diff --git a/runtime/openjdkjvmti/OpenjdkJvmTi.cc b/runtime/openjdkjvmti/OpenjdkJvmTi.cc
index c32f8b7..94afd2f 100644
--- a/runtime/openjdkjvmti/OpenjdkJvmTi.cc
+++ b/runtime/openjdkjvmti/OpenjdkJvmTi.cc
@@ -1190,7 +1190,7 @@
                                     reinterpret_cast<uint8_t*>(dex_file),
                                     &error);
     if (ret != OK) {
-      LOG(ERROR) << "FAILURE TO REDEFINE " << error;
+      LOG(WARNING) << "FAILURE TO REDEFINE " << error;
     }
     return ret;
   }
diff --git a/runtime/openjdkjvmti/ti_redefine.cc b/runtime/openjdkjvmti/ti_redefine.cc
index 926819d..6b0e9c8 100644
--- a/runtime/openjdkjvmti/ti_redefine.cc
+++ b/runtime/openjdkjvmti/ti_redefine.cc
@@ -37,6 +37,8 @@
 
 #include "art_jvmti.h"
 #include "base/logging.h"
+#include "dex_file.h"
+#include "dex_file_types.h"
 #include "events-inl.h"
 #include "gc/allocation_listener.h"
 #include "gc/heap.h"
@@ -542,6 +544,118 @@
   i->ReJitEverything("libOpenJkdJvmti - Class Redefinition");
 }
 
+bool Redefiner::CheckClass() {
+  // TODO Might just want to put it in a ObjPtr and NoSuspend assert.
+  art::StackHandleScope<1> hs(self_);
+  // Easy check that only 1 class def is present.
+  if (dex_file_->NumClassDefs() != 1) {
+    RecordFailure(ERR(ILLEGAL_ARGUMENT),
+                  StringPrintf("Expected 1 class def in dex file but found %d",
+                               dex_file_->NumClassDefs()));
+    return false;
+  }
+  // Get the ClassDef from the new DexFile.
+  // Since the dex file has only a single class def the index is always 0.
+  const art::DexFile::ClassDef& def = dex_file_->GetClassDef(0);
+  // Get the class as it is now.
+  art::Handle<art::mirror::Class> current_class(hs.NewHandle(GetMirrorClass()));
+
+  // Check the access flags didn't change.
+  if (def.GetJavaAccessFlags() != (current_class->GetAccessFlags() & art::kAccValidClassFlags)) {
+    RecordFailure(ERR(UNSUPPORTED_REDEFINITION_CLASS_MODIFIERS_CHANGED),
+                  "Cannot change modifiers of class by redefinition");
+    return false;
+  }
+
+  // Check class name.
+  // These should have been checked by the dexfile verifier on load.
+  DCHECK_NE(def.class_idx_, art::dex::TypeIndex::Invalid()) << "Invalid type index";
+  const char* descriptor = dex_file_->StringByTypeIdx(def.class_idx_);
+  DCHECK(descriptor != nullptr) << "Invalid dex file structure!";
+  if (!current_class->DescriptorEquals(descriptor)) {
+    std::string storage;
+    RecordFailure(ERR(NAMES_DONT_MATCH),
+                  StringPrintf("expected file to contain class called '%s' but found '%s'!",
+                               current_class->GetDescriptor(&storage),
+                               descriptor));
+    return false;
+  }
+  if (current_class->IsObjectClass()) {
+    if (def.superclass_idx_ != art::dex::TypeIndex::Invalid()) {
+      RecordFailure(ERR(UNSUPPORTED_REDEFINITION_HIERARCHY_CHANGED), "Superclass added!");
+      return false;
+    }
+  } else {
+    const char* super_descriptor = dex_file_->StringByTypeIdx(def.superclass_idx_);
+    DCHECK(descriptor != nullptr) << "Invalid dex file structure!";
+    if (!current_class->GetSuperClass()->DescriptorEquals(super_descriptor)) {
+      RecordFailure(ERR(UNSUPPORTED_REDEFINITION_HIERARCHY_CHANGED), "Superclass changed");
+      return false;
+    }
+  }
+  const art::DexFile::TypeList* interfaces = dex_file_->GetInterfacesList(def);
+  if (interfaces == nullptr) {
+    if (current_class->NumDirectInterfaces() != 0) {
+      RecordFailure(ERR(UNSUPPORTED_REDEFINITION_HIERARCHY_CHANGED), "Interfaces added");
+      return false;
+    }
+  } else {
+    DCHECK(!current_class->IsProxyClass());
+    const art::DexFile::TypeList* current_interfaces = current_class->GetInterfaceTypeList();
+    if (current_interfaces == nullptr || current_interfaces->Size() != interfaces->Size()) {
+      RecordFailure(ERR(UNSUPPORTED_REDEFINITION_HIERARCHY_CHANGED), "Interfaces added or removed");
+      return false;
+    }
+    // The order of interfaces is (barely) meaningful so we error if it changes.
