diff --git a/mirai-core/src/main/java/net/mamoe/mirai/network/packet/client/ClientPacket.java b/mirai-core/src/main/java/net/mamoe/mirai/network/packet/client/ClientPacket.java
index 700d4990f..8dccc0620 100644
--- a/mirai-core/src/main/java/net/mamoe/mirai/network/packet/client/ClientPacket.java
+++ b/mirai-core/src/main/java/net/mamoe/mirai/network/packet/client/ClientPacket.java
@@ -13,8 +13,8 @@ public abstract class ClientPacket extends DataOutputStream implements Packet {
         super(new ByteArrayOutputStream());
     }
 
-    public long readQQ() {
-
+    protected void writeQQHex(long qq) {
+        this.write
     }
 
     /**
diff --git a/mirai-core/src/test/java/NetworkTest.java b/mirai-core/src/test/java/NetworkTest.java
new file mode 100644
index 000000000..31deeaed2
--- /dev/null
+++ b/mirai-core/src/test/java/NetworkTest.java
@@ -0,0 +1,10 @@
+/**
+ * @author Him188moe @ Mirai Project
+ */
+public class NetworkTest {
+    public static void main(String[] args) {
+
+
+        Long.valueOf("", 16);
+    }
+}