SpringBoot之整合Drools

一、Drools是什么

Drools是一個易於訪問企業策略、易於調整以及易於管理的開源業務規則引擎，符合業內標准，速度快、效率高。業務分析師或審核人員可以利用它輕松查看業務規則，從而檢驗是否已編碼的規則執行所需的業務規則。

二、Drools有什么用

從我個人所待過的公司，其中做智能酒店這個項目時就用到規則引擎Drools，將它用於處理優惠劵規則。

三、SpringBoot整合Drools初步實戰

1.導入Maven依賴

<properties>
<drools.version>7.14.0.Final</drools.version>
</properties>

<!-- drools -->
<dependency>
    <groupId>org.drools</groupId>
    <artifactId>drools-compiler</artifactId>
    <version>${drools.version}</version>
</dependency>

2.編寫配置類

package com.springcloud.blog.admin.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();
    }
}

3.resources目錄新建rules目錄

4.新建實體

package com.springcloud.blog.admin.drools;

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;
    }
}

5.編寫規則文件

package com.springcloud.blog.admin.drools
import com.springcloud.blog.admin.drools.People
dialect  "java"

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

6.單元測試(只要正常輸出，表示整合是Ok的，接下來就可以任意應用了)

package com.springcloud.blog.base.controller.test.task;

import com.springcloud.blog.admin.BlogAdminApplication;
import com.springcloud.blog.admin.drools.People;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.kie.api.KieBase;
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 = BlogAdminApplication.class, webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT)
public class DroolsJunitTest {

    @Autowired
    private KieSession session;

    @Test
    public void people() {

        People people = new People();
        people.setName("YC");
        people.setSex(1);
        people.setDrlType("people");
        session.insert(people);//插入
        session.fireAllRules();//執行規則
    }


}

7.輸出結果

YC是男孩