*Marshaller: get CacheSerilizer only once

CacheSerializer implementations are stateless (often implemented through
the enum-singleton pattern). There is no need to reach out for them for
each (de)serilize operation. As a bonus 'unchecked' doesn't have to
suppressed in 'read' operations.

Change-Id: I25d4ef94c52de9199029117abb73613bd841b1f5

src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/KeyWrapperMarshaller.java

diff --git a/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/KeyWrapperMarshaller.java b/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/KeyWrapperMarshaller.java
index 53de07c..1998c3d 100644
--- a/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/KeyWrapperMarshaller.java
+++ b/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/KeyWrapperMarshaller.java
@@ -13,6 +13,7 @@
 // limitations under the License.
 package com.googlesource.gerrit.modules.cache.chroniclemap;
 
+import com.google.gerrit.server.cache.serialize.CacheSerializer;
 import net.openhft.chronicle.bytes.Bytes;
 import net.openhft.chronicle.core.util.ReadResolvable;
 import net.openhft.chronicle.hash.serialization.BytesReader;
@@ -24,9 +25,11 @@
         ReadResolvable<KeyWrapperMarshaller<V>> {
 
   private final String name;
+  private final CacheSerializer<V> cacheSerializer;
 
   KeyWrapperMarshaller(String name) {
     this.name = name;
+    this.cacheSerializer = CacheSerializers.getKeySerializer(name);
   }
 
   @Override
@@ -34,13 +37,13 @@
     return new KeyWrapperMarshaller<>(name);
   }
 
-  @SuppressWarnings({"unchecked", "rawtypes"})
+  @SuppressWarnings("rawtypes")
   @Override
   public KeyWrapper<V> read(Bytes in, KeyWrapper<V> using) {
     int serializedLength = (int) in.readUnsignedInt();
     byte[] serialized = new byte[serializedLength];
     in.read(serialized, 0, serializedLength);
-    V v = (V) CacheSerializers.getKeySerializer(name).deserialize(serialized);
+    V v = cacheSerializer.deserialize(serialized);
     using = new KeyWrapper<>(v);
 
     return using;
@@ -49,7 +52,7 @@
   @SuppressWarnings("rawtypes")
   @Override
   public void write(Bytes out, KeyWrapper<V> toWrite) {
-    final byte[] serialized = CacheSerializers.getKeySerializer(name).serialize(toWrite.getValue());
+    final byte[] serialized = cacheSerializer.serialize(toWrite.getValue());
     out.writeUnsignedInt(serialized.length);
     out.write(serialized);
   }

src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/TimedValueMarshaller.java

diff --git a/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/TimedValueMarshaller.java b/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/TimedValueMarshaller.java
index f85f57e..f26366f 100644
--- a/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/TimedValueMarshaller.java
+++ b/src/main/java/com/googlesource/gerrit/modules/cache/chroniclemap/TimedValueMarshaller.java
@@ -13,6 +13,7 @@
 // limitations under the License.
 package com.googlesource.gerrit.modules.cache.chroniclemap;
 
+import com.google.gerrit.server.cache.serialize.CacheSerializer;
 import java.nio.ByteBuffer;
 import net.openhft.chronicle.bytes.Bytes;
 import net.openhft.chronicle.core.util.ReadResolvable;
@@ -25,9 +26,11 @@
         ReadResolvable<TimedValueMarshaller<V>> {
 
   private final String name;
+  private final CacheSerializer<V> cacheSerializer;
 
   TimedValueMarshaller(String name) {
     this.name = name;
+    this.cacheSerializer = CacheSerializers.getValueSerializer(name);
   }
 
   @Override
@@ -35,7 +38,7 @@
     return new TimedValueMarshaller<>(name);
   }
 
-  @SuppressWarnings({"rawtypes", "unchecked"})
+  @SuppressWarnings("rawtypes")
   @Override
   public TimedValue<V> read(Bytes in, TimedValue<V> using) {
     long initialPosition = in.readPosition();
@@ -57,7 +60,7 @@
     // Deserialize object V (remaining bytes)
     byte[] serializedV = new byte[vLength];
     in.read(serializedV, 0, vLength);
-    V v = (V) CacheSerializers.getValueSerializer(name).deserialize(serializedV);
+    V v = cacheSerializer.deserialize(serializedV);
 
     using = new TimedValue<>(v, created);
 
@@ -67,7 +70,7 @@
   @SuppressWarnings("rawtypes")
   @Override
   public void write(Bytes out, TimedValue<V> toWrite) {
-    byte[] serialized = CacheSerializers.getValueSerializer(name).serialize(toWrite.getValue());
+    byte[] serialized = cacheSerializer.serialize(toWrite.getValue());
 
     // Serialize as follows:
     // created | length of serialized V | serialized value V