+    const art::DexFile& orig_dex_file = current_class->GetDexFile();
+    for (uint32_t i = 0; i < interfaces->Size(); i++) {
+      if (strcmp(
+            dex_file_->StringByTypeIdx(interfaces->GetTypeItem(i).type_idx_),
+            orig_dex_file.StringByTypeIdx(current_interfaces->GetTypeItem(i).type_idx_)) != 0) {
+        RecordFailure(ERR(UNSUPPORTED_REDEFINITION_HIERARCHY_CHANGED),
+                      "Interfaces changed or re-ordered");
+        return false;
+      }
+    }
+  }
+  LOG(WARNING) << "No verification is done on annotations of redefined classes.";
+
+  return true;
+}
+
+// TODO Move this to use IsRedefinable when that function is made.
+bool Redefiner::CheckRedefinable() {
+  art::ObjPtr<art::mirror::Class> klass(GetMirrorClass());
+  if (klass->IsPrimitive()) {
+    RecordFailure(ERR(UNMODIFIABLE_CLASS),
+                  "Modification of primitive classes is not supported");
+    return false;
+  } else if (klass->IsInterface()) {
+    RecordFailure(ERR(UNMODIFIABLE_CLASS),
+                  "Modification of Interface classes is currently not supported");
+    return false;
+  } else if (klass->IsArrayClass()) {
+    RecordFailure(ERR(UNMODIFIABLE_CLASS),
+                  "Modification of Array classes is not supported");
+    return false;
+  } else if (klass->IsProxyClass()) {
+    RecordFailure(ERR(UNMODIFIABLE_CLASS),
+                  "Modification of proxy classes is not supported");
+    return false;
+  }
+
+  // TODO We should check if the class has non-obsoletable methods on the stack
+  LOG(WARNING) << "presence of non-obsoletable methods on stacks is not currently checked";
+  return true;
+}
+
+bool Redefiner::CheckRedefinitionIsValid() {
+  return CheckRedefinable() &&
+      CheckClass() &&
+      CheckSameFields() &&
+      CheckSameMethods();
+}
+
 jvmtiError Redefiner::Run() {
   art::StackHandleScope<5> hs(self_);
   // TODO We might want to have a global lock (or one based on the class being redefined at least)
@@ -552,7 +666,7 @@
   // doing a try loop. The other allocations we need to ensure that nothing has changed in the time
   // between allocating them and pausing all threads before we can update them so we need to do a
   // try loop.
-  if (!EnsureRedefinitionIsValid() || !EnsureClassAllocationsFinished()) {
+  if (!CheckRedefinitionIsValid() || !EnsureClassAllocationsFinished()) {
     return result_;
   }
   art::MutableHandle<art::mirror::ClassLoader> source_class_loader(
diff --git a/runtime/openjdkjvmti/ti_redefine.h b/runtime/openjdkjvmti/ti_redefine.h
index 9d23ce4..d6bccb4 100644
--- a/runtime/openjdkjvmti/ti_redefine.h
+++ b/runtime/openjdkjvmti/ti_redefine.h
@@ -152,14 +152,29 @@
 
   void RecordFailure(jvmtiError result, const std::string& error_msg);
 
-  // TODO Actually write this.
