diff --git a/src/vm/jvm/runtime/org/raku/nqp/runtime/BootJavaInterop.java b/src/vm/jvm/runtime/org/raku/nqp/runtime/BootJavaInterop.java
index 2ebd5a924..eb40436f7 100644
--- a/src/vm/jvm/runtime/org/raku/nqp/runtime/BootJavaInterop.java
+++ b/src/vm/jvm/runtime/org/raku/nqp/runtime/BootJavaInterop.java
@@ -232,9 +232,9 @@ protected SixModelObject computeInterop(ThreadContext tc, Class<?> klass) {
 
         CompilationUnit adaptorUnit;
         try {
-            adaptorUnit = (CompilationUnit) adaptor.constructed.newInstance();
-        } catch (ReflectiveOperationException roe) {
-            throw new RuntimeException(roe);
+            adaptorUnit = (CompilationUnit) adaptor.constructed.getDeclaredConstructor().newInstance();
+        } catch (ReflectiveOperationException e) {
+            throw ExceptionHandling.dieInternal(tc, e);
         }
         adaptorUnit.initializeCompilationUnit(tc);
 
diff --git a/src/vm/jvm/runtime/org/raku/nqp/runtime/CompilationUnit.java b/src/vm/jvm/runtime/org/raku/nqp/runtime/CompilationUnit.java
index a0cd5c27f..131bb9644 100644
--- a/src/vm/jvm/runtime/org/raku/nqp/runtime/CompilationUnit.java
+++ b/src/vm/jvm/runtime/org/raku/nqp/runtime/CompilationUnit.java
@@ -63,9 +63,15 @@ public static void enterFromMain(Class<?> cuType, int entryCodeRefIdx, String[]
      */
     public static CompilationUnit setupCompilationUnit(ThreadContext tc, Class<?> cuType, boolean shared)
             throws InstantiationException, IllegalAccessException {
-        CompilationUnit cu = (CompilationUnit)cuType.newInstance();
-        cu.shared = shared;
-        cu.initializeCompilationUnit(tc);
+        CompilationUnit cu = null;
+        try {
+            cu = (CompilationUnit)cuType.getDeclaredConstructor().newInstance();
+            cu.shared = shared;
+            cu.initializeCompilationUnit(tc);
+        }
+        catch (ReflectiveOperationException e) {
+            throw ExceptionHandling.dieInternal(tc, e);
+        }
         return cu;
     }
 
diff --git a/src/vm/jvm/runtime/org/raku/nqp/runtime/LibraryLoader.java b/src/vm/jvm/runtime/org/raku/nqp/runtime/LibraryLoader.java
index a9677fb86..18f2d39e1 100644
--- a/src/vm/jvm/runtime/org/raku/nqp/runtime/LibraryLoader.java
+++ b/src/vm/jvm/runtime/org/raku/nqp/runtime/LibraryLoader.java
@@ -66,10 +66,15 @@ public void load(ThreadContext tc, byte[] buffer) {
     }
 
     private static void loadClass(ThreadContext tc, Class<?> c) throws Throwable {
-        CompilationUnit cu = (CompilationUnit)c.newInstance();
-        cu.shared = tc.gc.sharingHint;
-        cu.initializeCompilationUnit(tc);
-        cu.runLoadIfAvailable(tc);
+        try {
+            CompilationUnit cu = (CompilationUnit)c.getDeclaredConstructor().newInstance();
+            cu.shared = tc.gc.sharingHint;
+            cu.initializeCompilationUnit(tc);
+            cu.runLoadIfAvailable(tc);
+        }
+        catch (ReflectiveOperationException e) {
+            throw ExceptionHandling.dieInternal(tc, e);
+        }
     }
 
