add new interface

src/main/java/com/huobi/wss/event/SwapContractElementSubResponse.java

@@ -0,0 +1,49 @@
+package com.huobi.wss.event;
+import com.google.gson.annotations.SerializedName;
+import lombok.AllArgsConstructor;
+import lombok.Data;
+
+import java.math.BigDecimal;
+import java.util.List;
+
+@Data
+@AllArgsConstructor
+public class SwapContractElementSubResponse {
+    public String op;
+    public String topic;
+    public long ts;
+    public Data data;
+
+    public static class Data {
+        public String contract_code;
+        public String instrument_index_code;
+        public Integer real_time_settlement;
+        public BigDecimal transfer_profit_ratio;
+        public Integer min_level;
+        public Integer max_level;
+        public List<ContractInfo> contract_infos;
+        public Integer open_order_limit;
+        public Integer offset_order_limit;
+        public Integer long_position_limit;
+        public Integer short_position_limit;
+        public String price_tick;
+        public String instrument_value;
+        public Integer settle_period;
+        public Integer funding_rate_cap;
+        public Integer funding_rate_floor;
+        public Integer hig_normal_limit;
+        public Integer min_normal_limit;
+        public Integer hig_open_limit;
+        public Integer min_open_limit;
+        public Integer hig_trade_limit;
+        public Integer min_trade_limit;
+    }
+
+    public static class ContractInfo {
+        public String contract_code;
+        public String delivery_time;
+        public String create_date;
+        public Integer contract_status;
+        public String settlement_date;
+    }
+}