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实现了一个 Groovy 规则执行器，通过动态编译规则脚本并缓存执行对象（GroovyObject）来提升性能。主要流程如下：

1. 类名生成：通过规则内容的哈希值生成唯一类名（RuleScript_xxx）
2. 缓存机制：使用 ConcurrentHashMap 缓存已编译的规则对象
3. 动态编译：首次执行时生成 Groovy 类并实例化，后续直接从缓存读取对象
4. 规则执行：调用 evaluate 方法传入状态参数，返回整型结果

版本依赖

        <dependency><groupId>org.codehaus.groovy</groupId><artifactId>groovy</artifactId><version>3.0.19</version><scope>compile</scope></dependency>

 

1.第一种写法：首次执行加载到缓存，后续执行从缓存读取

package com.ruoyi.system.util;import com.ruoyi.common.core.utils.uuid.UUID;
import groovy.lang.GroovyClassLoader;
import groovy.lang.GroovyObject;import java.nio.charset.StandardCharsets;
import java.util.Collections;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;public class GroovyRuleExecutor3 {private static final GroovyClassLoader classLoader = new GroovyClassLoader();private static final Map<String, GroovyObject> CACHE = Collections.synchronizedMap(new LinkedHashMap<>(16, 0.75f, true) {@Overrideprotected boolean removeEldestEntry(Map.Entry<String, GroovyObject> eldest) {return size() > 100;}});private static String generateClassName(String rule) {String uuid = UUID.nameUUIDFromBytes(rule.getBytes(StandardCharsets.UTF_8)).toString();return "RuleScript_" + uuid.replace("-",  "");}public static int parseRule(String rule, String state) {try {System.out.println(CACHE.toString());return (int) CACHE.computeIfAbsent(rule,  k -> {long start = System.nanoTime();String className = generateClassName(rule);String script = "class " + className + " {\n" +"  int evaluate(String state) {\n" +"    " + rule + "\n" +"  }\n" +"}";synchronized (classLoader) {Class<?> clazz = classLoader.parseClass(script);try {GroovyObject instance = (GroovyObject) clazz.newInstance();return instance;} catch (InstantiationException | IllegalAccessException e) {throw new RuntimeException("实例化失败: " + e.getMessage(),  e);}}}).invokeMethod("evaluate", state);} catch (Exception e) {throw new IllegalArgumentException("规则执行失败: " + e.getMessage(),  e);}}public static void main(String[] args) {String rule = "if(state == '男') {return 1} else if(state == '女') {return 2} else {return 0}";long start = System.nanoTime();System.out.println(parseRule(rule,  "女"));  // 输出2long duration = System.nanoTime()  - start;System.out.println(" 首次执行结果: " + start + " (耗时: " + duration / 1_000_000 + "ms)");long start2 = System.nanoTime();System.out.println(parseRule(rule,  "男"));  // 输出1long duration2 = System.nanoTime()  - start2;System.out.println(" 首次执行结果: " + start2 + " (耗时: " + duration2 / 1_000_000 + "ms)");}
}

2.第二种写法，提前生成规则，项目启动加载规则，后续全部规则从缓存里面去，

package com.ruoyi.system.util;import groovy.lang.GroovyClassLoader;
import java.util.HashMap;
import java.util.Map;public class GroovyRuleExecutor2 {private static final GroovyClassLoader classLoader = new GroovyClassLoader();private static final Map<String, Class<?>> scriptCache = new HashMap<>();// 预编译并缓存脚本public static void loadScript(String scriptId, String code) {scriptCache.put(scriptId,  classLoader.parseClass(code));}// 安全执行方法public static Object execute(String scriptId, Map<String, Object> params) throws Exception {Class<?> scriptClass = scriptCache.get(scriptId);Object scriptInstance = scriptClass.newInstance();return scriptClass.getDeclaredMethod("execute",  Map.class).invoke(scriptInstance,  params);}public static void main(String[] args) throws Exception {String rule = "if(s.equals('0')){return '男'} else if(s.equals('2')){return 3}else if(s.equals('4')){return 5}else{return '哈哈'}";//String rule = "return new Date()";String script = "def execute(Map params) {  String s = params.get(\"s\").toString()" +"\n"+rule+"}";  // 替换为上述修正脚本loadScript("genderRule", script);Map<String, Object> input = new HashMap<>();input.put("s", "");System.out.println(execute("genderRule",  input));  // 明确抛出参数异常}
}