drools 整合springboot 整合 drools 测试例子--个税计算器规则

规则引擎，主要作用，就是将规则与java代码分离，可通过修改规则实时生效。让非java程序员，只要熟悉业务，也可以写规则。

规则引擎主要用在一些，打折、风控前置、后置、结算等模块地方。

新建一个droolsdemo的maven工程。

pom.xml

<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">
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starters</artifactId>
        <version>2.2.0.RELEASE</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.drools</groupId>
    <artifactId>DroolsDemo</artifactId>
    <version>1.0-SNAPSHOT</version>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-aop</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
        </dependency>
        <dependency>
            <groupId>commons-lang</groupId>
            <artifactId>commons-lang</artifactId>
            <version>2.6</version>
        </dependency>
        <!--drools规则引擎-->
        <dependency>
            <groupId>org.drools</groupId>
            <artifactId>drools-core</artifactId>
            <version>7.6.0.Final</version>
        </dependency>
        <dependency>
            <groupId>org.drools</groupId>
            <artifactId>drools-compiler</artifactId>
            <version>7.6.0.Final</version>
        </dependency>
        <dependency>
            <groupId>org.drools</groupId>
            <artifactId>drools-templates</artifactId>
            <version>7.6.0.Final</version>
        </dependency>
        <dependency>
            <groupId>org.kie</groupId>
            <artifactId>kie-api</artifactId>
            <version>7.6.0.Final</version>
        </dependency>
        <dependency>
            <groupId>org.kie</groupId>
            <artifactId>kie-spring</artifactId>
            <exclusions>
                <exclusion>
                    <groupId>org.springframework</groupId>
                    <artifactId>spring-tx</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.springframework</groupId>
                    <artifactId>spring-beans</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.springframework</groupId>
                    <artifactId>spring-core</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.springframework</groupId>
                    <artifactId>spring-context</artifactId>
                </exclusion>
            </exclusions>
            <version>7.6.0.Final</version>
        </dependency>
    </dependencies>
    <build>
        <finalName>${project.artifactId}</finalName>
        <resources>
            <resource>
                <directory>src/main/java</directory>
                <includes>
                    <include>**/*.xml</include>
                </includes>
                <filtering>false</filtering>
            </resource>
            <resource>
                <directory>src/main/resources</directory>
                <includes>
                    <include>**/*.*</include>
                </includes>
                <filtering>false</filtering>
            </resource>
        </resources>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

配置文件DroolsConfig.java

package com.drools.config;

import org.kie.api.KieBase;
import org.kie.api.KieServices;
import org.kie.api.builder.KieBuilder;
import org.kie.api.builder.KieFileSystem;
import org.kie.api.builder.KieRepository;
import org.kie.api.runtime.KieContainer;
import org.kie.internal.io.ResourceFactory;
import org.kie.spring.KModuleBeanFactoryPostProcessor;
import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
import org.springframework.core.io.support.ResourcePatternResolver;
import org.springframework.core.io.Resource;
import java.io.IOException;
/**
 * 规则引擎配置类
 */
@Configuration
public class DroolsConfig {
    //指定规则文件存放的目录
    private static final String RULES_PATH = "rules/";
    private final KieServices kieServices = KieServices.Factory.get();
    @Bean
    @ConditionalOnMissingBean
    public KieFileSystem kieFileSystem() throws IOException {
        System.setProperty("drools.dateformat","yyyy-MM-dd");
        KieFileSystem kieFileSystem = kieServices.newKieFileSystem();
        ResourcePatternResolver resourcePatternResolver = 
            new PathMatchingResourcePatternResolver();
        Resource[] files = 
            resourcePatternResolver.getResources("classpath*:" + RULES_PATH + "*.*");
        String path = null;
        for (Resource file : files) {
            path = RULES_PATH + file.getFilename();
            kieFileSystem.write(ResourceFactory.newClassPathResource(path, "UTF-8"));
        }
        return kieFileSystem;
    }
    @Bean
    @ConditionalOnMissingBean
    public KieContainer kieContainer() throws IOException {
        KieRepository kieRepository = kieServices.getRepository();
        kieRepository.addKieModule(kieRepository::getDefaultReleaseId);
        KieBuilder kieBuilder = kieServices.newKieBuilder(kieFileSystem());
        kieBuilder.buildAll();
        return kieServices.newKieContainer(kieRepository.getDefaultReleaseId());
    }
    
