Remove AggregationStreams and friends

* Remove outdated aggregation registration method
* Remove AggregationStreams
* Adds StreamInput#readNamedWriteableList and
StreamOutput#writeNamedWriteableList convenience methods. We strive to
make the reading and writing from the streams terse so they are easier
to scan visually.
* Remove PipelineAggregatorStreams
* Remove stream info from InternalAggreation.Type
* Remove InternalAggregation#type
* Remove Streamable from PipelineAggregator
* Remove Streamable from MultiBucketsAggregation.Bucket

3 files changed, 3 insertions, 113 deletions

diff --git a/core/src/main/java/org/elasticsearch/search/aggregations/pipeline/PipelineAggregator.java b/core/src/main/java/org/elasticsearch/search/aggregations/pipeline/PipelineAggregator.java
index 446b56d07e..f49ca1dd39 100644
--- a/core/src/main/java/org/elasticsearch/search/aggregations/pipeline/PipelineAggregator.java
+++ b/core/src/main/java/org/elasticsearch/search/aggregations/pipeline/PipelineAggregator.java
@@ -24,19 +24,15 @@ import org.elasticsearch.common.ParseField;
 import org.elasticsearch.common.io.stream.NamedWriteable;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
-import org.elasticsearch.common.io.stream.Streamable;
 import org.elasticsearch.index.query.QueryParseContext;
 import org.elasticsearch.search.aggregations.InternalAggregation;
 import org.elasticsearch.search.aggregations.InternalAggregation.ReduceContext;
-import org.elasticsearch.search.aggregations.InternalAggregation.Type;
 import org.elasticsearch.search.aggregations.PipelineAggregationBuilder;
 
 import java.io.IOException;
 import java.util.Map;
 
-public abstract class PipelineAggregator implements Streamable, NamedWriteable {
-    // NORELEASE remove Streamable
-
+public abstract class PipelineAggregator implements NamedWriteable {
     /**
      * Parse the {@link PipelineAggregationBuilder} from a {@link QueryParseContext}.
      */
@@ -66,9 +62,6 @@ public abstract class PipelineAggregator implements Streamable, NamedWriteable {
     private String[] bucketsPaths;
     private Map<String, Object> metaData;
 
-    protected PipelineAggregator() { // for Serialisation
-    }
-
     protected PipelineAggregator(String name, String[] bucketsPaths, Map<String, Object> metaData) {
         this.name = name;
         this.bucketsPaths = bucketsPaths;
@@ -85,26 +78,8 @@ public abstract class PipelineAggregator implements Streamable, NamedWriteable {
     }
 
     @Override
-    public final void readFrom(StreamInput in) throws IOException {
-        try {
-            getWriteableName(); // Throws UnsupportedOperationException if this aggregation should be read using old style Streams
-            assert false : "Used reading constructor instead";
-        } catch (UnsupportedOperationException e) {
-            // OK
-        }
-        name = in.readString();
-        bucketsPaths = in.readStringArray();
-        metaData = in.readMap();
-        doReadFrom(in);
-    }
-
-    protected void doReadFrom(StreamInput in) throws IOException {
-        throw new UnsupportedOperationException("Use reading constructor instead"); // NORELEASE remove when we remove Streamable
-    }
-
-    @Override
     public final void writeTo(StreamOutput out) throws IOException {
-        out.writeString(name);  // NORELEASE remote writing the name - it is automatically handled with writeNamedWriteable
+        out.writeString(name);
         out.writeStringArray(bucketsPaths);
         out.writeMap(metaData);
         doWriteTo(out);
@@ -112,12 +87,6 @@ public abstract class PipelineAggregator implements Streamable, NamedWriteable {
 
     protected abstract void doWriteTo(StreamOutput out) throws IOException;
 
-    @Override
-    public String getWriteableName() {
-        // NORELEASE remove me when all InternalAggregations override it
-        throw new UnsupportedOperationException("Override on every class");
-    }
-
     public String name() {
         return name;
     }
@@ -130,10 +99,5 @@ public abstract class PipelineAggregator implements Streamable, NamedWriteable {
         return metaData;
     }
 
