背景：

使用的基礎專案來自https://gitee.com/smell2/ruoyi-vue-activiti.git

引入drools的步驟如下：

一、建立ruoyi-drools模組

parent選ruoyi，點確定

二、在ruoyi-admin模組的pom.xml引入drools依賴和junit依賴

        <!-- drools-->
        <dependency>
            <groupId>com.ruoyi</groupId>
            <artifactId>ruoyi-drools</artifactId>
            <version>3.2
 
.0</version>
        </dependency>

        <!-- junit-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
        </dependency>

三、在ruoyi-admin模組配置drools

1.新建src/main/java/com/ruoyi/web/core/config/KiaSessionConfig.java，程式碼如下：

package com.ruoyi.web.core.config;

import org.kie.api.KieBase;
import org.kie.api.KieServices;
import org.kie.api.builder.*;
import org.kie.api.runtime.KieContainer;
import org.kie.api.runtime.KieSession;
import org.kie.internal.io.ResourceFactory;
import org.springframework.context.annotation.Bean;
 
import org.springframework.context.annotation.Configuration;
import org.springframework.core.io.Resource;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
import org.springframework.core.io.support.ResourcePatternResolver;

import java.io.IOException;


@Configuration
public class KiaSessionConfig {

    private static final String RULES_PATH = "rules/";

    @Bean
    public KieFileSystem kieFileSystem() throws IOException {
        KieFileSystem kieFileSystem = getKieServices().newKieFileSystem();
        for (Resource file : getRuleFiles()) {
            kieFileSystem.write(ResourceFactory.newClassPathResource(RULES_PATH + file.getFilename(), "UTF-8"));
        }
        return kieFileSystem;
    }

    private Resource[] getRuleFiles() throws IOException {

        ResourcePatternResolver resourcePatternResolver = new PathMatchingResourcePatternResolver();
        final Resource[] resources = resourcePatternResolver.getResources("classpath*:" + RULES_PATH + "**/*.*");
        return resources;

    }

    @Bean
    public KieContainer kieContainer() throws IOException {

        final KieRepository kieRepository = getKieServices().getRepository();
        kieRepository.addKieModule(new KieModule() {
            public ReleaseId getReleaseId() {
                return kieRepository.getDefaultReleaseId();
            }
        });

        KieBuilder kieBuilder = getKieServices().newKieBuilder(kieFileSystem());
        kieBuilder.buildAll();
        return getKieServices().newKieContainer(kieRepository.getDefaultReleaseId());

    }

    private KieServices getKieServices() {
        return KieServices.Factory.get();
    }

    @Bean
    public KieBase kieBase() throws IOException {
        return kieContainer().getKieBase();
    }

    @Bean
    public KieSession kieSession() throws IOException {
        return kieContainer().newKieSession();
    }
}

2.新建model目錄，並建立src/main/java/com/ruoyi/web/model/People.java，程式碼如下：

package com.ruoyi.web.model;

public class People {
    private int sex;

    private String name;

    private String drlType;

    public int getSex() {
        return sex;
    }

    public void setSex(int sex) {
        this.sex = sex;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getDrlType() {
        return drlType;
    }

    public void setDrlType(String drlType) {
        this.drlType = drlType;
    }
}

3.在resources目錄下建立rules資料夾，並在rules資料夾下建立drools規則檔案rule01.drl，程式碼如下：

import com.ruoyi.web.model.People;
dialect  "java"

rule "boy"
    when
        $p : People(sex == 1 && drlType == "people")
    then
        System.out.println($p.getName() + " is a boy");
end

rule "girl"
    when
        $p : People(sex == 0 && drlType == "people")
    then
        System.out.println($p.getName() + "is a girl");
end

4.新建單元測試類，src/test/java/com/ruoyi/test/DroolsJunitTest.java，程式碼如下：

package com.ruoyi.test;

import com.ruoyi.RuoYiApplication;
import com.ruoyi.web.model.People;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.kie.api.runtime.KieSession;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;

@RunWith(SpringRunner.class)
@SpringBootTest(classes = RuoYiApplication.class, webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT)
public class DroolsJunitTest {

    @Autowired
    private KieSession session;

    @Test
    public void people() {
        People people = new People();
        people.setName("drools");
        people.setSex(1);
        people.setDrlType("people");
        session.insert(people);//插入
        session.fireAllRules();//執行規則
    }
}

參考資料：

https://www.jb51.net/article/213244.htm

https://blog.csdn.net/qq_43466788/article/details/120916500