    @Bean
    @ConditionalOnMissingBean
    public KieBase kieBase() throws IOException {
        return kieContainer().getKieBase();
    }
    
    @Bean
    @ConditionalOnMissingBean
    public KModuleBeanFactoryPostProcessor kiePostProcessor() {
        return new KModuleBeanFactoryPostProcessor();
    }
}

入口控制类 RuleController.java

package com.drools.controller;

import javax.servlet.http.HttpServletRequest;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import com.drools.entity.Calculation;
import com.drools.service.RuleService;

@RestController
public class RuleController {
    @Autowired
    private RuleService ruleService;
    
    @RequestMapping("/calculate")
    public Calculation calculate(HttpServletRequest request){
        String wage = request.getParameter("wage");
        Calculation calculation = new Calculation();
        calculation.setWage(Double.parseDouble(wage));
        calculation = ruleService.calculate(calculation);
        System.out.println(calculation);
        return calculation;
    }
}

入参实体类 Calculation

package com.drools.entity;

public class Calculation {
    private double wage;//税前工资
    private double wagemore;//应纳税所得额
    private double cess;//税率
    private double preminus;//速算扣除数
    private double wageminus;//扣税额
    private double actualwage;//税后工资
    
    @Override
    public String toString() {
        return "Calculation{" +
                "wage=" + wage +
                ", actualwage=" + actualwage +
                ", wagemore=" + wagemore +
                ", cess=" + cess +
                ", preminus=" + preminus +
                ", wageminus=" + wageminus +
                '}';
    }

    public double getWage() {
        return wage;
    }

    public void setWage(double wage) {
        this.wage = wage;
    }

    public double getWagemore() {
        return wagemore;
    }

    public void setWagemore(double wagemore) {
        this.wagemore = wagemore;
    }

    public double getCess() {
        return cess;
    }

    public void setCess(double cess) {
        this.cess = cess;
    }

    public double getPreminus() {
        return preminus;
    }

    public void setPreminus(double preminus) {
        this.preminus = preminus;
    }

    public double getWageminus() {
        return wageminus;
    }

    public void setWageminus(double wageminus) {
        this.wageminus = wageminus;
    }

    public double getActualwage() {
        return actualwage;
    }

    public void setActualwage(double actualwage) {
        this.actualwage = actualwage;
    }
}

处理服务类RuleService

package com.drools.service;

import org.kie.api.KieBase;
import org.kie.api.runtime.KieSession;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import com.drools.entity.Calculation;

@Service
public class RuleService {
    @Autowired
    private KieBase kieBase;
    
    public void rule(){
        KieSession kieSession = kieBase.newKieSession();
        kieSession.fireAllRules();
        kieSession.dispose();
    }
    
    /**
     * @desc 个人所得税计算
     * @date 2020年6月18日 下午4:42:34
     * @param calculation
     * @return
     */
    public Calculation calculate(Calculation calculation){
        KieSession kieSession = kieBase.newKieSession();
        kieSession.insert(calculation);
        kieSession.fireAllRules();
        kieSession.dispose();
        return calculation;
    }
}

程序启动入口类DsApp

package com.drools;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class DsApp {
    public static void main(String[] args) {
        SpringApplication.run(DsApp.class,args);
    }
}

drools 规则文件  calculation.drl

package calculation
import com.drools.entity.Calculation

/**
    当前规则文件中的规则主要分为三类
    1、计算应纳税所得额有1个规则
    2、设置税率、速算扣除数有7个规则
    3、计算税后工资有1个规则
**/

