add Optional support

hutool-json/src/main/java/org/dromara/hutool/json/InternalJSONUtil.java

@@ -181,7 +181,7 @@ public final class InternalJSONUtil {
 	 * @param string 字符串
 	 * @return 适合在JSON中显示的字符串
 	 */
-	public static String quote(final String string) {
+	public static String quote(final CharSequence string) {
 		return quote(string, true);
 	}
 
@@ -195,7 +195,7 @@ public final class InternalJSONUtil {
 	 * @return 适合在JSON中显示的字符串
 	 * @since 3.3.1
 	 */
-	public static String quote(final String string, final boolean isWrap) {
+	public static String quote(final CharSequence string, final boolean isWrap) {
 		return quote(string, new StringWriter(), isWrap).toString();
 	}
 
@@ -208,7 +208,7 @@ public final class InternalJSONUtil {
 	 * @param writer Writer
 	 * @throws IORuntimeException IO异常
 	 */
-	public static void quote(final String str, final Writer writer) throws IORuntimeException {
+	public static void quote(final CharSequence str, final Writer writer) throws IORuntimeException {
 		quote(str, writer, true);
 	}
 
@@ -224,7 +224,7 @@ public final class InternalJSONUtil {
 	 * @throws IORuntimeException IO异常
 	 * @since 3.3.1
 	 */
-	public static Writer quote(final String str, final Writer writer, final boolean isWrap) throws IORuntimeException {
+	public static Writer quote(final CharSequence str, final Writer writer, final boolean isWrap) throws IORuntimeException {
 		try {
 			return _quote(str, writer, isWrap);
 		} catch (final IOException e) {
@@ -332,7 +332,7 @@ public final class InternalJSONUtil {
 	 * @throws IOException IO异常
 	 * @since 3.3.1
 	 */
-	private static Writer _quote(final String str, final Writer writer, final boolean isWrap) throws IOException {
+	private static Writer _quote(final CharSequence str, final Writer writer, final boolean isWrap) throws IOException {
 		if (StrUtil.isEmpty(str)) {
 			if (isWrap) {
 				writer.write("\"\"");

hutool-json/src/main/java/org/dromara/hutool/json/convert/JSONConverter.java

@@ -21,6 +21,7 @@ import org.dromara.hutool.core.convert.ConvertException;
 import org.dromara.hutool.core.convert.Converter;
 import org.dromara.hutool.core.convert.RegisterConverter;
 import org.dromara.hutool.core.convert.impl.*;
+import org.dromara.hutool.core.lang.Opt;
 import org.dromara.hutool.core.map.MapWrapper;
 import org.dromara.hutool.core.reflect.ConstructorUtil;
 import org.dromara.hutool.core.reflect.TypeReference;
@@ -35,10 +36,7 @@ import org.dromara.hutool.json.serialize.JSONStringer;
 import java.io.Serializable;
 import java.lang.reflect.Type;
 import java.time.temporal.TemporalAccessor;
-import java.util.Collection;
+import java.util.*;
-import java.util.Date;
-import java.util.Iterator;
-import java.util.Map;
 
 /**
  * JSON转换器，实现Object对象转换为{@link JSON}，支持的对象：
@@ -136,10 +134,17 @@ public class JSONConverter implements Converter, Serializable {
 	 * @throws JSONException 转换异常
 	 */
 	@SuppressWarnings("resource")
-	public Object toJSON(final Object obj) throws JSONException {
+	public Object toJSON(Object obj) throws JSONException {
 		if(null == obj){
 			return null;
 		}
+
+		if(obj instanceof Optional){
+			obj = ((Optional<?>) obj).orElse(null);
+		} else if(obj instanceof Opt){
+			obj = ((Opt<?>) obj).get();
+		}
+
 		final JSON json;
 		if (obj instanceof JSON || obj instanceof Number || obj instanceof Boolean) {
 			return obj;
@@ -159,8 +164,8 @@ public class JSONConverter implements Converter, Serializable {
 					// RFC8259，JSON字符串值、number, boolean, or null
 					final Object value = new JSONTokener(jsonStr, config).nextValue(false);
 					if(ObjUtil.equals(value, jsonStr)){
-						// 原值返回，意味着非正常数字、Boolean或null
+						// 非可解析的字符串，原样返回
-						throw new JSONException("Unsupported JSON String: {}", jsonStr);
+						return InternalJSONUtil.quote((CharSequence) value);
 					}
 					return value;
 			}