   // This will check that no constraints are violated (more than 1 class in dex file, any changes in
   // number/declaration of methods & fields, changes in access flags, etc.)
-  bool EnsureRedefinitionIsValid() {
-    LOG(WARNING) << "Redefinition is not checked for validity currently";
+  bool CheckRedefinitionIsValid() REQUIRES_SHARED(art::Locks::mutator_lock_);
+
+  // Checks that the class can even be redefined.
+  bool CheckRedefinable() REQUIRES_SHARED(art::Locks::mutator_lock_);
+
+  // Checks that the dex file does not add/remove methods.
+  bool CheckSameMethods() REQUIRES_SHARED(art::Locks::mutator_lock_) {
+    LOG(WARNING) << "methods are not checked for modification currently";
     return true;
   }
 
+  // Checks that the dex file does not modify fields
+  bool CheckSameFields() REQUIRES_SHARED(art::Locks::mutator_lock_) {
+    LOG(WARNING) << "Fields are not checked for modification currently";
+    return true;
+  }
+
+  // Checks that the dex file contains only the single expected class and that the top-level class
+  // data has not been modified in an incompatible manner.
+  bool CheckClass() REQUIRES_SHARED(art::Locks::mutator_lock_);
+
   bool UpdateJavaDexFile(art::ObjPtr<art::mirror::Object> java_dex_file,
                          art::ObjPtr<art::mirror::LongArray> new_cookie,
                          /*out*/art::ObjPtr<art::mirror::LongArray>* original_cookie)
diff --git a/test/921-hello-failure/build b/test/921-hello-failure/build
new file mode 100755
index 0000000..898e2e5
--- /dev/null
+++ b/test/921-hello-failure/build
@@ -0,0 +1,17 @@
+#!/bin/bash
+#
+# Copyright 2016 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+./default-build "$@" --experimental agents
diff --git a/test/921-hello-failure/expected.txt b/test/921-hello-failure/expected.txt
new file mode 100644
index 0000000..e2665ef
--- /dev/null
+++ b/test/921-hello-failure/expected.txt
@@ -0,0 +1,15 @@
+hello - NewName
+Transformation error : java.lang.Exception(Failed to redefine class <LTransform;> due to JVMTI_ERROR_NAMES_DONT_MATCH)
+hello - NewName
+hello - DifferentAccess
+Transformation error : java.lang.Exception(Failed to redefine class <LTransform;> due to JVMTI_ERROR_UNSUPPORTED_REDEFINITION_CLASS_MODIFIERS_CHANGED)
+hello - DifferentAccess
+hello2 - NewInterface
+Transformation error : java.lang.Exception(Failed to redefine class <LTransform2;> due to JVMTI_ERROR_UNSUPPORTED_REDEFINITION_HIERARCHY_CHANGED)
+hello2 - NewInterface
+hello2 - MissingInterface
+Transformation error : java.lang.Exception(Failed to redefine class <LTransform2;> due to JVMTI_ERROR_UNSUPPORTED_REDEFINITION_HIERARCHY_CHANGED)
+hello2 - MissingInterface
+hello2 - ReorderInterface
+Transformation error : java.lang.Exception(Failed to redefine class <LTransform2;> due to JVMTI_ERROR_UNSUPPORTED_REDEFINITION_HIERARCHY_CHANGED)
+hello2 - ReorderInterface
diff --git a/test/921-hello-failure/info.txt b/test/921-hello-failure/info.txt
new file mode 100644
index 0000000..9d241c7
--- /dev/null
+++ b/test/921-hello-failure/info.txt
@@ -0,0 +1,7 @@
+Tests for redefinition failure modes.
