// 3 element map
prot.readFieldBegin();
TMap m = prot.readMapBegin();
assertTrue(m.size == 3);
assertTrue(prot.readString().equals("key1"));
assertTrue(prot.readString().equals("val1"));
assertTrue(prot.readString().equals("key2"));
assertTrue(prot.readString().equals("val2"));
assertTrue(prot.readString().equals("key3"));
assertTrue(prot.readString().equals("val3"));