hutool-json/src/test/java/org/dromara/hutool/json/Issue3681Test.java

@@ -0,0 +1,46 @@
+/*
+ * Copyright (c) 2024. looly(loolly@aliyun.com)
+ * Hutool is licensed under Mulan PSL v2.
+ * You can use this software according to the terms and conditions of the Mulan PSL v2.
+ * You may obtain a copy of Mulan PSL v2 at:
+ *          https://license.coscl.org.cn/MulanPSL2
+ * THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
+ * EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
+ * MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
+ * See the Mulan PSL v2 for more details.
+ */
+
+package org.dromara.hutool.json;
+
+import org.dromara.hutool.core.lang.Opt;
+import org.dromara.hutool.core.map.MapUtil;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+import java.util.Optional;
+
+public class Issue3681Test {
+	@Test
+	void toJsonStrOfOptionalTest() {
+		String abc = JSONUtil.toJsonStr(Optional.of("abc"));
+		Assertions.assertEquals("\"abc\"", abc);
+
+		abc = JSONUtil.toJsonStr(Optional.of("123"));
+		Assertions.assertEquals("123", abc);
+	}
+
+	@Test
+	void toJsonStrOfOptionalTest2() {
+		final String abc = JSONUtil.toJsonStr(Optional.of(MapUtil.of("a", 1)));
+		Assertions.assertEquals("{\"a\":1}", abc);
+	}
+
+	@Test
+	void toJsonStrOfOptTest() {
+		String abc = JSONUtil.toJsonStr(Opt.of("abc"));
+		Assertions.assertEquals("\"abc\"", abc);
+
+		abc = JSONUtil.toJsonStr(Opt.of("123"));
+		Assertions.assertEquals("123", abc);
+	}
+}

hutool-json/src/test/java/org/dromara/hutool/json/IssueI6LBZATest.java

@@ -32,11 +32,10 @@ public class IssueI6LBZATest {
 
 	@Test
 	public void parseJSONErrorTest() {
-		Assertions.assertThrows(JSONException.class, ()->{
 		final String a = "a";
 		final Object parse = JSONUtil.parse(a);
 		Assertions.assertEquals(String.class, parse.getClass());
-		});
+		Assertions.assertEquals("\"a\"", parse);
 	}
 
 	@Test

hutool-json/src/test/java/org/dromara/hutool/json/JSONUtilTest.java

@@ -31,13 +31,6 @@ public class JSONUtilTest {
 
 	@Test
 	public void parseInvalid() {
-		Assertions.assertThrows(JSONException.class, ()->{
-			JSONUtil.parse("abc");
-		});
-	}
-
-	@Test
-	public void parseInvalid2() {
 		Assertions.assertThrows(JSONException.class, ()->{
 			JSONUtil.parse("'abc");
 		});
@@ -312,13 +305,10 @@ public class JSONUtilTest {
 
 	@Test
 	public void toJsonStrOfStringTest(){
-		Assertions.assertThrows(JSONException.class, ()->{
 		final String a = "a";
 
-			// 普通字符串不能解析为JSON字符串，必须由双引号或者单引号包裹
 		final String s = JSONUtil.toJsonStr(a);
-			Assertions.assertEquals(a, s);
+		Assertions.assertEquals("\"a\"", s);
-		});
 	}
 
 	@Test