fix bug

CHANGELOG.md

@@ -3,7 +3,7 @@
 
 -------------------------------------------------------------------------------------------------------------
 
-# 5.7.10 (2021-08-19)
+# 5.7.10 (2021-08-22)
 
 ### 🐣新特性
 * 【core   】     增加NamingCase类
@@ -18,6 +18,7 @@
 * 【core   】     修复MapUtil.sort比较器不一致返回原map的问题（issue#I46AQJ@Gitee）
 
 ### 🐞Bug修复
+* 【core   】     修复JSONSupport默认循环引用导致的问题（issue#1779@Github）
 
 -------------------------------------------------------------------------------------------------------------
 

hutool-json/src/main/java/cn/hutool/json/JSONConverter.java

@@ -85,10 +85,30 @@ public class JSONConverter implements Converter<JSON> {
 			}
 		}
 
-		if(value instanceof JSON) {
+		return jsonToBean(targetType, value, ignoreError);
+	}
+
+	/**
+	 * JSON递归转换<br>
+	 * 首先尝试JDK类型转换，如果失败尝试JSON转Bean
+	 *
+	 * @param <T> 转换后的对象类型
+	 * @param targetType 目标类型
+	 * @param value 值，JSON格式
+	 * @param ignoreError 是否忽略转换错误
+	 * @return 目标类型的值
+	 * @throws ConvertException 转换失败
+	 */
+	protected static <T> T jsonToBean(Type targetType, Object value, boolean ignoreError) throws ConvertException {
+		if (JSONUtil.isNull(value)) {
+			return null;
+		}
+
+		if(value instanceof JSON){
 			final JSONDeserializer<?> deserializer = GlobalSerializeMapping.getDeserializer(targetType);
 			if(null != deserializer) {
-				return (T) deserializer.deserialize((JSON)value);
+				//noinspection unchecked
+				return (T) deserializer.deserialize((JSON) value);
 			}
 		}
 
@@ -111,5 +131,4 @@ public class JSONConverter implements Converter<JSON> {
 	public JSON convert(Object value, JSON defaultValue) throws IllegalArgumentException {
 		return JSONUtil.parse(value);
 	}
-
 }

hutool-json/src/main/java/cn/hutool/json/JSONSupport.java

@@ -26,7 +26,7 @@ public class JSONSupport implements JSONString, JSONBeanParser<JSON> {
 	 */
 	@Override
 	public void parse(JSON json) {
-		final JSONSupport support = json.toBean(this.getClass());
+		final JSONSupport support = JSONConverter.jsonToBean(getClass(), json, false);
 		BeanUtil.copyProperties(support, this);
 	}
 

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

@@ -0,0 +1,37 @@
+package cn.hutool.json;
+
+import cn.hutool.core.lang.Console;
+import lombok.Data;
+import lombok.EqualsAndHashCode;
+import org.junit.Test;
+
+public class JSONSupportTest {
+
+	@Test
+	public void parseTest() {
+		String jsonstr = "{\n" +
+				"    \"location\": \"http://www.bejson.com\",\n" +
+				"    \"message\": \"这是一条测试消息\",\n" +
+				"    \"requestId\": \"123456789\",\n" +
+				"    \"traceId\": \"987654321\"\n" +
+				"}";
+
+
+		final TestBean testBean = JSONUtil.toBean(jsonstr, TestBean.class);
+		Console.log(testBean);
+	}
+
+	@EqualsAndHashCode(callSuper = true)
+	@Data
+	static class TestBean  extends JSONSupport{
+
+		private String location;
+
+		private String message;
+
+		private String requestId;
+
+		private String traceId;
+
+	}
+}