+
+Tests
+----
+
+- NewName: The name of the class is changed
+- DifferentAccess: Class access is changed from <default> to 'public'
diff --git a/test/921-hello-failure/run b/test/921-hello-failure/run
new file mode 100755
index 0000000..3ef4832
--- /dev/null
+++ b/test/921-hello-failure/run
@@ -0,0 +1,20 @@
+#!/bin/bash
+#
+# Copyright 2016 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+
+./default-run "$@" --experimental agents \
+                   --experimental runtime-plugins \
+                   --jvmti
diff --git a/test/921-hello-failure/src/DifferentAccess.java b/test/921-hello-failure/src/DifferentAccess.java
new file mode 100644
index 0000000..d4b16e0
--- /dev/null
+++ b/test/921-hello-failure/src/DifferentAccess.java
@@ -0,0 +1,57 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import java.util.Base64;
+
+class DifferentAccess {
+  // The following is a base64 encoding of the following class.
+  // public class NotTransform {
+  //   public void sayHi(String name) {
+  //     throw new Error("Should not be called!");
+  //   }
+  // }
+  private static final byte[] CLASS_BYTES = Base64.getDecoder().decode(
+    "yv66vgAAADQAFQoABgAPBwAQCAARCgACABIHABMHABQBAAY8aW5pdD4BAAMoKVYBAARDb2RlAQAP" +
+    "TGluZU51bWJlclRhYmxlAQAFc2F5SGkBABUoTGphdmEvbGFuZy9TdHJpbmc7KVYBAApTb3VyY2VG" +
+    "aWxlAQAOVHJhbnNmb3JtLmphdmEMAAcACAEAD2phdmEvbGFuZy9FcnJvcgEAFVNob3VsZCBub3Qg" +
+    "YmUgY2FsbGVkIQwABwAMAQAJVHJhbnNmb3JtAQAQamF2YS9sYW5nL09iamVjdAAhAAUABgAAAAAA" +
+    "AgABAAcACAABAAkAAAAdAAEAAQAAAAUqtwABsQAAAAEACgAAAAYAAQAAAAEAAQALAAwAAQAJAAAA" +
+    "IgADAAIAAAAKuwACWRIDtwAEvwAAAAEACgAAAAYAAQAAAAMAAQANAAAAAgAO");
+  private static final byte[] DEX_BYTES = Base64.getDecoder().decode(
+    "ZGV4CjAzNQANVRT7zleRLG4E5DhtK7OtoDxZlUQMI5eQAgAAcAAAAHhWNBIAAAAAAAAAAPwBAAAL" +
+    "AAAAcAAAAAUAAACcAAAAAgAAALAAAAAAAAAAAAAAAAQAAADIAAAAAQAAAOgAAACIAQAACAEAAEoB" +
+    "AABSAQAAXwEAAHIBAACGAQAAmgEAALEBAADBAQAAxAEAAMgBAADcAQAAAQAAAAIAAAADAAAABAAA" +
+    "AAcAAAAHAAAABAAAAAAAAAAIAAAABAAAAEQBAAAAAAAAAAAAAAAAAQAKAAAAAQABAAAAAAACAAAA" +
+    "AAAAAAAAAAABAAAAAgAAAAAAAAAGAAAAAAAAAO4BAAAAAAAAAQABAAEAAADjAQAABAAAAHAQAwAA" +
+    "AA4ABAACAAIAAADoAQAACQAAACIAAQAbAQUAAABwIAIAEAAnAAAAAQAAAAMABjxpbml0PgALTFRy" +
+    "YW5zZm9ybTsAEUxqYXZhL2xhbmcvRXJyb3I7ABJMamF2YS9sYW5nL09iamVjdDsAEkxqYXZhL2xh" +
+    "bmcvU3RyaW5nOwAVU2hvdWxkIG5vdCBiZSBjYWxsZWQhAA5UcmFuc2Zvcm0uamF2YQABVgACVkwA" +
+    "EmVtaXR0ZXI6IGphY2stNC4yMAAFc2F5SGkAAQAHDgADAQAHDgAAAAEBAIGABIgCAQGgAgwAAAAA" +
+    "AAAAAQAAAAAAAAABAAAACwAAAHAAAAACAAAABQAAAJwAAAADAAAAAgAAALAAAAAFAAAABAAAAMgA" +
+    "AAAGAAAAAQAAAOgAAAABIAAAAgAAAAgBAAABEAAAAQAAAEQBAAACIAAACwAAAEoBAAADIAAAAgAA" +
