[bug修复] JsonUtil.toBean泛型数组类型丢失

hutool-core/src/main/java/cn/hutool/core/lang/reflect/ActualTypeMapperPool.java

@@ -2,8 +2,10 @@ package cn.hutool.core.lang.reflect;
 
 import cn.hutool.core.convert.Convert;
 import cn.hutool.core.map.WeakConcurrentMap;
+import cn.hutool.core.util.ArrayUtil;
 import cn.hutool.core.util.TypeUtil;
 
+import java.lang.reflect.GenericArrayType;
 import java.lang.reflect.ParameterizedType;
 import java.lang.reflect.Type;
 import java.lang.reflect.TypeVariable;
@@ -57,6 +59,22 @@ public class ActualTypeMapperPool {
 		return result;
 	}
 
+	public static Type getActualType(Type type, GenericArrayType genericArrayType) {
+		final Map<Type, Type> typeTypeMap = get(type);
+		Type actualType = typeTypeMap.get(genericArrayType);
+
+		if (actualType == null) {
+			Type componentType = typeTypeMap.get(genericArrayType.getGenericComponentType());
+			if (!(componentType instanceof Class<?>)) {
+				return null;
+			}
+			actualType = ArrayUtil.getArrayType((Class<?>) componentType);
+			typeTypeMap.put(genericArrayType, actualType);
+		}
+
+		return actualType;
+	}
+
 	/**
 	 * 获取指定泛型变量对应的真实类型<br>
 	 * 由于子类中泛型参数实现和父类（接口）中泛型定义位置是一一对应的，因此可以通过对应关系找到泛型实现类型<br>

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

@@ -3,12 +3,7 @@ package cn.hutool.core.util;
 import cn.hutool.core.lang.ParameterizedTypeImpl;
 import cn.hutool.core.lang.reflect.ActualTypeMapperPool;
 
-import java.lang.reflect.Field;
+import java.lang.reflect.*;
-import java.lang.reflect.Method;
-import java.lang.reflect.ParameterizedType;
-import java.lang.reflect.Type;
-import java.lang.reflect.TypeVariable;
-import java.lang.reflect.WildcardType;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
@@ -412,6 +407,9 @@ public class TypeUtil {
 		if (typeVariable instanceof TypeVariable) {
 			return ActualTypeMapperPool.getActualType(type, (TypeVariable<?>) typeVariable);
 		}
+		if (typeVariable instanceof GenericArrayType) {
+			return ActualTypeMapperPool.getActualType(type, (GenericArrayType) typeVariable);
+		}
 
 		// 没有需要替换的泛型变量，原样输出
 		return typeVariable;

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

@@ -4,8 +4,12 @@ import java.lang.reflect.Method;
 import java.lang.reflect.Type;
 import java.util.ArrayList;
 import java.util.List;
+
+import cn.hutool.core.lang.TypeReference;
 import lombok.Data;
+
 import static org.junit.jupiter.api.Assertions.*;
+
 import org.junit.jupiter.api.Test;
 
 public class TypeUtilTest {
@@ -97,4 +101,29 @@ public class TypeUtilTest {
 		private T level;
 	}
 
+
+	/**
+	 * fix github:issue#3873
+	 */
+	@Test
+	public void getActualTypeForGenericArrayTest() {
+		TypeReference<GenericArray<GenericArrayEle>> typeReference = new TypeReference<GenericArray<GenericArrayEle>>() {
+
+		};
+
+		Type levelType = TypeUtil.getFieldType(GenericArray.class, "level");
+		Type actualType = TypeUtil.getActualType(typeReference.getType(), levelType);
+		assertEquals(ArrayUtil.getArrayType(GenericArrayEle.class), actualType);
+	}
+
+	@Data
+	public static class GenericArray<T> {
+		private T[] level;
+	}
+
+	@Data
+	public static class GenericArrayEle {
+		private Long uid;
+	}
+
 }

hutool-json/src/test/java/cn/hutool/json/JSONUtilTest.java

@@ -4,7 +4,9 @@ import cn.hutool.core.collection.CollectionUtil;
 import cn.hutool.core.collection.ListUtil;
 import cn.hutool.core.date.DateUtil;
 import cn.hutool.core.lang.Console;
+import cn.hutool.core.lang.TypeReference;
 import cn.hutool.core.map.MapUtil;
+import cn.hutool.core.util.ArrayUtil;
 import cn.hutool.core.util.NumberUtil;
 import cn.hutool.json.test.bean.Price;
 import cn.hutool.json.test.bean.UserA;
@@ -290,4 +292,27 @@ public class JSONUtilTest {
 		final String jsonStr = JSONUtil.toJsonStr(userId);
 		assertEquals("{}", jsonStr);
 	}
+
+	/**
+	 * 类型引用数组泛型丢失
+	 */
+	@Test
+	public void issue3873Test() {
+		String json = "{\"results\":[{\"uid\":\"1\"}],\"offset\":0,\"limit\":20,\"total\":0}";
+		Results<Index> deserialize = JSONUtil.toBean(json, (new TypeReference<Results<Index>>() {
+		}), false);
+
+		assertEquals(Results.class, deserialize.getClass());
+		assertEquals(ArrayUtil.getArrayType(Index.class), deserialize.results.getClass());
+	}
+
+	@Data
+	public static class Results<T> {
+		public T[] results;
+	}
+
+	@Data
+	public static class Index {
+		public String uid;
+	}
 }