ScriptStats to implement Writeable rather than Streamable

Also removed ScriptStats#add method which was unused

core/src/main/java/org/elasticsearch/action/admin/cluster/node/stats/NodeStats.java

@@ -219,7 +219,7 @@ public class NodeStats extends BaseNodeResponse implements ToXContent {
         transport = in.readOptionalWriteable(TransportStats::new);
         http = in.readOptionalWriteable(HttpStats::new);
         breaker = AllCircuitBreakerStats.readOptionalAllCircuitBreakerStats(in);
-        scriptStats = in.readOptionalStreamable(ScriptStats::new);
+        scriptStats = in.readOptionalWriteable(ScriptStats::new);
         discoveryStats = in.readOptionalStreamable(() -> new DiscoveryStats(null));
         ingestStats = in.readOptionalWriteable(IngestStats::new);
     }
@@ -242,7 +242,7 @@ public class NodeStats extends BaseNodeResponse implements ToXContent {
         out.writeOptionalWriteable(transport);
         out.writeOptionalWriteable(http);
         out.writeOptionalStreamable(breaker);
-        out.writeOptionalStreamable(scriptStats);
+        out.writeOptionalWriteable(scriptStats);
         out.writeOptionalStreamable(discoveryStats);
         out.writeOptionalWriteable(ingestStats);
     }

core/src/main/java/org/elasticsearch/script/ScriptStats.java

@@ -21,39 +21,22 @@ package org.elasticsearch.script;
 
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
-import org.elasticsearch.common.io.stream.Streamable;
+import org.elasticsearch.common.io.stream.Writeable;
 import org.elasticsearch.common.xcontent.ToXContent;
 import org.elasticsearch.common.xcontent.XContentBuilder;
 
 import java.io.IOException;
 
-public class ScriptStats implements Streamable, ToXContent {
-    private long compilations;
-    private long cacheEvictions;
-
-    public ScriptStats() {
-    }
+public class ScriptStats implements Writeable, ToXContent {
+    private final long compilations;
+    private final long cacheEvictions;
 
     public ScriptStats(long compilations, long cacheEvictions) {
         this.compilations = compilations;
         this.cacheEvictions = cacheEvictions;
     }
 
-    public void add(ScriptStats stats) {
-        this.compilations += stats.compilations;
-        this.cacheEvictions += stats.cacheEvictions;
-    }
-
-    public long getCompilations() {
-        return compilations;
-    }
-
-    public long getCacheEvictions() {
-        return cacheEvictions;
-    }
-
-    @Override
-    public void readFrom(StreamInput in) throws IOException {
+    public ScriptStats(StreamInput in) throws IOException {
         compilations = in.readVLong();
         cacheEvictions = in.readVLong();
     }
@@ -64,6 +47,14 @@ public class ScriptStats implements Streamable, ToXContent {
         out.writeVLong(cacheEvictions);
     }
 
+    public long getCompilations() {
+        return compilations;
+    }
+
+    public long getCacheEvictions() {
+        return cacheEvictions;
+    }
+
     @Override
     public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
         builder.startObject(Fields.SCRIPT_STATS);