AVRO bare usage

README.md

https://avro.apache.org/docs/1.8.2/gettingstartedjava.html

http://cr.openjdk.java.net/~rfield/tutorial/JShellTutorial.html

https://gist.github.com/carloslima/af2cc498164aba8e4073367409353628

avro_demo_setup.sh

apt-get install maven openjdk-11-jdk-headless

cat > pom.xml << "EOF"
<project
  xmlns="http://maven.apache.org/POM/4.0.0"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
 <modelVersion>4.0.0</modelVersion>
 <artifactId>hoge</artifactId>
 <groupId>demo</groupId>
 <version>0.1</version>
 <dependencies>
  <dependency>
   <groupId>org.apache.avro</groupId>
   <artifactId>avro</artifactId>
   <version>1.8.1</version>
  </dependency>
  <dependency>
   <groupId>org.apache.avro</groupId>
   <artifactId>avro-tools</artifactId>
   <version>1.8.1</version>
  </dependency>
 </dependencies>
</project>
EOF

mvn dependency:copy-dependencies -DoutputDirectory=cp

cat > ping.avsc << "EOF"
{
 "type":"record",
 "namespace": "demo",
 "name":"Ping",
 "fields": []
}
EOF

java -jar cp/avro-tools-1.8.1.jar compile schema ping.avsc .
javac --class-path cp/avro-1.8.1.jar:cp/jackson-core-asl-1.9.13.jar demo/Ping.java

jshell --class-path=.:$(echo cp/*.jar|sed "s/ /:/g") --module-path=.
# exit from jshell by typing "/exit" or CTRL-D

avro_out.jshell

import java.io.*;
import org.apache.avro.io.*;
import org.apache.avro.file.*;
import org.apache.avro.specific.*;
import demo.*;
Ping p=new Ping();
DatumWriter<Ping> dw = new SpecificDatumWriter<Ping>(Ping.class);
DataFileWriter<Ping> dfw = new DataFileWriter<Ping>(dw);
dfw.create(p.getSchema(), new File("demo.avro"));
dfw.append(p);
dfw.close();

json_out.jshell

import org.apache.avro.generic.*;
import org.apache.avro.io.EncoderFactory;
import demo.*;
var schema = Ping.getClassSchema();
var out = new FileOutputStream("demo.json");
var writer = new GenericDatumWriter<GenericRecord>(schema);
var enc = EncoderFactory.get().jsonEncoder(schema, out);
var p = new Ping();
p.setXid("hogehoge");
writer.write(p, enc);
enc.flush();
out.close();