removed superfluous synchronization

source/net/yacy/kelondro/blob/HeapReader.java

@@ -363,9 +363,7 @@ public class HeapReader {
             log.severe("this.index == null in size(); closeDate=" + this.closeDate + ", now=" + new Date() + this.heapFile == null ? "" : (" file = " + this.heapFile.toString()));
             return 0;
         }
-        synchronized (this.index) {
-            return (this.index == null) ? 0 : this.index.size();
-        }
+        return (this.index == null) ? 0 : this.index.size();
     }
 
     public boolean isEmpty() {
@@ -374,9 +372,7 @@ public class HeapReader {
             log.severe("this.index == null in isEmpty(); closeDate=" + this.closeDate + ", now=" + new Date() + this.heapFile == null ? "" : (" file = " + this.heapFile.toString()));
             return true;
         }
-        synchronized (this.index) {
-            return this.index.isEmpty();
-        }
+        return this.index.isEmpty();
     }
 
     /**

source/net/yacy/kelondro/blob/MapDataMining.java

@@ -389,12 +389,12 @@ public class MapDataMining extends MapHeap {
     }
 
     @Override
-    public synchronized int size() {
+    public int size() {
         return super.size();
     }
 
     @Override
-    public synchronized boolean isEmpty() {
+    public boolean isEmpty() {
         return super.isEmpty();
     }
 

source/net/yacy/kelondro/blob/MapHeap.java

@@ -440,12 +440,12 @@ public class MapHeap implements Map<byte[], Map<String, String>> {
      * @return the number of entries in the table
      */
     @Override
-    public synchronized int size() {
+    public int size() {
         return (this.blob == null) ? 0 : this.blob.size();
     }
 
     @Override
-    public synchronized boolean isEmpty() {
+    public boolean isEmpty() {
         return (this.blob == null) ? true : this.blob.isEmpty();
     }