+    "AOMBAAAAIAAAAQAAAO4BAAAAEAAAAQAAAPwBAAA=");
+
+  public static void doTest(Transform t) {
+    t.sayHi("DifferentAccess");
+    try {
+      Main.doCommonClassRedefinition(Transform.class, CLASS_BYTES, DEX_BYTES);
+    } catch (Exception e) {
+      System.out.println(
+          "Transformation error : " + e.getClass().getName() + "(" + e.getMessage() + ")");
+    }
+    t.sayHi("DifferentAccess");
+  }
+}
diff --git a/test/921-hello-failure/src/Iface1.java b/test/921-hello-failure/src/Iface1.java
new file mode 100644
index 0000000..f53275a
--- /dev/null
+++ b/test/921-hello-failure/src/Iface1.java
@@ -0,0 +1,19 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+interface Iface1 {
+  void sayHi(String s);
+}
diff --git a/test/921-hello-failure/src/Iface2.java b/test/921-hello-failure/src/Iface2.java
new file mode 100644
index 0000000..54cdd90
--- /dev/null
+++ b/test/921-hello-failure/src/Iface2.java
@@ -0,0 +1,19 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+interface Iface2 {
+  void sayHi(String s);
+}
diff --git a/test/921-hello-failure/src/Iface3.java b/test/921-hello-failure/src/Iface3.java
new file mode 100644
index 0000000..819134d
--- /dev/null
+++ b/test/921-hello-failure/src/Iface3.java
@@ -0,0 +1,19 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+interface Iface3 {
+  void sayHi(String s);
+}
diff --git a/test/921-hello-failure/src/Main.java b/test/921-hello-failure/src/Main.java
new file mode 100644
index 0000000..69c48e2
--- /dev/null
+++ b/test/921-hello-failure/src/Main.java
@@ -0,0 +1,32 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+public class Main {
+
+  public static void main(String[] args) {
+    System.loadLibrary(args[1]);
+    NewName.doTest(new Transform());
+    DifferentAccess.doTest(new Transform());
+    NewInterface.doTest(new Transform2());
+    MissingInterface.doTest(new Transform2());
+    ReorderInterface.doTest(new Transform2());
+  }
+
+  // Transforms the class. This throws an exception if something goes wrong.
+  public static native void doCommonClassRedefinition(Class<?> target,
+                                                      byte[] classfile,
+                                                      byte[] dexfile) throws Exception;
+}
diff --git a/test/921-hello-failure/src/MissingInterface.java b/test/921-hello-failure/src/MissingInterface.java
new file mode 100644
index 0000000..d17a6de
--- /dev/null
+++ b/test/921-hello-failure/src/MissingInterface.java
@@ -0,0 +1,58 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import java.util.Base64;
+
+class MissingInterface {
+  // The following is a base64 encoding of the following class.
