From 6002a1476f78732bedd7f7f312fedb390b235ebc Mon Sep 17 00:00:00 2001
From: Looly <loolly@gmail.com>
Date: Wed, 29 Sep 2021 10:12:58 +0800
Subject: [PATCH] fix add bug

---
 CHANGELOG.md                                             | 1 +
 hutool-json/src/main/java/cn/hutool/json/JSONArray.java  | 2 +-
 .../src/test/java/cn/hutool/json/JSONArrayTest.java      | 9 +++++++++
 3 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index f08a76265..7ac1de802 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -21,6 +21,7 @@
 * 【json   】     修复JSONGetter.getJSONArray判断null的问题（issue#I4C15H@Gitee）
 * 【db     】     修复Condition没占位符的情况下sql没引号问题（issue#1846@Github）
 * 【cache  】     修复FIFOCache中remove回调无效问题（pr#1856@Github）
+* 【json   】     修复JSONArray.set中，index为0报错问题（issue#1858@Github）
 
 -------------------------------------------------------------------------------------------------------------
 
diff --git a/hutool-json/src/main/java/cn/hutool/json/JSONArray.java b/hutool-json/src/main/java/cn/hutool/json/JSONArray.java
index 3b45390f3..fdfafabc7 100644
--- a/hutool-json/src/main/java/cn/hutool/json/JSONArray.java
+++ b/hutool-json/src/main/java/cn/hutool/json/JSONArray.java
@@ -449,7 +449,7 @@ public class JSONArray implements JSON, JSONGetter<Integer>, List<Object>, Rando
 	 */
 	@Override
 	public Object set(int index, Object element) {
-		if(index > size()){
+		if(index >= size()){
 			add(index, element);
 		}
 		return this.rawList.set(index, JSONUtil.wrap(element, this.config));
diff --git a/hutool-json/src/test/java/cn/hutool/json/JSONArrayTest.java b/hutool-json/src/test/java/cn/hutool/json/JSONArrayTest.java
index caf4c18ab..c4f8c6b6a 100644
--- a/hutool-json/src/test/java/cn/hutool/json/JSONArrayTest.java
+++ b/hutool-json/src/test/java/cn/hutool/json/JSONArrayTest.java
@@ -217,6 +217,15 @@ public class JSONArrayTest {
 		Assert.assertEquals(4, jsonArray.size());
 	}
 
+	// https://github.com/dromara/hutool/issues/1858
+	@Test
+	public void putTest2(){
+		final JSONArray jsonArray = new JSONArray();
+		jsonArray.put(0, 1);
+		Assert.assertEquals(1, jsonArray.size());
+		Assert.assertEquals(1, jsonArray.get(0));
+	}
+
 	private static Map<String, String> buildMap(String id, String parentId, String name) {
 		Map<String, String> map = new HashMap<>();
 		map.put("id", id);