Optimization: use Collections.emptyMap() in LoggingEvent

qos-ch · Apr 13, 2015 · 3d5cf2e · 3d5cf2e
1 parent 985257f
commit 3d5cf2e
Showing 1 changed file with 2 additions and 5 deletions.
diff --git a/logback-classic/src/main/java/ch/qos/logback/classic/spi/LoggingEvent.java b/logback-classic/src/main/java/ch/qos/logback/classic/spi/LoggingEvent.java
@@ -16,12 +16,10 @@
 import java.io.IOException;
 import java.io.ObjectOutputStream;
 import java.util.Collections;
-import java.util.HashMap;
 import java.util.Map;
 
 import org.slf4j.MDC;
 import org.slf4j.Marker;
-import org.slf4j.helpers.FormattingTuple;
 import org.slf4j.helpers.MessageFormatter;
 
 import ch.qos.logback.classic.Level;
@@ -93,7 +91,6 @@ public class LoggingEvent implements ILoggingEvent {
   private Marker marker;
 
   private Map<String, String> mdcPropertyMap;
-  private static final Map<String, String> CACHED_NULL_MAP = Collections.unmodifiableMap(new HashMap<String, String>());
 
   /**
    * The number of milliseconds elapsed from 1/1/1970 until logging event was
@@ -315,9 +312,9 @@ public Map<String, String> getMDCPropertyMap() {
       else
         mdcPropertyMap = mdc.getCopyOfContextMap();
     }
-    // mdcPropertyMap still null, use CACHED_NULL_MAP
+    // mdcPropertyMap still null, use emptyMap()
     if (mdcPropertyMap == null)
-      mdcPropertyMap = CACHED_NULL_MAP;
+      mdcPropertyMap = Collections.emptyMap();
 
     return mdcPropertyMap;
   }