src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/utilities/HeapHprofBinWriter.java

@@ -30,10 +30,11 @@
 import sun.jvm.hotspot.debugger.*;
 import sun.jvm.hotspot.memory.*;
 import sun.jvm.hotspot.oops.*;
 import sun.jvm.hotspot.runtime.*;
 import sun.jvm.hotspot.classfile.*;
+import sun.jvm.hotspot.gc.z.ZCollectedHeap;
 
 /*
  * This class writes Java heap in hprof binary format. This format is
  * used by Heap Analysis Tool (HAT). The class is heavily influenced
  * by 'hprof_io.c' of 1.5 new hprof implementation.

@@ -391,10 +392,14 @@
         // open file stream and create buffered data output stream
         fos = new FileOutputStream(fileName);
         out = new DataOutputStream(new BufferedOutputStream(fos));
 
         VM vm = VM.getVM();
+        if (vm.getUniverse().heap() instanceof ZCollectedHeap) {
+            throw new RuntimeException("This operation is not supported with ZGC.");
+        }
+
         dbg = vm.getDebugger();
         objectHeap = vm.getObjectHeap();
 
         OBJ_ID_SIZE = (int) vm.getOopSize();