-    public Type type() {
-        // NORELEASE remove this method
-        throw new UnsupportedOperationException(getClass().getName() + " used type but should Use getWriteableName instead");
-    }
-
     public abstract InternalAggregation reduce(InternalAggregation aggregation, ReduceContext reduceContext);
 }
diff --git a/core/src/main/java/org/elasticsearch/search/aggregations/pipeline/PipelineAggregatorStreams.java b/core/src/main/java/org/elasticsearch/search/aggregations/pipeline/PipelineAggregatorStreams.java
deleted file mode 100644
index ad1dc73f6e..0000000000
--- a/core/src/main/java/org/elasticsearch/search/aggregations/pipeline/PipelineAggregatorStreams.java
+++ /dev/null
@@ -1,69 +0,0 @@
-/*
- * Licensed to Elasticsearch under one or more contributor
- * license agreements. See the NOTICE file distributed with
- * this work for additional information regarding copyright
- * ownership. Elasticsearch licenses this file to you under
- * the Apache License, Version 2.0 (the "License"); you may
- * not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *    http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing,
- * software distributed under the License is distributed on an
- * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
- * KIND, either express or implied.  See the License for the
- * specific language governing permissions and limitations
- * under the License.
- */
-package org.elasticsearch.search.aggregations.pipeline;
-
-import org.elasticsearch.common.bytes.BytesReference;
-import org.elasticsearch.common.io.stream.StreamInput;
-
-import java.io.IOException;
-import java.util.HashMap;
-import java.util.Map;
-
-import static java.util.Collections.emptyMap;
-import static java.util.Collections.unmodifiableMap;
-
-/**
- * A registry for all the dedicated streams in the aggregation module. This is to support dynamic addAggregation that
- * know how to stream themselves.
- */
-public class PipelineAggregatorStreams {
-    private static Map<BytesReference, Stream> streams = emptyMap();
-
-    /**
-     * A stream that knows how to read an aggregation from the input.
-     */
-    public interface Stream {
-        PipelineAggregator readResult(StreamInput in) throws IOException;
-    }
-
-    /**
-     * Registers the given stream and associate it with the given types.
-     *
-     * @param stream    The streams to register
-     * @param types     The types associated with the streams
-     */
-    public static synchronized void registerStream(Stream stream, BytesReference... types) {
-        Map<BytesReference, Stream> newStreams = new HashMap<>(streams);
-        for (BytesReference type : types) {
-            newStreams.put(type, stream);
-        }
-        streams = unmodifiableMap(newStreams);
-    }
-
-    /**
-     * Returns the stream that is registered for the given type
-     *
-     * @param   type The given type
-     * @return  The associated stream
-     */
-    public static Stream stream(BytesReference type) {
-        return streams.get(type);
-    }
-
-}
diff --git a/core/src/main/java/org/elasticsearch/search/aggregations/pipeline/SiblingPipelineAggregator.java b/core/src/main/java/org/elasticsearch/search/aggregations/pipeline/SiblingPipelineAggregator.java
index 79ec761b0e..b78691455d 100644
--- a/core/src/main/java/org/elasticsearch/search/aggregations/pipeline/SiblingPipelineAggregator.java
+++ b/core/src/main/java/org/elasticsearch/search/aggregations/pipeline/SiblingPipelineAggregator.java
@@ -36,11 +36,6 @@ import java.util.stream.Collectors;
 import java.util.stream.StreamSupport;
 
 public abstract class SiblingPipelineAggregator extends PipelineAggregator {
-
-    protected SiblingPipelineAggregator() { // NOCOMMIT remove me
-        super();
-    }
-
     protected SiblingPipelineAggregator(String name, String[] bucketsPaths, Map<String, Object> metaData) {
         super(name, bucketsPaths, metaData);
     }
@@ -83,7 +78,7 @@ public abstract class SiblingPipelineAggregator extends PipelineAggregator {
             return singleBucketAgg.create(new InternalAggregations(aggs));
         } else {
             throw new IllegalStateException("Aggregation [" + aggregation.getName() + "] must be a bucket aggregation ["
-                    + aggregation.type().name() + "]");
+                    + aggregation.getWriteableName() + "]");
         }
     }