使用GenericRecord在Avro中填充嵌套记录的问题

Question

假设我有以下架构：

{
 "name" : "Profile",
 "type" : "record",
 "fields" : [
  { "name" : "firstName", "type" : "string" },
  { "name" : "address" , "type" : {
   "type" : "record",
   "name" : "AddressUSRecord",
   "fields" : [
    { "name" : "address1" , "type" : "string" },
    { "name" : "address2" , "type" : "string" },
    { "name" : "city" , "type" : "string" },
    { "name" : "state" , "type" : "string" },
    { "name" : "zip" , "type" : "int" },
    { "name" : "zip4", "type": "int" }
   ]
  }
 }
]
}

我正在使用GenericRecord来表示创建的每个配置文件。要添加firstName，可以轻松执行以下操作：

Schema  sch =  Schema.parse(schemaFile);
DataFileWriter<GenericRecord> fw = new DataFileWriter<GenericRecord>(new GenericDatumWriter<GenericRecord>()).create(sch, new File(outFile));
GenericRecord r = new GenericData.Record(sch);
r.put(“firstName”, “John”);
fw.append(r);

但是我怎么设置城市呢？如何将键表示为r.put方法可以理解的字符串？

由于

Answer 1

对于上面的架构：

GenericRecord t = new GenericData.Record(sch.getField("address").schema());
t.put("city","beijing");
r.put("address",t);