+  // class Transform2 implements Iface1 {
+  //   public void sayHi(String name) {
+  //     throw new Error("Should not be called!");
+  //   }
+  // }
+  private static final byte[] CLASS_BYTES = Base64.getDecoder().decode(
+      "yv66vgAAADQAFwoABgAQBwARCAASCgACABMHABQHABUHABYBAAY8aW5pdD4BAAMoKVYBAARDb2Rl" +
+      "AQAPTGluZU51bWJlclRhYmxlAQAFc2F5SGkBABUoTGphdmEvbGFuZy9TdHJpbmc7KVYBAApTb3Vy" +
+      "Y2VGaWxlAQAPVHJhbnNmb3JtMi5qYXZhDAAIAAkBAA9qYXZhL2xhbmcvRXJyb3IBABVTaG91bGQg" +
+      "bm90IGJlIGNhbGxlZCEMAAgADQEAClRyYW5zZm9ybTIBABBqYXZhL2xhbmcvT2JqZWN0AQAGSWZh" +
+      "Y2UxACAABQAGAAEABwAAAAIAAAAIAAkAAQAKAAAAHQABAAEAAAAFKrcAAbEAAAABAAsAAAAGAAEA" +
+      "AAABAAEADAANAAEACgAAACIAAwACAAAACrsAAlkSA7cABL8AAAABAAsAAAAGAAEAAAADAAEADgAA" +
+      "AAIADw==");
+  private static final byte[] DEX_BYTES = Base64.getDecoder().decode(
+      "ZGV4CjAzNQDiWVay8/Z0/tXQaTTI+QtwTM65gRJVMOusAgAAcAAAAHhWNBIAAAAAAAAAABgCAAAM" +
+      "AAAAcAAAAAYAAACgAAAAAgAAALgAAAAAAAAAAAAAAAQAAADQAAAAAQAAAPAAAACcAQAAEAEAAFoB" +
+      "AABiAQAAbAEAAHoBAACNAQAAoQEAALUBAADMAQAA3QEAAOABAADkAQAA+AEAAAEAAAACAAAAAwAA" +
+      "AAQAAAAFAAAACAAAAAgAAAAFAAAAAAAAAAkAAAAFAAAAVAEAAAEAAAAAAAAAAQABAAsAAAACAAEA" +
+      "AAAAAAMAAAAAAAAAAQAAAAAAAAADAAAATAEAAAcAAAAAAAAACgIAAAAAAAABAAEAAQAAAP8BAAAE" +
+      "AAAAcBADAAAADgAEAAIAAgAAAAQCAAAJAAAAIgACABsBBgAAAHAgAgAQACcAAAABAAAAAAAAAAEA" +
+      "AAAEAAY8aW5pdD4ACExJZmFjZTE7AAxMVHJhbnNmb3JtMjsAEUxqYXZhL2xhbmcvRXJyb3I7ABJM" +
+      "amF2YS9sYW5nL09iamVjdDsAEkxqYXZhL2xhbmcvU3RyaW5nOwAVU2hvdWxkIG5vdCBiZSBjYWxs" +
+      "ZWQhAA9UcmFuc2Zvcm0yLmphdmEAAVYAAlZMABJlbWl0dGVyOiBqYWNrLTQuMjAABXNheUhpAAEA" +
+      "Bw4AAwEABw4AAAABAQCAgASQAgEBqAIMAAAAAAAAAAEAAAAAAAAAAQAAAAwAAABwAAAAAgAAAAYA" +
+      "AACgAAAAAwAAAAIAAAC4AAAABQAAAAQAAADQAAAABgAAAAEAAADwAAAAASAAAAIAAAAQAQAAARAA" +
+      "AAIAAABMAQAAAiAAAAwAAABaAQAAAyAAAAIAAAD/AQAAACAAAAEAAAAKAgAAABAAAAEAAAAYAgAA");
+
+  public static void doTest(Transform2 t) {
+    t.sayHi("MissingInterface");
+    try {
+      Main.doCommonClassRedefinition(Transform2.class, CLASS_BYTES, DEX_BYTES);
+    } catch (Exception e) {
+      System.out.println(
+          "Transformation error : " + e.getClass().getName() + "(" + e.getMessage() + ")");
+    }
+    t.sayHi("MissingInterface");
+  }
+}
diff --git a/test/921-hello-failure/src/NewInterface.java b/test/921-hello-failure/src/NewInterface.java
new file mode 100644
index 0000000..fe77222
--- /dev/null
+++ b/test/921-hello-failure/src/NewInterface.java
@@ -0,0 +1,59 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import java.util.Base64;
+
+class NewInterface {
+  // The following is a base64 encoding of the following class.
