use Objects.equals()

Author: Vladimir Kotal

opengrok-indexer/src/main/java/org/opengrok/indexer/history/History.java

@@ -133,8 +133,8 @@ public boolean equals(Object o) {
             return false;
         }
         History that = (History) o;
-        return this.getHistoryEntries().equals(that.getHistoryEntries()) &&
-                this.getRenamedFiles().equals(that.getRenamedFiles());
+        return Objects.equals(this.getHistoryEntries(), that.getHistoryEntries()) &&
+                Objects.equals(this.getRenamedFiles(), that.getRenamedFiles());
     }
 
     @Override

opengrok-indexer/src/main/java/org/opengrok/indexer/history/HistoryEntry.java

@@ -25,6 +25,7 @@
 
 import java.util.Collection;
 import java.util.Date;
+import java.util.Objects;
 import java.util.SortedSet;
 import java.util.TreeSet;
 import java.util.logging.Level;
@@ -217,14 +218,6 @@ public void stripTags() {
         tags = null;
     }
 
-    private boolean checkEquals(Object o1, Object o2) {
-        if (o1 != null && o2 != null) {
-            return o1.equals(o2);
-        }
-
-        return (o1 == null && o2 == null);
-    }
-
     private int getHashCode(Object o) {
         if (o == null) {
             return 0;
@@ -243,12 +236,12 @@ public boolean equals(Object o) {
         }
         HistoryEntry that = (HistoryEntry) o;
 
-        return checkEquals(this.getAuthor(), that.getAuthor()) &&
-                checkEquals(this.getRevision(), that.getRevision()) &&
-                checkEquals(this.getDate(), that.getDate()) &&
-                checkEquals(this.getMessage(), that.getMessage()) &&
-                checkEquals(this.getFiles(), that.getFiles()) &&
-                checkEquals(this.getTags(), that.getTags());
+        return Objects.equals(this.getAuthor(), that.getAuthor()) &&
+                Objects.equals(this.getRevision(), that.getRevision()) &&
+                Objects.equals(this.getDate(), that.getDate()) &&
+                Objects.equals(this.getMessage(), that.getMessage()) &&
+                Objects.equals(this.getFiles(), that.getFiles()) &&
+                Objects.equals(this.getTags(), that.getTags());
     }
 
     @Override