     private static Class<?> loadJar(byte[] buffer) throws Exception {
diff --git a/src/vm/jvm/runtime/org/raku/nqp/runtime/NativeCallOps.java b/src/vm/jvm/runtime/org/raku/nqp/runtime/NativeCallOps.java
index 392880e2e..3c07d16c8 100644
--- a/src/vm/jvm/runtime/org/raku/nqp/runtime/NativeCallOps.java
+++ b/src/vm/jvm/runtime/org/raku/nqp/runtime/NativeCallOps.java
@@ -115,7 +115,7 @@ public static SixModelObject call(SixModelObject returns, SixModelObject callObj
                     CPPStructREPRData repr_data = (CPPStructREPRData)returns.st.REPRData;
                     Class<?>    structClass     = repr_data.structureClass;
                     cppstruct                   = (CPPStructInstance)returns.st.REPR.allocate(tc, returns.st);
-                    cppstruct.storage           = (Structure)structClass.newInstance();
+                    cppstruct.storage           = (Structure)structClass.getDeclaredConstructor().newInstance();
                     cArgs[i]                    = cppstruct.storage;
                 }
                 else {
@@ -188,7 +188,9 @@ public static SixModelObject call(SixModelObject returns, SixModelObject callObj
                 return toNQPType(tc, call.ret_type, returns, returned);
             }
         }
-        catch (ControlException e) { throw e; }
+        catch (ControlException e) {
+            throw ExceptionHandling.dieInternal(tc, e);
+        }
         catch (Throwable t) {
             throw ExceptionHandling.dieInternal(tc, t);
         }
diff --git a/src/vm/jvm/runtime/org/raku/nqp/runtime/Ops.java b/src/vm/jvm/runtime/org/raku/nqp/runtime/Ops.java
index 912496d5b..d6e9b7619 100644
--- a/src/vm/jvm/runtime/org/raku/nqp/runtime/Ops.java
+++ b/src/vm/jvm/runtime/org/raku/nqp/runtime/Ops.java
@@ -56,6 +56,7 @@
 import java.util.Collections;
 import java.util.EnumSet;
 import java.util.HashMap;
+import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
 import java.util.Properties;
@@ -3804,8 +3805,10 @@ public static SixModelObject iter(SixModelObject agg, ThreadContext tc) {
         else if (agg.st.REPR instanceof VMHash) {
             SixModelObject iterType = tc.curFrame.codeRef.staticInfo.compUnit.hllConfig.hashIteratorType;
             VMIterInstance iter = (VMIterInstance)iterType.st.REPR.allocate(tc, iterType.st);
+            VMHashInstance hash = (VMHashInstance)agg;
+            Map<String, ?> storage = new HashMap< >(hash.storage);
             iter.target = agg;
-            iter.hashKeyIter = ((HashMap)((VMHashInstance)agg).storage.clone()).keySet().iterator();
+            iter.hashKeyIter = storage.keySet().iterator();
             iter.iterMode = VMIterInstance.MODE_HASH;
             return iter;
         }
@@ -7023,12 +7026,12 @@ public static long coerce_n2i(double in) {
             return Long.MIN_VALUE;
         }
         else {
-            return new Double(in).longValue();
+            return Double.valueOf(in).longValue();
         }
     }
 
     public static double coerce_i2n(long in) {
-        return new Long(in).doubleValue();
+        return Long.valueOf(in).doubleValue();
     }
 
