easy-rules 支持组合模式，但是一般我们看到的都是基于代码的，以下是一个基于yaml配置的组合模式rule 的试用
项目结构
- 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/maven-v4_0_0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>com.dalong</groupId> <artifactId>myruleapps</artifactId> <version>1.0-SNAPSHOT</version> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <encoding>UTF-8</encoding> <java.version>1.8</java.version> <maven.compiler.source>1.8</maven.compiler.source> <maven.compiler.target>1.8</maven.compiler.target> </properties> <build> <plugins> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-compiler-plugin</artifactId> <configuration> <source>8</source> <target>8</target> </configuration> </plugin> </plugins> </build> <packaging>jar</packaging> <dependencies> <dependency> <groupId>org.jeasy</groupId> <artifactId>easy-rules-core</artifactId> <version>3.4.0</version> </dependency> <dependency> <groupId>org.jeasy</groupId> <artifactId>easy-rules-mvel</artifactId> <version>3.4.0</version> </dependency> <dependency> <groupId>org.jeasy</groupId> <artifactId>easy-rules-spel</artifactId> <version>3.4.0</version> </dependency> <dependency> <groupId>org.slf4j</groupId> <artifactId>slf4j-simple</artifactId> <version>1.7.25</version> </dependency> </dependencies></project>- rule yaml 文件
rules-com.yml
---name: "1"description: "1"priority: 1compositeRuleType: "UnitRuleGroup"composingRules: - name: "2" description: "2" condition: "user.getAge()<29" priority: 2 actions: - "System.out.println(\"UnitRuleGroup rule2 \")" - name: "3" description: "3" condition: "user.name.length<10" priority: 3 actions: - "System.out.println(\"UnitRuleGroup rule3 \")"---name: "3"description: "3"condition: "user.name.length<50"priority: 3actions: - "System.out.println(\"default rule3 \")"代码集成
- 入口
注意引入了一个包含返回值的rule，具体参考https://www.cnblogs.com/rongfengliang/p/12688192.html
import org.jeasy.rules.api.*;import org.jeasy.rules.core.DefaultRulesEngine;import org.jeasy.rules.core.InferenceRulesEngine;import org.jeasy.rules.core.RuleBuilder;import org.jeasy.rules.mvel.MVELRuleFactory;import org.jeasy.rules.support.YamlRuleDefinitionReader;import org.mvel2.ParserContext;import java.io.FileNotFoundException;import java.io.FileReader;import java.util.HashMap;import java.util.Map;import static com.dalong.DecreaseTemperatureAction.decreaseTemperature;import static com.dalong.HighTemperatureCondition.itIsHot;import static com.dalong.AppendUserName.appendUserName;import static com.dalong.NameTooShort.nameTooShort;public class Launcher { public static void main(String[] args) throws Exception { app4(); } // 加载方式没变 private static void app4() throws Exception { MVELRuleFactory ruleFactory = new MVELRuleFactory(new YamlRuleDefinitionReader()); ParserContext context =new ParserContext(); context.addImport("UserService", UserService.class); Rules yamlRules = ruleFactory.createRules(new FileReader(Launcher.class.getClassLoader().getResource("rules-com.yml").getFile()),context); DefaultRulesEngine rulesEngine = new DefaultRulesEngine(); Facts facts = new Facts(); MyRule<User> rule = new MyRule<User>(); Map<Object,Object> userinfo = new HashMap<>(); userinfo.put("name2","dalong"); userinfo.put("age2",27); yamlRules.register(rule); User user =new User("dalong",27); user.setUserinfo(userinfo); facts.put("user",user); rulesEngine.registerRuleListener(new MyRulesListener()); rulesEngine.registerRulesEngineListener(new MyRuleEngineListener()); rulesEngine.fire(yamlRules, facts); if(rule.isExecuted()){ User userResult= rule.getResult(); System.out.println("result from final ruls"+userResult.toString()); } }}- 运行效果
四月 12, 2020 11:30:46 下午 com.dalong.MyRuleEngineListener beforeEvaluate信息: -----------------beforeEvaluate-----------------四月 12, 2020 11:30:46 下午 com.dalong.MyRuleEngineListener beforeEvaluate信息: org.jeasy.rules.api.Rules@78c03f1f [ { user : User{name='dalong', age=27, userinfo={name2=dalong, age2=27}} } ]四月 12, 2020 11:30:46 下午 com.dalong.MyRulesListener afterEvaluate信息: -----------------afterEvaluate-----------------四月 12, 2020 11:30:46 下午 com.dalong.MyRulesListener beforeExecute信息: -----------------beforeExecute-----------------四月 12, 2020 11:30:46 下午 com.dalong.MyRulesListener onSuccess信息: -----------------onSuccess-----------------四月 12, 2020 11:30:46 下午 com.dalong.MyRulesListener afterEvaluate信息: -----------------afterEvaluate-----------------四月 12, 2020 11:30:46 下午 com.dalong.MyRulesListener beforeExecute信息: -----------------beforeExecute-----------------四月 12, 2020 11:30:46 下午 com.dalong.MyRulesListener onSuccess信息: -----------------onSuccess-----------------四月 12, 2020 11:30:46 下午 com.dalong.MyRulesListener afterEvaluate信息: -----------------afterEvaluate-----------------四月 12, 2020 11:30:46 下午 com.dalong.MyRulesListener beforeExecute信息: -----------------beforeExecute-----------------四月 12, 2020 11:30:46 下午 com.dalong.MyRulesListener onSuccess信息: -----------------onSuccess-----------------四月 12, 2020 11:30:46 下午 com.dalong.MyRuleEngineListener afterExecute信息: -----------------afterExecute-----------------四月 12, 2020 11:30:46 下午 com.dalong.MyRuleEngineListener afterExecute信息: org.jeasy.rules.api.Rules@78c03f1f [ { user : User{name='dalong', age=27, userinfo={name2=dalong, age2=27}} } ]UnitRuleGroup rule2 UnitRuleGroup rule3 default rule3 my rule has been executedresult from final rulsUser{name='dalong', age=27, userinfo={name2=dalong, age2=27}}Process finished with exit code 0说明
其他组合模式的rule，配置一样
参考资料
来源：oschina
链接：https://my.oschina.net/u/4370783/blog/3231876