Merger Result Extension

Extension Description

Merging return results, used for grouping aggregation.

Extension Interface

org.apache.dubbo.rpc.cluster.Merger

Extension 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

Extension Example

Maven project structure:

src
 |-main
    |-java
        |-com
            |-xxx
                |-XxxMerger.java (implements 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