Merge result extension

Expansion Description

Merge returns results for grouping and aggregation.

Extension ports

org.apache.dubbo.rpc.cluster.Merger

Extended configuration

<dubbo:method merger="xxx" />

Known extensions

  • org.apache.dubbo.rpc.cluster.merger.ArrayMerger
  • org.apache.dubbo.rpc.cluster.merger.ListMerger
  • org.apache.dubbo.rpc.cluster.merger.SetMerger
  • org.apache.dubbo.rpc.cluster.merger.MapMerger
  • org.apache.dubbo.rpc.cluster.merger.ByteArrayMerger
  • org.apache.dubbo.rpc.cluster.merger.CharArrayMerger
  • org.apache.dubbo.rpc.cluster.merger.ShortArrayMerger
  • org.apache.dubbo.rpc.cluster.merger.IntArrayMerger
  • org.apache.dubbo.rpc.cluster.merger.LongArrayMerger
  • org.apache.dubbo.rpc.cluster.merger.FloatArrayMerger
  • org.apache.dubbo.rpc.cluster.merger.DoubleArrayMerger
  • org.apache.dubbo.rpc.cluster.merger.BooleanArrayMerger

Extended example

Maven project structure:

src
 |-main
    |-java
        |-com
            |-xxx
                |-XxxMerger.java (implement Merger interface)
    |-resources
        |-META-INF
            |-dubbo
                |-org.apache.dubbo.rpc.cluster.Merger (plain text file, content: xxx=com.xxx.XxxMerger)

XxxMerger.java:

package com.xxx;
 
import org.apache.dubbo.rpc.cluster.Merger;
 
public class XxxMerger<T> implements Merger<T> {
    public T merge(T... results) {
        //...
    }
}

META-INF/dubbo/org.apache.dubbo.rpc.cluster.Merger:

xxx=com.xxx.XxxMerger

Last modified January 2, 2023: Enhance en docs (#1798) (95a9f4f6c1)