+  // class Transform2 implements Iface1, Iface2, Iface3 {
+  //   public void sayHi(String name) {
+  //     throw new Error("Should not be called!");
+  //   }
+  // }
+  private static final byte[] CLASS_BYTES = Base64.getDecoder().decode(
+    "yv66vgAAADQAGwoABgASBwATCAAUCgACABUHABYHABcHABgHABkHABoBAAY8aW5pdD4BAAMoKVYB" +
+    "AARDb2RlAQAPTGluZU51bWJlclRhYmxlAQAFc2F5SGkBABUoTGphdmEvbGFuZy9TdHJpbmc7KVYB" +
+    "AApTb3VyY2VGaWxlAQAPVHJhbnNmb3JtMi5qYXZhDAAKAAsBAA9qYXZhL2xhbmcvRXJyb3IBABVT" +
+    "aG91bGQgbm90IGJlIGNhbGxlZCEMAAoADwEAClRyYW5zZm9ybTIBABBqYXZhL2xhbmcvT2JqZWN0" +
+    "AQAGSWZhY2UxAQAGSWZhY2UyAQAGSWZhY2UzACAABQAGAAMABwAIAAkAAAACAAAACgALAAEADAAA" +
+    "AB0AAQABAAAABSq3AAGxAAAAAQANAAAABgABAAAAAQABAA4ADwABAAwAAAAiAAMAAgAAAAq7AAJZ" +
+    "EgO3AAS/AAAAAQANAAAABgABAAAAAwABABAAAAACABE=");
+  private static final byte[] DEX_BYTES = Base64.getDecoder().decode(
+    "ZGV4CjAzNQCBWnko4SMXeuXSO3fGJBp0WSlc0HLRr63UAgAAcAAAAHhWNBIAAAAAAAAAAEACAAAO" +
+    "AAAAcAAAAAgAAACoAAAAAgAAAMgAAAAAAAAAAAAAAAQAAADgAAAAAQAAAAABAAC0AQAAIAEAAG4B" +
+    "AAB2AQAAgAEAAIoBAACUAQAAogEAALUBAADJAQAA3QEAAPQBAAAFAgAACAIAAAwCAAAgAgAAAQAA" +
+    "AAIAAAADAAAABAAAAAUAAAAGAAAABwAAAAoAAAAKAAAABwAAAAAAAAALAAAABwAAAGgBAAADAAAA" +
+    "AAAAAAMAAQANAAAABAABAAAAAAAFAAAAAAAAAAMAAAAAAAAABQAAAFwBAAAJAAAAAAAAADICAAAA" +
+    "AAAAAQABAAEAAAAnAgAABAAAAHAQAwAAAA4ABAACAAIAAAAsAgAACQAAACIABAAbAQgAAABwIAIA" +
+    "EAAnAAAAAwAAAAAAAQACAAAAAQAAAAYABjxpbml0PgAITElmYWNlMTsACExJZmFjZTI7AAhMSWZh" +
+    "Y2UzOwAMTFRyYW5zZm9ybTI7ABFMamF2YS9sYW5nL0Vycm9yOwASTGphdmEvbGFuZy9PYmplY3Q7" +
+    "ABJMamF2YS9sYW5nL1N0cmluZzsAFVNob3VsZCBub3QgYmUgY2FsbGVkIQAPVHJhbnNmb3JtMi5q" +
+    "YXZhAAFWAAJWTAASZW1pdHRlcjogamFjay00LjIwAAVzYXlIaQABAAcOAAMBAAcOAAAAAQEAgIAE" +
+    "oAIBAbgCDAAAAAAAAAABAAAAAAAAAAEAAAAOAAAAcAAAAAIAAAAIAAAAqAAAAAMAAAACAAAAyAAA" +
+    "AAUAAAAEAAAA4AAAAAYAAAABAAAAAAEAAAEgAAACAAAAIAEAAAEQAAACAAAAXAEAAAIgAAAOAAAA" +
+    "bgEAAAMgAAACAAAAJwIAAAAgAAABAAAAMgIAAAAQAAABAAAAQAIAAA==");
+
