add packet test: LpPacketTest

src/main/java/packet/Data.java

@@ -33,13 +33,25 @@ import encoding.*;
 //             }
 //
 public class Data implements IEncodingAble, InteractWithField {
-    public MINPacket minPacket=new MINPacket();
+    private MINPacket minPacket=new MINPacket();
     public FreshnessPeriod freshnessPeriod=new FreshnessPeriod();
     public Payload payload=new Payload();
     public CongestionMark congestionMark=new CongestionMark();
     public NackHeader nackHeader=new NackHeader();
     public Identifier name=new Identifier();
 
+    public Data(){
+    }
+
+    public Data(Identifier name,Payload payload,FreshnessPeriod freshnessPeriod,
+                CongestionMark congestionMark,NackHeader nackHeader){
+        this.name=name;
+        this.payload=payload;
+        this.freshnessPeriod=freshnessPeriod;
+        this.congestionMark=congestionMark;
+        this.nackHeader=nackHeader;
+    }
+
     /**
      * 展示数据包的 URI
      *