Drool实战系列(一)之入门程序

Drools官网地址为:https://www.drools.org/

maven环境

入门程序例子如下:

项目结构截图:

一、导入pom文件

<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>cn.drools</groupId>
  <artifactId>drools-demo</artifactId>
  <version>0.0.1-SNAPSHOT</version>

  <dependencies>
  	    <dependency>
        <groupId>org.drools</groupId>
        <artifactId>drools-core</artifactId>
        <version>6.2.0.Final</version>
    </dependency>
    <dependency>
        <groupId>org.drools</groupId>
        <artifactId>drools-compiler</artifactId>
        <version>6.2.0.Final</version>
    </dependency>
  </dependencies>
</project>

二、准备JavaBean

package com.test.bean;

public class Person {
     private String name;
        private int age;
        private String desc;  

        public Person(String name, int age) {
            this.name = name;
            this.age = age;
        }
        public String getName() {
            return name;
        }
        public void setName(String name) {
            this.name = name;
        }
        public int getAge() {
            return age;
        }
        public void setAge(int age) {
            this.age = age;
        }
        public String getDesc() {
            return desc;
        }
        public void setDesc(String desc) {
            this.desc = desc;
        }
        public String toString()
        {
            return "[name="+name+",age="+age+",desc="+desc+"]";
        }
    }  

三、在resource下建立rule文件夹编写drl文件

package com.person;  

import com.test.bean.Person;  

rule "boy"
    salience 1
    when
        $p : Person(age > 0);
    then
        $p.setDesc("少年");
        retract($p);
end  

rule "youth"
    salience 2
    when
        $p : Person(age > 12);
    then
        $p.setDesc("青年");
        retract($p);
end  

rule "midlife"
    salience 3
    when
        $p : Person(age > 24);
    then
        $p.setDesc("中年");
        retract($p);
end  

rule "old"
    salience 4
    when
        $p : Person(age > 60);
    then
        $p.setDesc("老年");
        retract($p);
end

四、编写kmodule.xml文件

<?xml version="1.0" encoding="UTF-8"?>
<kmodule xmlns="http://jboss.org/kie/6.0.0/kmodule">
    <kbase name="SimpleRuleKBase" packages="rule">
        <ksession name="simpleRuleKSession" default="true"/>
    </kbase>
</kmodule>

五、编写测试类

package com.test.bean;

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

public class Test {
     static KieSession getSession()
        {
            KieServices ks = KieServices.Factory.get();  

            KieContainer kc = ks.getKieClasspathContainer();  

            return kc.newKieSession("simpleRuleKSession");
        }
        public static void main(String[] args)
        {
            KieSession ks = getSession();  

            Person p1 = new Person("A", 68);
            Person p2 = new Person("B", 32);
            Person p3 = new Person("C", 18);
            Person p4 = new Person("D", 8);  

            System.out.println("before p1 : " + p1);
            System.out.println("before p2 : " + p2);
            System.out.println("before p3 : " + p3);
            System.out.println("before p4 : " + p4);  

            ks.insert(p1);
            ks.insert(p2);
            ks.insert(p3);
            ks.insert(p4);  

            int count = ks.fireAllRules();
            System.out.println("总执行了"+count+"条规则");
            System.out.println("after p1 : " + p1);
            System.out.println("after p2 : " + p2);
            System.out.println("after p3 : " + p3);
            System.out.println("after p4 : " + p4);
            ks.dispose();
        }
}