More update to support Reducer Builders

src/main/java/org/elasticsearch/search/aggregations/AggregationBuilder.java

@@ -20,12 +20,14 @@
 package org.elasticsearch.search.aggregations;
 
 import com.google.common.collect.Lists;
+
 import org.elasticsearch.ElasticsearchGenerationException;
 import org.elasticsearch.client.Requests;
 import org.elasticsearch.common.bytes.BytesArray;
 import org.elasticsearch.common.bytes.BytesReference;
 import org.elasticsearch.common.xcontent.XContentBuilder;
 import org.elasticsearch.common.xcontent.XContentFactory;
+import org.elasticsearch.search.aggregations.reducers.ReducerBuilder;
 
 import java.io.IOException;
 import java.util.List;
@@ -37,6 +39,7 @@ import java.util.Map;
 public abstract class AggregationBuilder<B extends AggregationBuilder<B>> extends AbstractAggregationBuilder {
 
     private List<AbstractAggregationBuilder> aggregations;
+    private List<ReducerBuilder<?>> reducers;
     private BytesReference aggregationsBinary;
     private Map<String, Object> metaData;
 
@@ -59,6 +62,18 @@ public abstract class AggregationBuilder<B extends AggregationBuilder<B>> extend
         return (B) this;
     }
 
+    /**
+     * Add a sub get to this bucket get.
+     */
+    @SuppressWarnings("unchecked")
+    public B subAggregation(ReducerBuilder<?> reducer) {
+        if (reducers == null) {
+            reducers = Lists.newArrayList();
+        }
+        reducers.add(reducer);
+        return (B) this;
+    }
+
     /**
      * Sets a raw (xcontent / json) sub addAggregation.
      */
@@ -120,7 +135,7 @@ public abstract class AggregationBuilder<B extends AggregationBuilder<B>> extend
         builder.field(type);
         internalXContent(builder, params);
 
-        if (aggregations != null || aggregationsBinary != null) {
+        if (aggregations != null || aggregationsBinary != null || reducers != null) {
             builder.startObject("aggregations");
 
             if (aggregations != null) {
@@ -129,6 +144,12 @@ public abstract class AggregationBuilder<B extends AggregationBuilder<B>> extend
                 }
             }
 
+            if (reducers != null) {
+                for (ReducerBuilder<?> subAgg : reducers) {
+                    subAgg.toXContent(builder, params);
+                }
+            }
+
             if (aggregationsBinary != null) {
                 if (XContentFactory.xContentType(aggregationsBinary) == builder.contentType()) {
                     builder.rawField("aggregations", aggregationsBinary);

src/main/java/org/elasticsearch/search/aggregations/TransportAggregationModule.java

@@ -57,6 +57,7 @@ import org.elasticsearch.search.aggregations.metrics.stats.extended.InternalExte
 import org.elasticsearch.search.aggregations.metrics.sum.InternalSum;
 import org.elasticsearch.search.aggregations.metrics.tophits.InternalTopHits;
 import org.elasticsearch.search.aggregations.metrics.valuecount.InternalValueCount;
+import org.elasticsearch.search.aggregations.reducers.InternalSimpleValue;
 import org.elasticsearch.search.aggregations.reducers.derivative.DerivativeReducer;
 
 /**
@@ -103,6 +104,7 @@ public class TransportAggregationModule extends AbstractModule implements SpawnM
         InternalTopHits.registerStreams();
         InternalGeoBounds.registerStream();
         InternalChildren.registerStream();
+        InternalSimpleValue.registerStreams();
 
         // Reducers
         DerivativeReducer.registerStreams();

src/main/java/org/elasticsearch/search/aggregations/bucket/histogram/InternalHistogram.java

@@ -301,6 +301,10 @@ public class InternalHistogram<B extends InternalHistogram.Bucket> extends Inter
         return factory;
     }
 
+    public InternalOrder getOrder() {
+        return order;
+    }
+
     private static class IteratorAndCurrent<B> {
 
         private final Iterator<B> iterator;

src/main/java/org/elasticsearch/search/aggregations/bucket/histogram/InternalOrder.java

@@ -29,7 +29,7 @@ import java.util.Comparator;
 /**
  * An internal {@link Histogram.Order} strategy which is identified by a unique id.
  */
-class InternalOrder extends Histogram.Order {
+public class InternalOrder extends Histogram.Order {
 
     final byte id;
     final String key;

src/main/java/org/elasticsearch/search/aggregations/reducers/ReducerBuilder.java

@@ -23,7 +23,6 @@ import org.elasticsearch.common.xcontent.ToXContent;
 import org.elasticsearch.common.xcontent.XContentBuilder;
 
 import java.io.IOException;
-import java.util.List;
 import java.util.Map;
 
 /**
@@ -33,7 +32,7 @@ public abstract class ReducerBuilder<B extends ReducerBuilder<B>> implements ToX
 
     private final String name;
     protected final String type;
-    private List<String> bucketsPaths;
+    private String[] bucketsPaths;
     private Map<String, Object> metaData;
 
     /**
@@ -54,7 +53,7 @@ public abstract class ReducerBuilder<B extends ReducerBuilder<B>> implements ToX
     /**
      * Sets the paths to the buckets to use for this reducer
      */
-    public B setBucketsPaths(List<String> bucketsPaths) {
+    public B setBucketsPaths(String... bucketsPaths) {
         this.bucketsPaths = bucketsPaths;
         return (B) this;
     }