From 305b87b4b74483a4f7a5c24d209f2bef19256291 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Christoph=20B=C3=BCscher?= <cbuescher@posteo.de>
Date: Wed, 7 Feb 2018 09:33:21 +0100
Subject: [PATCH] Make internal Rounding fields final (#28532)

The fields in the internal rounding classes can be made final with very minor
adjustments to how they are read from a StreamInput.
---
 .../common/rounding/Rounding.java             | 53 ++++++++-----------
 1 file changed, 22 insertions(+), 31 deletions(-)

diff --git a/server/src/main/java/org/elasticsearch/common/rounding/Rounding.java b/server/src/main/java/org/elasticsearch/common/rounding/Rounding.java
index 808e59ef02a..93be4cc65e2 100644
--- a/server/src/main/java/org/elasticsearch/common/rounding/Rounding.java
+++ b/server/src/main/java/org/elasticsearch/common/rounding/Rounding.java
@@ -21,7 +21,7 @@ package org.elasticsearch.common.rounding;
 import org.elasticsearch.ElasticsearchException;
 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.unit.TimeValue;
 import org.joda.time.DateTimeField;
 import org.joda.time.DateTimeZone;
@@ -33,7 +33,7 @@ import java.util.Objects;
 /**
  * A strategy for rounding long values.
  */
-public abstract class Rounding implements Streamable {
+public abstract class Rounding implements Writeable {
 
     public abstract byte id();
 
@@ -107,13 +107,10 @@ public abstract class Rounding implements Streamable {
 
         static final byte ID = 1;
 
-        private DateTimeUnit unit;
-        private DateTimeField field;
-        private DateTimeZone timeZone;
-        private boolean unitRoundsToMidnight;
-
-        TimeUnitRounding() { // for serialization
-        }
+        private final DateTimeUnit unit;
+        private final DateTimeField field;
+        private final DateTimeZone timeZone;
+        private final boolean unitRoundsToMidnight;
 
         TimeUnitRounding(DateTimeUnit unit, DateTimeZone timeZone) {
             this.unit = unit;
@@ -122,6 +119,13 @@ public abstract class Rounding implements Streamable {
             this.timeZone = timeZone;
         }
 
+        TimeUnitRounding(StreamInput in) throws IOException {
+            unit = DateTimeUnit.resolve(in.readByte());
+            timeZone = DateTimeZone.forID(in.readString());
+            field = unit.field(timeZone);
+            unitRoundsToMidnight = field.getDurationField().getUnitMillis() > 60L * 60L * 1000L;
+        }
+
         @Override
         public byte id() {
             return ID;
@@ -237,14 +241,6 @@ public abstract class Rounding implements Streamable {
             return next;
         }
 
-        @Override
-        public void readFrom(StreamInput in) throws IOException {
-            unit = DateTimeUnit.resolve(in.readByte());
-            timeZone = DateTimeZone.forID(in.readString());
-            field = unit.field(timeZone);
-            unitRoundsToMidnight = field.getDurationField().getUnitMillis() > 60L * 60L * 1000L;
-        }
-
         @Override
         public void writeTo(StreamOutput out) throws IOException {
             out.writeByte(unit.id());
@@ -278,11 +274,8 @@ public abstract class Rounding implements Streamable {
 
         static final byte ID = 2;
 
-        private long interval;
-        private DateTimeZone timeZone;
-
-        TimeIntervalRounding() { // for serialization
-        }
+        private final long interval;
+        private final DateTimeZone timeZone;
 
         TimeIntervalRounding(long interval, DateTimeZone timeZone) {
             if (interval < 1)
@@ -291,6 +284,11 @@ public abstract class Rounding implements Streamable {
             this.timeZone = timeZone;
         }
 
+        TimeIntervalRounding(StreamInput in) throws IOException {
+            interval = in.readVLong();
+            timeZone = DateTimeZone.forID(in.readString());
+        }
+
         @Override
         public byte id() {
             return ID;
@@ -374,12 +372,6 @@ public abstract class Rounding implements Streamable {
             return timeZone.convertLocalToUTC(next, false);
         }
 
-        @Override
-        public void readFrom(StreamInput in) throws IOException {
-            interval = in.readVLong();
-            timeZone = DateTimeZone.forID(in.readString());
-        }
-
         @Override
         public void writeTo(StreamOutput out) throws IOException {
             out.writeVLong(interval);
@@ -415,11 +407,10 @@ public abstract class Rounding implements Streamable {
             Rounding rounding = null;
             byte id = in.readByte();
             switch (id) {
-                case TimeUnitRounding.ID: rounding = new TimeUnitRounding(); break;
-                case TimeIntervalRounding.ID: rounding = new TimeIntervalRounding(); break;
+                case TimeUnitRounding.ID: rounding = new TimeUnitRounding(in); break;
+                case TimeIntervalRounding.ID: rounding = new TimeIntervalRounding(in); break;
                 default: throw new ElasticsearchException("unknown rounding id [" + id + "]");
             }
-            rounding.readFrom(in);
             return rounding;
         }