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();  
        }  
}