     /* Long literal workaround. */
@@ -7387,7 +7390,7 @@ public static SixModelObject loadcompunit(SixModelObject obj, long compileeHLL,
         try {
             EvalResult res = (EvalResult)obj;
             Class<?> cuClass = tc.gc.byteClassLoader.defineClass(res.jc.name, res.jc.bytes);
-            res.cu = (CompilationUnit) cuClass.newInstance();
+            res.cu = (CompilationUnit) cuClass.getDeclaredConstructor().newInstance();
             if (compileeHLL != 0)
                 usecompileehllconfig(tc);
             res.cu.initializeCompilationUnit(tc);
@@ -7396,11 +7399,8 @@ public static SixModelObject loadcompunit(SixModelObject obj, long compileeHLL,
             res.jc = null;
             return obj;
         }
-        catch (ControlException e) {
-            throw e;
-        }
         catch (Exception e) {
-            throw new RuntimeException(e);
+            throw ExceptionHandling.dieInternal(tc, e);
         }
     }
     public static long iscompunit(SixModelObject obj, ThreadContext tc) {
diff --git a/src/vm/jvm/runtime/org/raku/nqp/sixmodel/reprs/CPPStruct.java b/src/vm/jvm/runtime/org/raku/nqp/sixmodel/reprs/CPPStruct.java
index 3f8b3a093..9874b9507 100644
--- a/src/vm/jvm/runtime/org/raku/nqp/sixmodel/reprs/CPPStruct.java
+++ b/src/vm/jvm/runtime/org/raku/nqp/sixmodel/reprs/CPPStruct.java
@@ -85,11 +85,10 @@ public SixModelObject allocate(ThreadContext tc, STable st) {
         CPPStructREPRData repr_data = (CPPStructREPRData) st.REPRData;
         obj.st = st;
         try {
-            obj.storage = (Structure) repr_data.structureClass.newInstance();
+            obj.storage = (Structure) repr_data.structureClass.getDeclaredConstructor().newInstance();
         }
-        catch (InstantiationException | IllegalAccessException e) {
-            e.printStackTrace();
-            throw new RuntimeException(e);
+        catch (ReflectiveOperationException e) {
+            throw ExceptionHandling.dieInternal(tc, e);
         }
         return obj;
     }
diff --git a/src/vm/jvm/runtime/org/raku/nqp/sixmodel/reprs/CStruct.java b/src/vm/jvm/runtime/org/raku/nqp/sixmodel/reprs/CStruct.java
index 0c647ca8e..7ccd47c2b 100644
--- a/src/vm/jvm/runtime/org/raku/nqp/sixmodel/reprs/CStruct.java
+++ b/src/vm/jvm/runtime/org/raku/nqp/sixmodel/reprs/CStruct.java
@@ -85,11 +85,10 @@ public SixModelObject allocate(ThreadContext tc, STable st) {
         CStructREPRData repr_data = (CStructREPRData) st.REPRData;
         obj.st = st;
         try {
-            obj.storage = (Structure) repr_data.structureClass.newInstance();
+            obj.storage = (Structure) repr_data.structureClass.getDeclaredConstructor().newInstance();
         }
-        catch (InstantiationException | IllegalAccessException e) {
-            e.printStackTrace();
-            throw new RuntimeException(e);
+        catch (ReflectiveOperationException e) {
+            throw ExceptionHandling.dieInternal(tc, e);
         }
         return obj;
     }
diff --git a/src/vm/jvm/runtime/org/raku/nqp/sixmodel/reprs/CUnion.java b/src/vm/jvm/runtime/org/raku/nqp/sixmodel/reprs/CUnion.java
index 1f3d1c296..bfb128b76 100644
--- a/src/vm/jvm/runtime/org/raku/nqp/sixmodel/reprs/CUnion.java
+++ b/src/vm/jvm/runtime/org/raku/nqp/sixmodel/reprs/CUnion.java
@@ -82,11 +82,10 @@ public SixModelObject allocate(ThreadContext tc, STable st) {
         CUnionREPRData repr_data = (CUnionREPRData) st.REPRData;
         obj.st = st;
         try {
-            obj.storage = (Union) repr_data.structureClass.newInstance();
+            obj.storage = (Union) repr_data.structureClass.getDeclaredConstructor().newInstance();
         }
-        catch (InstantiationException | IllegalAccessException e) {
-            e.printStackTrace();
-            throw new RuntimeException(e);
+        catch (ReflectiveOperationException e) {
+            throw ExceptionHandling.dieInternal(tc, e);
         }
         return obj;
     }
diff --git a/src/vm/jvm/runtime/org/raku/nqp/sixmodel/reprs/P6Opaque.java b/src/vm/jvm/runtime/org/raku/nqp/sixmodel/reprs/P6Opaque.java
index ea14f357e..2ce94959f 100644
--- a/src/vm/jvm/runtime/org/raku/nqp/sixmodel/reprs/P6Opaque.java
+++ b/src/vm/jvm/runtime/org/raku/nqp/sixmodel/reprs/P6Opaque.java
@@ -258,12 +258,15 @@ private void installJVMType(ThreadContext tc, STable st, List<AttrInfo> attrInfo
 
