这篇文章主要讲解了“SpringBoot集成easy-rules规则引擎的流程是什么”，文中的讲解内容简单清晰，易于学习与理解，下面请大家跟着小编的思路慢慢深入，一起来研究和学习“SpringBoot集成easy-rules规则引擎的流程是什么”吧！
一、概述
通过将业务规则配置的配置文件中，可以精简代码，同时已于维护，当规则修改时，只需要修改配置文件即可。easy-rules是一个小巧的规则引擎，支持spring的SPEL表达式，同时还支持 Apache JEXL 表达式和 MVL 表达式。
二、项目中加入依赖
在项目的gradle中增加依赖关系。
build.gradle:
plugins {
id 'org.springframework.boot' version '3.0.5'
id 'io.spring.dependency-management' version '1.1.0'
id 'java'
}group = 'cn.springcamp'
version = '0.0.1-SNAPSHOT'
sourceCompatibility = '17'configurations {
compileOnly {
extendsFrom annotationProcessor
}
testCompileOnly {
extendsFrom testAnnotationProcessor
}
}repositories {
mavenCentral()
}dependencies {
implementation "org.springframework.boot:spring-boot-starter-json"
implementation 'org.springframework.boot:spring-boot-starter-validation'
implementation 'org.jeasy:easy-rules-core:4.1.0'
implementation 'org.jeasy:easy-rules-spel:4.1.0'
implementation 'org.jeasy:easy-rules-support:4.1.0'
annotationProcessor 'org.projectlombok:lombok'
testAnnotationProcessor 'org.projectlombok:lombok'
testImplementation "org.springframework.boot:spring-boot-starter-test"
testImplementation 'org.junit.vintage:junit-vintage-engine'
testImplementation 'org.junit.vintage:junit-vintage-engine'
}dependencyManagement {
imports {
mavenBom "org.springframework.cloud:spring-cloud-dependencies:2022.0.1"
}
}test {
useJUnitPlatform()
}
三、配置文件
示例程序将业务规则放到配置文件中，业务规则配置文件(demo-rule.yml)代码:
name: "age rule"
description: ""
priority: 1
condition: "#person.getAdult() == false"
actions:
- "T(java.lang.System).out.println(\"Shop: Sorry, you are not allowed to buy alcohol\")"
- "#person.setAdult(true)"
- "#person.setAge(18)"
---
name: "alcohol rule"
description: ""
priority: 1
condition: "#person.getAdult() == true"
actions:
- "T(java.lang.System).out.println(\"Shop: you are now allowed to buy alcohol\")"
配置文件中的规则通过 condition 进行配置，当满足规则时，会调用 actions 中配置的动作。
示例项目使用了spring的SPEL表达式进行规则配置，配置文件中配置了2个规则，第一个规则通过 person这个spring bean中的getAdult()判断是否满足规则，满足规则时调用三个方法。
在spring-boot本身的配置文件中 application.yml 配置规则文件：
rule:
skip-on-first-failed-rule: true
skip-on-first-applied-rule: false
skip-on-first-non-triggered-rule: true
rules:
- rule-id: "demo"
rule-file-location: "classpath:demo-rule.yml"
四、代码中对规则引擎进行配置
通过 RuleEngineConfig这个spring的配置类对规则引擎进行配置：
@Slf4j@EnableConfigurationProperties(RuleEngineConfigProperties.class)@Configurationpublic class RuleEngineConfig implements BeanFactoryAware { @Autowired(required = false) private List<RuleListener> ruleListeners; @Autowired(required = false) private List<RulesEngineListener> rulesEngineListeners; private BeanFactory beanFactory; @Bean public RulesEngineParameters rulesEngineParameters(RuleEngineConfigProperties properties) { RulesEngineParameters parameters = new RulesEngineParameters(); parameters.setSkipOnFirstAppliedRule(properties.isSkipOnFirstAppliedRule()); parameters.setSkipOnFirstFailedRule(properties.isSkipOnFirstFailedRule()); parameters.setSkipOnFirstNonTriggeredRule(properties.isSkipOnFirstNonTriggeredRule()); return parameters; } @Bean public RulesEngine rulesEngine(RulesEngineParameters rulesEngineParameters) { DefaultRulesEngine rulesEngine = new DefaultRulesEngine(rulesEngineParameters); if (!CollectionUtils.isEmpty(ruleListeners)) { rulesEngine.registerRuleListeners(ruleListeners); } if (!CollectionUtils.isEmpty(rulesEngineListeners)) { rulesEngine.registerRulesEngineListeners(rulesEngineListeners); } return rulesEngine; } @Bean public BeanResolver beanResolver() { return new BeanFactoryResolver(beanFactory); } @Bean public RuleEngineTemplate ruleEngineTemplate(RuleEngineConfigProperties properties, RulesEngine rulesEngine) { RuleEngineTemplate ruleEngineTemplate = new RuleEngineTemplate(); ruleEngineTemplate.setBeanResolver(beanResolver()); ruleEngineTemplate.setProperties(properties); ruleEngineTemplate.setRulesEngine(rulesEngine); return ruleEngineTemplate; } @Bean public RuleListener defaultRuleListener() { return new RuleListener() { @Override public boolean beforeEvaluate(Rule rule, Facts facts) { return true; } @Override public void afterEvaluate(Rule rule, Facts facts, boolean b) { log.info("-----------------afterEvaluate-----------------"); log.info(rule.getName() + rule.getDescription() + facts.toString()); } @Override public void beforeExecute(Rule rule, Facts facts) { log.info("-----------------beforeExecute-----------------"); log.info(rule.getName() + rule.getDescription() + facts.toString()); } @Override public void onSuccess(Rule rule, Facts facts) { log.info("-----------------onSuccess-----------------"); log.info(rule.getName() + rule.getDescription() + facts.toString()); } @Override public void onFailure(Rule rule, Facts facts, Exception e) { log.info("-----------------onFailure-----------------"); log.info(rule.getName() + "----------" + rule.getDescription() + facts.toString() + e.toString()); } }; } @Override public void setBeanFactory(BeanFactory beanFactory) throws BeansException { this.beanFactory = beanFactory; }}配置文件中配置了 ruleEngineTemplate这个spring bean，通过ruleEngineTemplate触发规则引擎的执行。
五、执行规则引擎
ruleEngineTemplate配置好后，我们可以在业务代码中执行规则引擎，处理配置文件中配置的业务规则：
最为演示，我们将规则引擎的执行代码放到了 Application 的 run 方法中，程序启动后立即执行规则引擎：
@SpringBootApplicationpublic class Application implements CommandLineRunner { @Autowired RuleEngineTemplate ruleEngineTemplate; public static void main(String[] args) { SpringApplication.run(Application.class, args); } @Override public void run(String... args) { Person person = new Person(); Facts facts = new Facts(); facts.put("person", person); ruleEngineTemplate.fire("demo", facts); }}程序执行后可以看到控制台里打印了 Shop: Sorry, you are not allowed to buy alcohol，这个内容对应的是我们在规则文件中的actions中配置的 "T(java.lang.System).out.println(\"Shop: Sorry, you are not allowed to buy alcohol\")"，说明规则成功执行了。
感谢各位的阅读，以上就是“SpringBoot集成easy-rules规则引擎的流程是什么”的内容了，经过本文的学习后，相信大家对SpringBoot集成easy-rules规则引擎的流程是什么这一问题有了更深刻的体会，具体使用情况还需要大家实践验证。这里是编程网，小编将为大家推送更多相关知识点的文章，欢迎关注！
