| 提交 | 用户 | 时间 | ||
| e7c126 | 1 | package com.iailab.framework.common.util.spring; |
| H | 2 | |
| 3 | import cn.hutool.core.collection.CollUtil; | |
| 4 | import cn.hutool.core.map.MapUtil; | |
| 5 | import cn.hutool.core.util.ArrayUtil; | |
| 6 | import org.aspectj.lang.JoinPoint; | |
| 7 | import org.aspectj.lang.reflect.MethodSignature; | |
| 8 | import org.springframework.core.DefaultParameterNameDiscoverer; | |
| 9 | import org.springframework.core.ParameterNameDiscoverer; | |
| 10 | import org.springframework.expression.EvaluationContext; | |
| 11 | import org.springframework.expression.ExpressionParser; | |
| 12 | import org.springframework.expression.spel.standard.SpelExpressionParser; | |
| 13 | import org.springframework.expression.spel.support.StandardEvaluationContext; | |
| 14 | ||
| 15 | import java.lang.reflect.Method; | |
| 16 | import java.util.Collections; | |
| 17 | import java.util.List; | |
| 18 | import java.util.Map; | |
| 19 | ||
| 20 | /** | |
| 21 | * Spring EL 表达式的工具类 | |
| 22 | * | |
| 23 | * @author mashu | |
| 24 | */ | |
| 25 | public class SpringExpressionUtils { | |
| 26 | ||
| 27 | /** | |
| 28 | * Spring EL 表达式解析器 | |
| 29 | */ | |
| 30 | private static final ExpressionParser EXPRESSION_PARSER = new SpelExpressionParser(); | |
| 31 | /** | |
| 32 | * 参数名发现器 | |
| 33 | */ | |
| 34 | private static final ParameterNameDiscoverer PARAMETER_NAME_DISCOVERER = new DefaultParameterNameDiscoverer(); | |
| 35 | ||
| 36 | private SpringExpressionUtils() { | |
| 37 | } | |
| 38 | ||
| 39 | /** | |
| 40 | * 从切面中，单个解析 EL 表达式的结果 | |
| 41 | * | |
| 42 | * @param joinPoint 切面点 | |
| 43 | * @param expressionString EL 表达式数组 | |
| 44 | * @return 执行界面 | |
| 45 | */ | |
| 46 | public static Object parseExpression(JoinPoint joinPoint, String expressionString) { | |
| 47 | Map<String, Object> result = parseExpressions(joinPoint, Collections.singletonList(expressionString)); | |
| 48 | return result.get(expressionString); | |
| 49 | } | |
| 50 | ||
| 51 | /** | |
| 52 | * 从切面中，批量解析 EL 表达式的结果 | |
| 53 | * | |
| 54 | * @param joinPoint 切面点 | |
| 55 | * @param expressionStrings EL 表达式数组 | |
| 56 | * @return 结果，key 为表达式，value 为对应值 | |
| 57 | */ | |
| 58 | public static Map<String, Object> parseExpressions(JoinPoint joinPoint, List<String> expressionStrings) { | |
| 59 | // 如果为空，则不进行解析 | |
| 60 | if (CollUtil.isEmpty(expressionStrings)) { | |
| 61 | return MapUtil.newHashMap(); | |
| 62 | } | |
| 63 | ||
| 64 | // 第一步，构建解析的上下文 EvaluationContext | |
| 65 | // 通过 joinPoint 获取被注解方法 | |
| 66 | MethodSignature methodSignature = (MethodSignature) joinPoint.getSignature(); | |
| 67 | Method method = methodSignature.getMethod(); | |
| 68 | // 使用 spring 的 ParameterNameDiscoverer 获取方法形参名数组 | |
| 69 | String[] paramNames = PARAMETER_NAME_DISCOVERER.getParameterNames(method); | |
| 70 | // Spring 的表达式上下文对象 | |
| 71 | EvaluationContext context = new StandardEvaluationContext(); | |
| 72 | // 给上下文赋值 | |
| 73 | if (ArrayUtil.isNotEmpty(paramNames)) { | |
| 74 | Object[] args = joinPoint.getArgs(); | |
| 75 | for (int i = 0; i < paramNames.length; i++) { | |
| 76 | context.setVariable(paramNames[i], args[i]); | |
| 77 | } | |
| 78 | } | |
| 79 | ||
| 80 | // 第二步，逐个参数解析 | |
| 81 | Map<String, Object> result = MapUtil.newHashMap(expressionStrings.size(), true); | |
| 82 | expressionStrings.forEach(key -> { | |
| 83 | Object value = EXPRESSION_PARSER.parseExpression(key).getValue(context); | |
| 84 | result.put(key, value); | |
| 85 | }); | |
| 86 | return result; | |
| 87 | } | |
| 88 | ||
| 89 | } | |
