RATIS-2099. Cache TermIndexImpl instead of using anonymous class (#1100)
diff --git a/ratis-server-api/src/main/java/org/apache/ratis/server/protocol/TermIndex.java b/ratis-server-api/src/main/java/org/apache/ratis/server/protocol/TermIndex.java
index 7def686..6a9bd1c 100644
--- a/ratis-server-api/src/main/java/org/apache/ratis/server/protocol/TermIndex.java
+++ b/ratis-server-api/src/main/java/org/apache/ratis/server/protocol/TermIndex.java
@@ -19,13 +19,21 @@
import org.apache.ratis.proto.RaftProtos.LogEntryProto;
import org.apache.ratis.proto.RaftProtos.TermIndexProto;
+import org.apache.ratis.thirdparty.com.google.common.cache.Cache;
+import org.apache.ratis.thirdparty.com.google.common.cache.CacheBuilder;
import java.util.Comparator;
import java.util.Optional;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.TimeUnit;
/** The term and the log index defined in the Raft consensus algorithm. */
public interface TermIndex extends Comparable<TermIndex> {
- TermIndex[] EMPTY_ARRAY = {};
+ /** An LRU Cache for {@link TermIndex} instances */
+ Cache<TermIndex, TermIndex> PRIVATE_CACHE = CacheBuilder.newBuilder()
+ .maximumSize(1 << 16)
+ .expireAfterAccess(1, TimeUnit.MINUTES)
+ .build();
/** @return the term. */
long getTerm();
@@ -60,7 +68,7 @@
/** @return a {@link TermIndex} object. */
static TermIndex valueOf(long term, long index) {
- return new TermIndex() {
+ final TermIndex key = new TermIndex() {
@Override
public long getTerm() {
return term;
@@ -98,5 +106,10 @@
return String.format("(t:%s, i:%s)", longToString(term), longToString(index));
}
};
+ try {
+ return PRIVATE_CACHE.get(key, () -> key);
+ } catch (ExecutionException e) {
+ throw new IllegalStateException("Failed to valueOf(" + term + ", " + index + "), key=" + key, e);
+ }
}
}
\ No newline at end of file
