[optimisation] Optimise for object identity equality

Author: adamretter

exist-core/src/main/java/org/exist/dom/persistent/Match.java

@@ -391,6 +391,10 @@ public static boolean matchListEquals(final Match m1, final Match m2) {
 
     @Override
     public boolean equals(final Object other) {
+        if (other == this) {
+            return true;
+        }
+
         if (other instanceof Match) {
             final Match om = (Match) other;
             return om.matchTerm != null
@@ -401,7 +405,6 @@ public boolean equals(final Object other) {
         }
     }
 
-
     /**
      * Used to sort matches. Terms are compared by their string
      * length to have the longest string first.

extensions/indexes/lucene/src/main/java/org/exist/indexing/lucene/LuceneMatch.java

@@ -93,6 +93,10 @@ public Facets getFacets() {
     // DW: missing hashCode() ?
     @Override
     public boolean equals(final Object other) {
+        if (other == this) {
+            return true;
+        }
+
         if (other instanceof LuceneMatch) {
             final LuceneMatch lm = (LuceneMatch) other;
             return getNodeId().equals(lm.getNodeId())