//计算应纳税所得额
rule "计算应纳税所得额"
    salience 100
    date-effective "2011-09-01"
    no-loop true
    when
        $cal:Calculation(wage > 0)
    then
        double wagemore = $cal.getWage() - 3500;
        $cal.setWagemore(wagemore);
        update($cal);
end

//设置税率、速算扣除数
rule "设置税率，应纳税所得额<=1500"
    salience 90
    no-loop true
    activation-group "SETCess_Group"
    when
        $cal:Calculation(wagemore <= 1500)
    then
        $cal.setCess(0.03);//税率
        $cal.setPreminus(0);//速算扣除数
        update($cal);
end

rule "设置税率，应纳税所得额在1500至4500之间"
    salience 90
    no-loop true
    activation-group "SETCess_Group"
    when
        $cal:Calculation(wagemore <= 4500 && wagemore > 1500)
    then
        $cal.setCess(0.1);//税率
        $cal.setPreminus(105);//速算扣除数
        update($cal);
end


rule "个人所得税：设置税率-->>应纳税所得额在4500志9000之间"
    salience 90
    no-loop true
    activation-group "SETCess_Group"
    when
        $cal : Calculation(wagemore > 4500 && wagemore <= 9000)
    then
        $cal.setCess(0.2);
        $cal.setPreminus(555);
        update($cal);
end

rule "个人所得税：设置税率-->>应纳税所得额在9000志35000之间"
    salience 90
    no-loop true
    activation-group "SETCess_Group"
    when
        $cal : Calculation(wagemore > 9000 && wagemore <= 35000)
    then
        $cal.setCess(0.25);
        $cal.setPreminus(1005);
        update($cal);
end

rule "个人所得税：设置税率-->>应纳税所得额在35000至55000之间"
    salience 90
    no-loop true
    activation-group "SETCess_Group"
    when
        $cal : Calculation(wagemore > 35000 && wagemore <= 55000)
    then
        $cal.setCess(0.3);
        $cal.setPreminus(2755);
        update($cal);
end

rule "个人所得税：设置税率-->>应纳税所得额在55000至80000之间"
    salience 90
    no-loop true
    activation-group "SETCess_Group"
    when
        $cal : Calculation(wagemore > 55000 && wagemore <= 80000)
    then
        $cal.setCess(0.35);
        $cal.setPreminus(5505);
        update($cal);
end

rule "个人所得税：设置税率-->>应纳税所得额在80000以上"
    salience 90
    no-loop true
    activation-group "SETCess_Group"
    when
        $cal : Calculation(wagemore > 80000)
    then
        $cal.setCess(0.45);
        $cal.setPreminus(13505);
        update($cal);
end

rule "个人所得税：计算税后工资"
    salience 80
    when
        $cal : Calculation(wage > 0 && wagemore > 0 && cess > 0)
    then
        //扣税额
        double wageminus = $cal.getWagemore() * $cal.getCess() - $cal.getPreminus();
        double actualwage = $cal.getWage() - wageminus;
        $cal.setWageminus(wageminus);
        $cal.setActualwage(actualwage);
        System.out.println("-----税前工资："+$cal.getWage());
        System.out.println("-----应纳税所得额："+$cal.getWagemore());
        System.out.println("-----税率：" + $cal.getCess());
        System.out.println("-----速算扣除数：" + $cal.getPreminus());
        System.out.println("-----扣税额：" + $cal.getWageminus());
        System.out.println("-----税后工资：" + $cal.getActualwage());
end

总的目录结果如下：

启动运行。通过postmain访问。

加入参数wage

http://localhost:8080/calculate

 后台打印：

测试成功。

rule "计算应纳税所得额"
salience ----100 优先级
date-effective "2011-09-01" ----规则生效时间
no-loop true ----放死循环
when
----一定的规则条件
then
----这块纯粹的java代码。。。
end