         ((P6OpaqueREPRData)st.REPRData).jvmClass = use;
         try {
-            ((P6OpaqueREPRData)st.REPRData).instance = (P6OpaqueBaseInstance)((P6OpaqueREPRData)st.REPRData).jvmClass.newInstance();
+            ((P6OpaqueREPRData)st.REPRData).instance =
+                (P6OpaqueBaseInstance)((P6OpaqueREPRData)st.REPRData).jvmClass.getDeclaredConstructor().newInstance();
         }
-        catch (InstantiationException | IllegalAccessException e) {
-            throw new RuntimeException(e);
+        catch (ReflectiveOperationException e) {
+            throw ExceptionHandling.dieInternal(tc, e);
+        }
+        finally {
+            ((P6OpaqueREPRData)st.REPRData).instance.st = st;
         }
-        ((P6OpaqueREPRData)st.REPRData).instance.st = st;
     }
 
     private Class<?> generateJVMClass(ThreadContext tc, List<AttrInfo> attrInfoList) {
diff --git a/src/vm/jvm/runtime/org/raku/nqp/sixmodel/reprs/P6OpaqueBaseInstance.java b/src/vm/jvm/runtime/org/raku/nqp/sixmodel/reprs/P6OpaqueBaseInstance.java
index ffc5581c0..d540d4b22 100644
--- a/src/vm/jvm/runtime/org/raku/nqp/sixmodel/reprs/P6OpaqueBaseInstance.java
+++ b/src/vm/jvm/runtime/org/raku/nqp/sixmodel/reprs/P6OpaqueBaseInstance.java
@@ -130,9 +130,7 @@ public SixModelObject cas_attribute_boxed(ThreadContext tc, SixModelObject class
         catch (Exception e) {
             throw ExceptionHandling.dieInternal(tc, e);
         }
-        finally {
-            return result == null ? Ops.createNull(tc) : result;
-        }
+        return result == null ? Ops.createNull(tc) : result;
     }
 
     @Override
@@ -161,9 +159,7 @@ public SixModelObject atomic_load_attribute_boxed(ThreadContext tc, SixModelObje
         catch (Exception e) {
             throw ExceptionHandling.dieInternal(tc, e);
         }
-        finally {
-            return result == null ? Ops.createNull(tc) : result;
-        }
+        return result == null ? Ops.createNull(tc) : result;
     }
 
     public SixModelObject posDelegate() {
diff --git a/src/vm/jvm/runtime/org/raku/nqp/sixmodel/reprs/VMIterInstance.java b/src/vm/jvm/runtime/org/raku/nqp/sixmodel/reprs/VMIterInstance.java
index 088f1546a..e5601f8c5 100644
--- a/src/vm/jvm/runtime/org/raku/nqp/sixmodel/reprs/VMIterInstance.java
+++ b/src/vm/jvm/runtime/org/raku/nqp/sixmodel/reprs/VMIterInstance.java
@@ -106,7 +106,7 @@ public boolean boolify() {
     public String key_s(ThreadContext tc) {
         switch (iterMode) {
         case MODE_ARRAY:
-            return new Long(idx).toString();
+            return Long.valueOf(idx).toString();
         case MODE_HASH:
             if (beforeStart || afterEnd)
                 throw ExceptionHandling.dieInternal(tc, "You have not advanced to the first item of the hash iterator, or have gone past the end");