);

        StatefulKnowledgeSession ksession = kbase.newStatefulKnowledgeSession();
        Product product = new Product();
       // product.setType(Product.GOLD);
        product.setType(Product.DIAMOND);
        ksession.insert(product);
        ksession.fireAllRules();
        ksession.dispose();

        System.out.println("商品类型和折扣为： " + product.getType()
                + " is " + product.getDiscount()+"%");
    }
    
    @Test
    public void testRules() {
        // 构建KieServices
        KieServices ks = KieServices.Factory.get();
        KieContainer kieContainer = ks.getKieClasspathContainer();
        // 获取kmodule.xml中配置中名称为ksession-rule的session，默认为有状态的。
        KieSession kSession = kieContainer.newKieSession("ksession-rule");

        Product product = new Product();
        product.setType(Product.GOLD);

        kSession.insert(product);
        int count = kSession.fireAllRules();
        System.out.println("命中了" + count + "条规则！");
        System.out.println("商品" +product.getType() + "的商品折扣为" + product.getDiscount() + "%。");

    }
}

=====================================================

Product.java内容：

package com.secbro.drools.model;

public class Product {

    /**
     * 钻石
     */
    public static final String DIAMOND = "0";

    /**
     * 黄金
     */
    public static final String GOLD = "1";

    private String type;

    private int discount;

    public String getType() {
        return type;
    }

    public void setType(String type) {
        this.type = type;
    }

    public int getDiscount() {
        return discount;
    }

    public void setDiscount(int discount) {
        this.discount = discount;
    }
}
=======================================================

运行结果会输出：

商品类型和折扣为： 0 is 15%
 

=======================================================

修改规则文件Rules.drl，就可以看到不同的规则能产生不同的输出结果了。

=============================================================

drools新版本写法：7.17.0.Final版

package com.sample;

import org.kie.api.KieServices;
import org.kie.api.runtime.KieContainer;
import org.kie.api.runtime.KieSession;

/**
 * This is a sample class to launch a rule.
 */
public class DroolsTest {

    public static final void main(String[] args) {
        try {
            // load up the knowledge base
            KieServices ks = KieServices.Factory.get();
            KieContainer kContainer = ks.getKieClasspathContainer();
            KieSession kSession = kContainer.newKieSession("ksession-rules");

            // go !
            Message message = new Message();
            message.setMessage("Hello World");
            message.setStatus(Message.HELLO);
            kSession.insert(message);
            kSession.fireAllRules();
        } catch (Throwable t) {
            t.printStackTrace();
        }
    }

    public static class Message {

        public static final int HELLO = 0;
        public static final int GOODBYE = 1;

        private String message;

        private int status;

        public String getMessage() {
            return this.message;
        }

        public void setMessage(String message) {
            this.message = message;
        }

        public int getStatus() {
            return this.status;
        }

        public void setStatus(int status) {
            this.status = status;
        }

    }

}

=================================================

Sample.drl文件内容：

package com.sample
 
import com.sample.DroolsTest.Message;
 
rule "Hello World"
    when
        m : Message( status == Message.HELLO, myMessage : message )
    then
        System.out.println( myMessage );
        m.setMessage( "Goodbye cruel world" );
        m.setStatus( Message.GOODBYE );
        update( m );
end

rule "GoodBye"
    when
        Message( status == Message.GOODBYE, myMessage : message )
    then
        System.out.println( myMessage );
end

=================================================

kmodule.xml配置内容：

<?xml version="1.0" encoding="UTF-8"?>
<kmodule xmlns="http://jboss.org/kie/6.0.0/kmodule">
    <kbase name="rules" packages="rules">
        <ksession name="ksession-rules"/>
    </kbase>
    <kbase name="dtables" packages="dtables">
        <ksession name="ksession-dtables"/>
    </kbase>
    <kbase name="process" packages="process">
        <ksession name="ksession-process"/>
    </kbase>
</kmodule>

=================================================

7.17.0.Final版支持多种资源，rule规则，决策表DecisionTable（源文件居然是个xls？？？），流程定义文件bpmn

=================================================

sample.bpmn内容如下:

 

<?xml version="1.0" encoding="UTF-8"?>
<definitions id="Definition"
             targetNamespace="http://www.jboss.org/drools"
             typeLanguage="http://www.java.com/javaTypes"
             expressionLanguage="http://www.mvel.org/2.0"
             xmlns="http://www.omg.org/spec/BPMN/20100524/MODEL"
             xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://www.omg.org/spec/BPMN/20100524/MODEL BPMN20.xsd"
             xmlns:bpmndi="http://www.omg.org/spec/BPMN/20100524/DI"
             xmlns:dc="http://www.omg.org/spec/DD/20100524/DC"
             xmlns:di="http://www.omg.org/spec/DD/20100524/DI"
             xmlns:tns="http://www.jboss.org/drools">

  <process id="com.sample.bpmn.hello" tns:packageName="defaultPackage" name="Hello World" isExecutable="true" processType="Private">

    <!-- nodes -->
    <scriptTask id="_2" name="Hello" >
      <script>System.out.println("Hello World");</script>
    </scriptTask>
    <startEvent id="_1" />
    <endEvent id="_3" >
        <terminateEventDefinition/>
    </endEvent>

    <!-- connections -->
    <sequenceFlow id="_1-_2" sourceRef="_1" targetRef="_2" />
    <sequenceFlow id="_2-_3" sourceRef="_2" targetRef="_3" />

  </process>

  <bpmndi:BPMNDiagram>
    <bpmndi:BPMNPlane bpmnElement="com.sample.bpmn.hello" >
      <bpmndi:BPMNShape bpmnElement="_2" >
        <dc:Bounds x="96" y="16" width="80" height="48" />
      </bpmndi:BPMNShape>
      <bpmndi:BPMNShape bpmnElement="_1" >
        <dc:Bounds x="30" y="22" width="36" height="36" />
      </bpmndi:BPMNShape>
      <bpmndi:BPMNShape bpmnElement="_3" >
        <dc:Bounds x="210" y="22" width="36" height="36" />
      </bpmndi:BPMNShape>
      <bpmndi:BPMNEdge bpmnElement="_1-_2" >
        <di:waypoint x="66" y="40" />
        <di:waypoint x="96" y="40" />
      </bpmndi:BPMNEdge>
      <bpmndi:BPMNEdge bpmnElement="_2-_3" >
        <di:waypoint x="176" y="40" />
        <di:waypoint x="210" y="40" />
      </bpmndi:BPMNEdge>
    </bpmndi:BPMNPlane>
  </bpmndi:BPMNDiagram>

</definitions>

==============================================================

基本的套路是先定义规则或者决策表，然后定义流程引用规则或决策表。然后，输出流程结果。