Removal Streamable (#44647) (#44655)

This commit ends the grand adventure that was the
refactoring effort to migrate all usages of
Streamable to Writeable.

Closes #34389.

modules/reindex/src/test/java/org/elasticsearch/index/reindex/RoundTripTests.java

@@ -41,7 +41,7 @@ import static org.apache.lucene.util.TestUtil.randomSimpleString;
 import static org.elasticsearch.common.unit.TimeValue.parseTimeValue;
 
 /**
- * Round trip tests for all Streamable things declared in this plugin.
+ * Round trip tests for all {@link Writeable} things declared in this plugin.
  */
 public class RoundTripTests extends ESTestCase {
     public void testReindexRequest() throws IOException {

server/src/main/java/org/elasticsearch/common/io/stream/Streamable.java

@@ -1,57 +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.common.io.stream;
-
-import java.io.IOException;
-import java.util.function.Supplier;
-
-/**
- * Implementers can be written to a {@linkplain StreamOutput} and read from a {@linkplain StreamInput}. This allows them to be "thrown
- * across the wire" using Elasticsearch's internal protocol. If the implementer also implements equals and hashCode then a copy made by
- * serializing and deserializing must be equal and have the same hashCode. It isn't required that such a copy be entirely unchanged.
- *
- * Prefer implementing {@link Writeable} over implementing this interface where possible. Lots of code depends on this interface so this
- * isn't always possible.
- *
- * Implementers of this interface almost always declare a no arg constructor that is exclusively used for creating "empty" objects on which
- * you then call {@link #readFrom(StreamInput)}. Because {@linkplain #readFrom(StreamInput)} isn't part of the constructor the fields
- * on implementers cannot be final. It is these reasons that this interface has fallen out of favor compared to {@linkplain Writeable}.
- */
-public interface Streamable {
-    /**
-     * Set this object's fields from a {@linkplain StreamInput}.
-     */
-    default void readFrom(StreamInput in) throws IOException {
-        throw new UnsupportedOperationException("usage of Streamable is to be replaced by Writeable");
-    }
-
-    /**
-     * Write this object's fields to a {@linkplain StreamOutput}.
-     */
-    void writeTo(StreamOutput out) throws IOException;
-
-    static <T extends Streamable> Writeable.Reader<T> newWriteableReader(Supplier<T> supplier) {
-        return (StreamInput in) -> {
-            T request = supplier.get();
-            request.readFrom(in);
-            return request;
-        };
-    }
-}

server/src/main/java/org/elasticsearch/common/io/stream/Writeable.java

@@ -25,9 +25,6 @@ import java.io.IOException;
  * Implementers can be written to a {@linkplain StreamOutput} and read from a {@linkplain StreamInput}. This allows them to be "thrown
  * across the wire" using Elasticsearch's internal protocol. If the implementer also implements equals and hashCode then a copy made by
  * serializing and deserializing must be equal and have the same hashCode. It isn't required that such a copy be entirely unchanged.
- * <p>
- * Prefer implementing this interface over implementing {@link Streamable} where possible. Lots of code depends on {@linkplain Streamable}
- * so this isn't always possible.
  */
 public interface Writeable {
 

server/src/main/java/org/elasticsearch/tasks/TaskInfo.java

@@ -48,7 +48,7 @@ import static org.elasticsearch.common.xcontent.ConstructingObjectParser.optiona
  * <p>
  * Tasks are used for communication with transport actions. As a result, they can contain callback
  * references as well as mutable state. That makes it impractical to send tasks over transport channels
- * and use in APIs. Instead, immutable and streamable TaskInfo objects are used to represent
+ * and use in APIs. Instead, immutable and writeable TaskInfo objects are used to represent
  * snapshot information about currently running tasks.
  */
 public final class TaskInfo implements Writeable, ToXContentFragment {

server/src/main/java/org/elasticsearch/transport/TransportMessage.java

@@ -20,13 +20,10 @@
 package org.elasticsearch.transport;
 
 import org.elasticsearch.common.io.stream.StreamInput;
-import org.elasticsearch.common.io.stream.Streamable;
 import org.elasticsearch.common.io.stream.Writeable;
 import org.elasticsearch.common.transport.TransportAddress;
 
-import java.io.IOException;
-
-public abstract class TransportMessage implements Streamable, Writeable {
+public abstract class TransportMessage implements Writeable {
 
     private TransportAddress remoteAddress;
 
@@ -41,18 +38,11 @@ public abstract class TransportMessage implements Streamable, Writeable {
     /**
      * Constructs a new empty transport message
      */
-    public TransportMessage() {
-    }
+    public TransportMessage() {}
 
     /**
      * Constructs a new transport message with the data from the {@link StreamInput}. This is
      * currently a no-op
      */
-    public TransportMessage(StreamInput in) throws IOException {
-    }
-
-    @Override
-    public final void readFrom(StreamInput in) throws IOException {
-        throw new UnsupportedOperationException("usage of Streamable is to be replaced by Writeable");
-    }
+    public TransportMessage(StreamInput in) {}
 }

server/src/test/java/org/elasticsearch/action/admin/indices/settings/put/UpdateSettingsRequestTests.java

@@ -72,7 +72,7 @@ public class UpdateSettingsRequestTests extends AbstractXContentTestCase<UpdateS
     @Override
     protected void assertEqualInstances(UpdateSettingsRequest expectedInstance, UpdateSettingsRequest newInstance) {
         // here only the settings should be tested, as this test covers explicitly only the XContent parsing
-        // the rest of the request fields are tested by the StreamableTests
+        // the rest of the request fields are tested by the SerializingTests
         super.assertEqualInstances(new UpdateSettingsRequest(expectedInstance.settings()),
                 new UpdateSettingsRequest(newInstance.settings()));
     }

server/src/test/java/org/elasticsearch/common/io/stream/BytesStreamsTests.java

@@ -430,7 +430,7 @@ public class BytesStreamsTests extends ESTestCase {
         }
     }
 
-    public void testWriteStreamableList() throws IOException {
+    public void testWriteWriteableList() throws IOException {
         final int size = randomIntBetween(0, 5);
         final List<TestWriteable> expected = new ArrayList<>(size);