Dynamically insert Enum symbols with Avro java api

Question

I'm writing a schema for a java class that has an enum field. I'm using the java schema builder like this:

public Schema schema = SchemaBuilder
    .record("MyRecord").namespace("my.name.space")
    .name("myEnum").type().enumeration("MyEnumClass").namespace("enum.name.space")
        .symbols("S1", ..., "S1000").noDefault()
    .endRecord()

The problem is that there are hundreds of Enum values in MyEnumClass. The class is accessible from my code. How can I insert them dynamically into .symbles() without manually typing them?

Answer 1

You can create avro schema for your class automatically.

For example.

Enum:

public enum TestEnum {
    VAL1,
    VAL2,
    VAL3
}

Class with enum field:

public class TestClass {
    public TestEnum testEnum;

    public TestClass() {

    }

    public TestClass(TestEnum testEnum) {
        this.testEnum = testEnum;
    }

    public TestEnum getTestEnum() {
        return testEnum;
    }

    public void setTestEnum(TestEnum testEnum) {
        this.testEnum = testEnum;
    }
}

Generating schema:

Schema schema = ReflectData.get().getSchema(TestClass.class);

Result:

{
  "type": "record",
  "name": "TestClass",
  "namespace": "q42698247",
  "fields": [
    {
      "name": "testEnum",
      "type": {
        "type": "enum",
        "name": "TestEnum",
        "symbols": [
          "VAL1",
          "VAL2",
          "VAL3"
        ]
      }
    }
  ]
}