diff --git a/src/json_parser.c b/src/json_parser.c
index 924da93..f5369eb 100644
--- a/src/json_parser.c
+++ b/src/json_parser.c
@@ -308,8 +308,9 @@ static inline void json_quote_string(fc_json_context_t
     *buff = p;
 }
 
-const BufferInfo *fc_encode_json_array(fc_json_context_t *context,
-        const string_t *elements, const int count)
+int fc_encode_json_array_ex(fc_json_context_t *context,
+        const string_t *elements, const int count,
+        BufferInfo *buffer)
 {
     const string_t *el;
     const string_t *end;
@@ -322,17 +323,17 @@ const BufferInfo *fc_encode_json_array(fc_json_context_t *context,
         expect_size += 6 * el->len + 3;
     }
 
-    if (context->output.alloc_size < expect_size) {
-        if ((context->error_no=fc_realloc_buffer(&context->output,
-                        context->init_buff_size, expect_size)) != 0)
+    if (buffer->alloc_size < expect_size) {
+        if ((context->error_no=fc_realloc_buffer(buffer, context->
+                        init_buff_size, expect_size)) != 0)
         {
             context->error_info.len = snprintf(context->error_info.str,
                     context->error_size, "realloc buffer fail");
-            return NULL;
+            return context->error_no;
         }
     }
 
-    p = context->output.buff;
+    p = buffer->buff;
     *p++ = '[';
     for (el=elements; el<end; el++) {
         if (el > elements) {
@@ -344,12 +345,13 @@ const BufferInfo *fc_encode_json_array(fc_json_context_t *context,
 
     *p++ = ']';
     *p = '\0';
-    context->output.length = p - context->output.buff;
-    return &context->output;
+    buffer->length = p - buffer->buff;
+    return 0;
 }
 
-const BufferInfo *fc_encode_json_map(fc_json_context_t *context,
-        const key_value_pair_t *elements, const int count)
+int fc_encode_json_map_ex(fc_json_context_t *context,
+        const key_value_pair_t *elements, const int count,
+        BufferInfo *buffer)
 {
     const key_value_pair_t *pair;
     const key_value_pair_t *end;
@@ -362,17 +364,17 @@ const BufferInfo *fc_encode_json_map(fc_json_context_t *context,
         expect_size += 6 * (pair->key.len + pair->value.len) + 5;
     }
 
-    if (context->output.alloc_size < expect_size) {
-        if ((context->error_no=fc_realloc_buffer(&context->output,
-                        context->init_buff_size, expect_size)) != 0)
+    if (buffer->alloc_size < expect_size) {
+        if ((context->error_no=fc_realloc_buffer(buffer, context->
+                        init_buff_size, expect_size)) != 0)
         {
             context->error_info.len = snprintf(context->error_info.str,
                     context->error_size, "realloc buffer fail");
-            return NULL;
+            return context->error_no;
         }
     }
 
-    p = context->output.buff;
+    p = buffer->buff;
     *p++ = '{';
     for (pair=elements; pair<end; pair++) {
         if (pair > elements) {
@@ -386,8 +388,8 @@ const BufferInfo *fc_encode_json_map(fc_json_context_t *context,
 
     *p++ = '}';
     *p = '\0';
-    context->output.length = p - context->output.buff;
-    return &context->output;
+    buffer->length = p - buffer->buff;
+    return 0;
 }
 
 const fc_json_array_t *fc_decode_json_array(fc_json_context_t
diff --git a/src/json_parser.h b/src/json_parser.h
index a25d076..9290bd6 100644
--- a/src/json_parser.h
+++ b/src/json_parser.h
@@ -163,11 +163,37 @@ extern "C" {
 
     int fc_detect_json_type(const string_t *input);
 
-    const BufferInfo *fc_encode_json_array(fc_json_context_t *context,
-            const string_t *elements, const int count);
+    int fc_encode_json_array_ex(fc_json_context_t *context,
+            const string_t *elements, const int count,
+            BufferInfo *buffer);
 
