Qiangqiang Shi created AVRO-1763:
------------------------------------
Summary: Avro Schema Generator to handle polymorphic types
Key: AVRO-1763
URL: https://issues.apache.org/jira/browse/AVRO-1763
Project: Avro
Issue Type: Improvement
Affects Versions: 1.9.0
Reporter: Qiangqiang Shi
Inheritance and polymorphism are widely used in Java libraries. If multiple
sophisticated Avro schema generator can be added to Avro, users can generate
Avro schema easily for classes in complex context, third-party code and legacy
code.
For example, for the following class:
{code:java}
public class TestReflectPolymorphismData {
{
public static class SuperclassA1 {
private String SuperclassA1;
}
public static class SubclassA1 extends SuperclassA1 {
private String SubclassA1;
}
public static class SubclassA2 extends SuperclassA1 {
private String SubclassA2;
}
public static class SuperB1 {
private SubclassA1 SubclassA1;
private List<SubclassA2> SubclassA2List;
private Map<String, SuperclassA1> stringSuperclassA1Map;
private Map<Integer, SuperclassA1> integerSuperclassA1Map;
}
}
}
{code}
It'll be good if Avro can provide a schema generator to generate a schema like
the following automatically for class SuperB1 :
{code:json}
{
"type":"record",
"name":"SuperB1",
"namespace":"org.apache.avro.reflect.TestReflectPolymorphismData$","fields":[{"name":"SubclassA1","type":{"type":"record","name":"SuperclassA1","fields":[{"name":"SuperclassA1","type":"string"},{"name":"SuperclassA1Subclasses","type":["null",{"type":"record","name":"SubclassA1","fields":[{"name":"SubclassA1","type":"string"}]},{"type":"record","name":"SubclassA2","fields":[{"name":"SubclassA2","type":"string"}]}]}]}},{"name":"SubclassA2List","type":{"type":"array","items":"SuperclassA1","java-class":"java.util.List"}},{"name":"stringSuperclassA1Map","type":{"type":"map","values":"SuperclassA1"}},{"name":"integerSuperclassA1Map","type":{"type":"array","items":{"type":"record","name":"Pair34255fab6d3d79ff","namespace":"org.apache.avro.reflect","fields":[{"name":"key","type":"int"},{"name":"value","type":"org.apache.avro.reflect.TestReflectPolymorphismData$.SuperclassA1"}]},"java-class":"java.util.Map"}}]}
{code}
related story: AVRO-1568
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
