perf(core): 为ReflectUtil.getMethod新增细粒度方法查找缓存，提升高频反射调用性能

hutool-core/src/main/java/cn/hutool/core/util/ReflectUtil.java

@@ -36,6 +36,12 @@ public class ReflectUtil {
 	 * 方法缓存
 	 */
 	private static final WeakKeyValueConcurrentMap<Class<?>, Method[]> METHODS_CACHE = new WeakKeyValueConcurrentMap<>();
+	/**
+	 * 方法查找结果缓存（新增：细粒度缓存，避免重复遍历）
+	 * key: 方法查找键（类+是否忽略大小写+方法名+参数类型）
+	 * value: 查找到的Method
+	 */
+	private static final WeakKeyValueConcurrentMap<MethodLookupKey, Method> METHOD_LOOKUP_CACHE = new WeakKeyValueConcurrentMap<>();
 
 	// --------------------------------------------------------------------------------------------------------- Constructor
 
@@ -534,21 +540,25 @@ public class ReflectUtil {
 		if (null == clazz || StrUtil.isBlank(methodName)) {
 			return null;
 		}
-
-		Method res = null;
-		final Method[] methods = getMethods(clazz);
-		if (ArrayUtil.isNotEmpty(methods)) {
-			for (Method method : methods) {
-				if (StrUtil.equals(methodName, method.getName(), ignoreCase)
-					&& ClassUtil.isAllAssignableFrom(method.getParameterTypes(), paramTypes)
-					//排除协变桥接方法，pr#1965@Github
-					&& (res == null
-					|| res.getReturnType().isAssignableFrom(method.getReturnType()))) {
-					res = method;
+		// 优先从细粒度缓存查找
+		final MethodLookupKey key = new MethodLookupKey(clazz, ignoreCase, methodName, paramTypes);
+		return METHOD_LOOKUP_CACHE.computeIfAbsent(key, (lookupKey) -> {
+			// 缓存未命中时，执行原有的查找逻辑
+			Method res = null;
+			final Method[] methods = getMethods(clazz);
+			if (ArrayUtil.isNotEmpty(methods)) {
+				for (Method method : methods) {
+					if (StrUtil.equals(methodName, method.getName(), ignoreCase)
+						&& ClassUtil.isAllAssignableFrom(method.getParameterTypes(), paramTypes)
+						//排除协变桥接方法，pr#1965@Github
+						&& (res == null
+						|| res.getReturnType().isAssignableFrom(method.getReturnType()))) {
+						res = method;
+					}
 				}
 			}
-		}
-		return res;
+			return res;
+		});
 	}
 
 	/**
@@ -1193,4 +1203,40 @@ public class ReflectUtil {
 		}
 		return result;
 	}
+
+	/**
+	 * 方法查找键（用于细粒度缓存）
+	 * 用于唯一标识一次方法查找操作
+	 */
+	private static class MethodLookupKey {
+		private final Class<?> clazz;
+		private final boolean ignoreCase;
+		private final String methodName;
+		private final Class<?>[] paramTypes;
+
+		public MethodLookupKey(Class<?> clazz, boolean ignoreCase, String methodName, Class<?>[] paramTypes) {
+			this.clazz = clazz;
+			this.ignoreCase = ignoreCase;
+			this.methodName = methodName;
+			this.paramTypes = paramTypes;
+		}
+
+		@Override
+		public boolean equals(Object o) {
+			if (this == o) return true;
+			if (o == null || getClass() != o.getClass()) return false;
+			MethodLookupKey that = (MethodLookupKey) o;
+			return ignoreCase == that.ignoreCase &&
+				Objects.equals(clazz, that.clazz) &&
+				Objects.equals(methodName, that.methodName) &&
+				Arrays.equals(paramTypes, that.paramTypes);
+		}
+
+		@Override
+		public int hashCode() {
+			int result = Objects.hash(clazz, ignoreCase, methodName);
+			result = 31 * result + Arrays.hashCode(paramTypes);
+			return result;
+		}
+	}
 }

hutool-core/src/test/java/cn/hutool/core/util/ReflectUtilTest.java

@@ -412,4 +412,29 @@ public class ReflectUtilTest {
 		assertInstanceOf(LinkedList.class, dequeInstance);
 	}
 
+	/**
+	 * 验证getMethod缓存功能正常，结果与原逻辑一致
+	 */
+	@Test
+	public void testGetMethodWithCache() {
+		// 1. 正常方法查找验证
+		Method method1 = ReflectUtil.getMethod(String.class, "substring", int.class, int.class);
+		assertNotNull(method1);
+		assertEquals("substring", method1.getName());
+
+		// 2. 验证缓存命中：多次调用返回同一个对象
+		Method method2 = ReflectUtil.getMethod(String.class, "substring", int.class, int.class);
+		assertSame(method1, method2);
+
+		// 3. 忽略大小写场景验证
+		Method methodIgnoreCase1 = ReflectUtil.getMethodIgnoreCase(String.class, "SUBSTRING", int.class, int.class);
+		assertNotNull(methodIgnoreCase1);
+		Method methodIgnoreCase2 = ReflectUtil.getMethodIgnoreCase(String.class, "substring", int.class, int.class);
+		assertSame(methodIgnoreCase1, methodIgnoreCase2);
+
+		// 4. 边界场景：不存在的方法返回null
+		Method nullMethod = ReflectUtil.getMethod(String.class, "notExistMethod", String.class);
+		assertNull(nullMethod);
+	}
+
 }