-    const BufferInfo *fc_encode_json_map(fc_json_context_t *context,
-            const key_value_pair_t *elements, const int count);
+    int fc_encode_json_map_ex(fc_json_context_t *context,
+            const key_value_pair_t *elements, const int count,
+            BufferInfo *buffer);
+
+    static inline const BufferInfo *fc_encode_json_array(fc_json_context_t
+            *context, const string_t *elements, const int count)
+    {
+        if (fc_encode_json_array_ex(context, elements, count,
+                    &context->output) == 0)
+        {
+            return &context->output;
+        } else {
+            return NULL;
+        }
+    }
+
+    static inline const BufferInfo *fc_encode_json_map(fc_json_context_t
+            *context, const key_value_pair_t *elements, const int count)
+    {
+        if (fc_encode_json_map_ex(context, elements, count,
+                    &context->output) == 0)
+        {
+            return &context->output;
+        } else {
+            return NULL;
+        }
+    }
 
     const fc_json_array_t *fc_decode_json_array(fc_json_context_t
             *context, const string_t *input);
diff --git a/src/tests/test_json_parser.c b/src/tests/test_json_parser.c
index da8da8a..cca7fe1 100644
--- a/src/tests/test_json_parser.c
+++ b/src/tests/test_json_parser.c
@@ -28,11 +28,12 @@
 
 int main(int argc, char *argv[])
 {
-	int result;
+    int result;
     int json_type;
+    fc_json_context_t json_ctx;
     char error_info[256];
     string_t input;
-    string_t output;
+    BufferInfo output;
 
     if (argc < 2) {
         fprintf(stderr, "Usage: %s <json_string | json_array | json_map>\n",
@@ -42,52 +43,52 @@ int main(int argc, char *argv[])
 	
 	log_init();
 
+    if ((result=fc_init_json_context_ex(&json_ctx, 1024,
+                    error_info, sizeof(error_info))) != 0)
+    {
+        return result;
+    }
+    memset(&output, 0, sizeof(output));
+
     input.str = argv[1];
     input.len = strlen(input.str);
-    json_type = detect_json_type(&input);
+    json_type = fc_detect_json_type(&input);
     if (json_type == FC_JSON_TYPE_ARRAY) {
-        json_array_t array;
+        const fc_json_array_t *array;
 
-        if ((result=decode_json_array(&input, &array, error_info,
-                        sizeof(error_info))) != 0)
-        {
+        if ((array=fc_decode_json_array(&json_ctx, &input)) == NULL) {
             fprintf(stderr, "decode json array fail, %s\n", error_info);
-            return result;
+            return fc_json_parser_get_error_no(&json_ctx);
         }
-                
-        if ((result=encode_json_array(&array, &output,
-                            error_info, sizeof(error_info))) != 0)
+
+        if ((result=fc_encode_json_array_ex(&json_ctx, array->elements,
+                        array->count, &output)) != 0)
         {
             fprintf(stderr, "encode json array fail, %s\n", error_info);
             return result;
         }
 
-        printf("%s\n", output.str);
-        free_json_string(&output);
-        free_json_array(&array);
+        printf("%.*s\n", output.length, output.buff);
     } else if (json_type == FC_JSON_TYPE_MAP) {
-        json_map_t map;
+        const fc_json_map_t *map;
 
-        if ((result=decode_json_map(&input, &map, error_info,
-                        sizeof(error_info))) != 0)
-        {
+        if ((map=fc_decode_json_map(&json_ctx, &input)) == NULL) {
             fprintf(stderr, "decode json map fail, %s\n", error_info);
-            return result;
+            return fc_json_parser_get_error_no(&json_ctx);
         }
-                
-        if ((result=encode_json_map(&map, &output,
-                            error_info, sizeof(error_info))) != 0)
+
+        if ((result=fc_encode_json_map_ex(&json_ctx, map->elements,
+                        map->count, &output)) != 0)
         {
             fprintf(stderr, "encode json map fail, %s\n", error_info);
             return result;
         }
 
-        printf("%s\n", output.str);
-        free_json_string(&output);
-        free_json_map(&map);
+        printf("%.*s\n", output.length, output.buff);
     } else {
         fprintf(stderr, "string\n");
     }
-
+ 
+    fc_destroy_json_context(&json_ctx);
 	return 0;
 }