diff --git a/src/main/java/org/redkale/convert/json/JsonArray.java b/src/main/java/org/redkale/convert/json/JsonArray.java
index 8dcde5fd4..4ed2ae123 100644
--- a/src/main/java/org/redkale/convert/json/JsonArray.java
+++ b/src/main/java/org/redkale/convert/json/JsonArray.java
@@ -38,7 +38,7 @@ public class JsonArray extends ArrayList<Object> implements JsonEntity {
         return convertFrom(text, 0, text.length);
     }
 
-    public static JsonArray convertFrom(char[] text, final int offset, final int length) {
+    public static JsonArray convertFrom(char[] text, int offset, int length) {
         return (JsonArray) JsonEntityDecoder.instance.convertFrom(new JsonReader(text, offset, length));
     }
 
diff --git a/src/main/java/org/redkale/convert/json/JsonObject.java b/src/main/java/org/redkale/convert/json/JsonObject.java
index ed951a7d5..2d10a18e3 100644
--- a/src/main/java/org/redkale/convert/json/JsonObject.java
+++ b/src/main/java/org/redkale/convert/json/JsonObject.java
@@ -34,12 +34,21 @@ public class JsonObject extends LinkedHashMap<String, Object> implements JsonEnt
         return convertFrom(text, 0, text.length);
     }
 
-    public static JsonObject convertFrom(char[] text, final int offset, final int length) {
+    public static JsonObject convertFrom(char[] text, int offset, int length) {
         return (JsonObject) JsonEntityDecoder.instance.convertFrom(new JsonReader(text, offset, length));
     }
 
-    public static JsonObject of(Object javaBean) {
-        return convertFrom(JsonConvert.root().convertTo(javaBean));
+    public static JsonObject of(Object bean) {
+        if (bean instanceof CharSequence) {
+            return convertFrom(bean.toString());
+        }
+        if (bean instanceof JsonObject) {
+            return (JsonObject) bean;
+        }
+        if (bean instanceof Map) {
+            return new JsonObject((Map) bean);
+        }
+        return convertFrom(JsonConvert.root().convertTo(bean));
     }
 
     public JsonObject append(String key, Object value) {
@@ -47,6 +56,11 @@ public class JsonObject extends LinkedHashMap<String, Object> implements JsonEnt
         return this;
     }
 
+    public JsonObject append(String key, Collection value) {
+        super.put(key, value == null || value instanceof JsonArray ? value : new JsonArray(value));
+        return this;
+    }
+
     public JsonObject putObject(String key) {
         JsonObject val = new JsonObject();
         super.put(key, val);
diff --git a/src/main/java/org/redkale/convert/json/JsonString.java b/src/main/java/org/redkale/convert/json/JsonString.java
index 75e171ada..6dfe51fda 100644
--- a/src/main/java/org/redkale/convert/json/JsonString.java
+++ b/src/main/java/org/redkale/convert/json/JsonString.java
@@ -55,7 +55,7 @@ public class JsonString implements CharSequence, JsonEntity, Comparable<JsonStri
 
     @Override
     public int compareTo(JsonString o) {
-        return o == null ? -1 : CharSequence.compare(this, o.getValue());
+        return o == null || o.value == null ? (value == null ? 0 : 1) : (this.value == null ? -1 : this.value.compareTo(o.value));
     }
 
     @Override