prot.writeString("key2");
prot.writeString("val2");
prot.writeString("key3");
prot.writeString("val3");
prot.writeMapEnd();
prot.writeFieldEnd();
prot.writeFieldBegin(new TField());
prot.writeListBegin(new TList());
prot.writeString("elem1");
prot.writeString("elem2");