我认为不可能直接使用 ConfluentRegistryAvroDeserializationSchema.forGeneric . 它打算与读卡器模式一起使用，并且它们具有检查这一点的前提条件。
你必须实现你自己的。两件重要的事情：
套 specific.avro.reader 为false（否则会得到特定的记录）
这个 KafkaAvroDeserializer 必须延迟初始化（因为它本身不可序列化，因为它持有对schema registry客户机的引用）

import io.confluent.kafka.schemaregistry.client.CachedSchemaRegistryClient;
import io.confluent.kafka.schemaregistry.client.SchemaRegistryClient;
import io.confluent.kafka.serializers.AbstractKafkaAvroSerDeConfig;
import io.confluent.kafka.serializers.KafkaAvroDeserializer;
import io.confluent.kafka.serializers.KafkaAvroDeserializerConfig;
import java.util.HashMap;
import java.util.Map;
import org.apache.avro.generic.GenericRecord;
import org.apache.flink.api.common.typeinfo.TypeInformation;
import org.apache.flink.api.java.typeutils.TypeExtractor;
import org.apache.flink.streaming.util.serialization.KeyedDeserializationSchema;
public class KafkaGenericAvroDeserializationSchema
    implements KeyedDeserializationSchema<GenericRecord> {
  private final String registryUrl;
  private transient KafkaAvroDeserializer inner;
  public KafkaGenericAvroDeserializationSchema(String registryUrl) {
    this.registryUrl = registryUrl;
  }
  @Override
  public GenericRecord deserialize(
      byte[] messageKey, byte[] message, String topic, int partition, long offset) {
    checkInitialized();
    return (GenericRecord) inner.deserialize(topic, message);
  }
  @Override
  public boolean isEndOfStream(GenericRecord nextElement) {
    return false;
  }
  @Override
  public TypeInformation<GenericRecord> getProducedType() {
    return TypeExtractor.getForClass(GenericRecord.class);
  }
  private void checkInitialized() {
    if (inner == null) {
      Map<String, Object> props = new HashMap<>();
      props.put(AbstractKafkaAvroSerDeConfig.SCHEMA_REGISTRY_URL_CONFIG, registryUrl);
      props.put(KafkaAvroDeserializerConfig.SPECIFIC_AVRO_READER_CONFIG, false);
      SchemaRegistryClient client =
          new CachedSchemaRegistryClient(
              registryUrl, AbstractKafkaAvroSerDeConfig.MAX_SCHEMAS_PER_SUBJECT_DEFAULT);
      inner = new KafkaAvroDeserializer(client, props);
    }
  }
}

env.addSource(
  new FlinkKafkaConsumer<>(
    topic, 
    new KafkaGenericAvroDeserializationSchema(schemaReigstryUrl), 
    kafkaProperties));