为具有泛型类型的Java POJO生成Avro架构

public class GenericPOJO<T> {
    private T data;

    public T getData() {
        return data;
    }

    public void setData(T data) {
        this.data = data;
    }
}

java -jar avro-tools.jar compile schema GenericPOJO.avsc .

import org.apache.avro.Schema;
import org.apache.avro.file.DataFileReader;
import org.apache.avro.file.DataFileWriter;
import org.apache.avro.generic.GenericDatumReader;
import org.apache.avro.generic.GenericDatumWriter;
import org.apache.avro.generic.GenericRecord;
import org.apache.avro.io.DatumReader;
import org.apache.avro.io.DatumWriter;
import org.apache.avro.io.Encoder;
import org.apache.avro.io.EncoderFactory;
import org.apache.avro.io.Decoder;
import org.apache.avro.io.DecoderFactory;

public class AvroSerializationExample {
    public static void main(String[] args) throws Exception {
        // 创建Avro架构的Schema对象
        Schema schema = new Schema.Parser().parse(AvroSerializationExample.class.getResourceAsStream("GenericPOJO.avsc"));

        // 创建GenericRecord对象，用于存储数据
        GenericRecord record = new GenericData.Record(schema);
        record.put("data", "Hello Avro!");

        // 将数据序列化为Avro二进制格式
        DatumWriter<GenericRecord> writer = new GenericDatumWriter<>(schema);
        DataFileWriter<GenericRecord> fileWriter = new DataFileWriter<>(writer);
        fileWriter.create(schema, new File("data.avro"));
        fileWriter.append(record);
        fileWriter.close();

        // 从Avro二进制格式反序列化数据
        DatumReader<GenericRecord> reader = new GenericDatumReader<>(schema);
        DataFileReader<GenericRecord> fileReader = new DataFileReader<>(new File("data.avro"), reader);
        GenericRecord result = fileReader.next();
        String data = (String) result.get("data");
        fileReader.close();

        System.out.println(data); // 输出：Hello Avro!
    }
}