[AVRO-1214] Generated protocol's method should return void instead of Void like one-way message

• Type: Improvement
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 1.7.2
• Fix Version/s: 1.9.0
• Component/s: java
• Hadoop Flags: Incompatible change
• Assignee: Daniel Kulp
• Reporter: Sébastien Launay
• Created: 05/Dec/12 19:54
• Updated: 17/Jan/19 20:42
• Resolved: 17/Jan/19 20:28

Description

Using the following IDL:

@namespace("org.apache.avro.test")
protocol Simple {
  error TestError {
    string message;
  }

  string hello(string greeting);
  void `error`() throws TestError;
  void ping() oneway;
}

Will produce the interface:

package org.apache.avro.test;

public interface Simple {
  public static final org.apache.avro.Protocol PROTOCOL = org.apache.avro.Protocol.parse("...");
  java.lang.CharSequence hello(java.lang.CharSequence greeting) throws org.apache.avro.AvroRemoteException;
  java.lang.Void error() throws org.apache.avro.AvroRemoteException, org.apache.avro.test.TestError;
  void ping();

  public interface Callback extends Simple {
    public static final org.apache.avro.Protocol PROTOCOL = org.apache.avro.test.Simple.PROTOCOL;
    void hello(java.lang.CharSequence greeting, org.apache.avro.ipc.Callback<java.lang.CharSequence> callback) throws java.io.IOException;
    void error(org.apache.avro.ipc.Callback<java.lang.Void> callback) throws java.io.IOException;
  }
}

Then one is forced to add return null; statement(s) in the interface implementation for the error() method which can be a bit cumbersome and that's not the case for the oneway ping() method.
This is fine on the Callback though because the developer can just ignore the callback argument.