--- old/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/gc/z/ZAddressRangeMapForPageTable.java	2019-02-13 16:35:02.454271353 +0100
+++ new/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/gc/z/ZAddressRangeMapForPageTable.java	2019-02-13 16:35:02.078271366 +0100
@@ -54,15 +54,38 @@
         return mapField.getValue(addr);
     }
 
+    public long size() {
+        return ZGlobals.ZAddressOffsetMax >> AddressRangeShift;
+    }
+
     private long index_for_addr(Address addr) {
         long index = ZAddress.offset(addr) >> AddressRangeShift;
 
         return index;
     }
 
+    Address at(long index) {
+        return map().getAddressAt(index * VM.getVM().getBytesPerLong());
+    }
+
     Address get(Address addr) {
         long index = index_for_addr(addr);
+        return at(index);
+    }
 
-        return map().getAddressAt(index * VM.getVM().getBytesPerLong());
+    public class Iterator {
+        private long next = 0;
+
+        boolean hasNext() {
+            return next < size();
+        }
+
+        Address next() {
+            if (next >= size()) {
+                throw new RuntimeException("OOIBE");
+            }
+
+            return at(next++);
+        }
     }
 }