HBASE-23887 AdaptiveLRU cache (#2934)

Signed-off-by: Viraj Jasani <vjasani@apache.org>

dev-support/spotbugs-exclude.xml

@@ -247,4 +247,9 @@
     <Bug pattern="SC_START_IN_CTOR"/>
   </Match>
 
+  <Match>
+    <Class name="org.apache.hadoop.hbase.io.hfile.LruAdaptiveBlockCache"/>
+    <Bug pattern="SC_START_IN_CTOR"/>
+  </Match>
+
 </FindBugsFilter>

hbase-server/src/main/java/org/apache/hadoop/hbase/io/hfile/BlockCacheFactory.java

@@ -145,6 +145,8 @@ public final class BlockCacheFactory {
       return new LruBlockCache(cacheSize, blockSize, true, c);
     } else if (policy.equalsIgnoreCase("TinyLFU")) {
       return new TinyLfuBlockCache(cacheSize, blockSize, ForkJoinPool.commonPool(), c);
+    } else if (policy.equalsIgnoreCase("AdaptiveLRU")) {
+      return new LruAdaptiveBlockCache(cacheSize, blockSize, true, c);
     } else {
       throw new IllegalArgumentException("Unknown policy: " + policy);
     }