+  public static void doTest(Transform2 t) {
+    t.sayHi("NewInterface");
+    try {
+      Main.doCommonClassRedefinition(Transform2.class, CLASS_BYTES, DEX_BYTES);
+    } catch (Exception e) {
+      System.out.println(
+          "Transformation error : " + e.getClass().getName() + "(" + e.getMessage() + ")");
+    }
+    t.sayHi("NewInterface");
+  }
+}
diff --git a/test/921-hello-failure/src/NewName.java b/test/921-hello-failure/src/NewName.java
new file mode 100644
index 0000000..a6f249a
--- /dev/null
+++ b/test/921-hello-failure/src/NewName.java
@@ -0,0 +1,56 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import java.util.Base64;
+
+class NewName {
+  // class NotTransform {
+  //   public void sayHi(String name) {
+  //     throw new Error("Should not be called!");
+  //   }
+  // }
+  private static final byte[] CLASS_BYTES = Base64.getDecoder().decode(
+    "yv66vgAAADQAFQoABgAPBwAQCAARCgACABIHABMHABQBAAY8aW5pdD4BAAMoKVYBAARDb2RlAQAP" +
+    "TGluZU51bWJlclRhYmxlAQAFc2F5SGkBABUoTGphdmEvbGFuZy9TdHJpbmc7KVYBAApTb3VyY2VG" +
+    "aWxlAQARTm90VHJhbnNmb3JtLmphdmEMAAcACAEAD2phdmEvbGFuZy9FcnJvcgEAFVNob3VsZCBu" +
+    "b3QgYmUgY2FsbGVkIQwABwAMAQAMTm90VHJhbnNmb3JtAQAQamF2YS9sYW5nL09iamVjdAAgAAUA" +
+    "BgAAAAAAAgAAAAcACAABAAkAAAAdAAEAAQAAAAUqtwABsQAAAAEACgAAAAYAAQAAAAEAAQALAAwA" +
+    "AQAJAAAAIgADAAIAAAAKuwACWRIDtwAEvwAAAAEACgAAAAYAAQAAAAMAAQANAAAAAgAO");
+  private static final byte[] DEX_BYTES = Base64.getDecoder().decode(
+    "ZGV4CjAzNQDLV95i5xnv6iUi6uIeDoY5jP5Xe9NP1AiYAgAAcAAAAHhWNBIAAAAAAAAAAAQCAAAL" +
+    "AAAAcAAAAAUAAACcAAAAAgAAALAAAAAAAAAAAAAAAAQAAADIAAAAAQAAAOgAAACQAQAACAEAAEoB" +
+    "AABSAQAAYgEAAHUBAACJAQAAnQEAALABAADHAQAAygEAAM4BAADiAQAAAQAAAAIAAAADAAAABAAA" +
+    "AAcAAAAHAAAABAAAAAAAAAAIAAAABAAAAEQBAAAAAAAAAAAAAAAAAQAKAAAAAQABAAAAAAACAAAA" +
+    "AAAAAAAAAAAAAAAAAgAAAAAAAAAFAAAAAAAAAPQBAAAAAAAAAQABAAEAAADpAQAABAAAAHAQAwAA" +
+    "AA4ABAACAAIAAADuAQAACQAAACIAAQAbAQYAAABwIAIAEAAnAAAAAQAAAAMABjxpbml0PgAOTE5v" +
+    "dFRyYW5zZm9ybTsAEUxqYXZhL2xhbmcvRXJyb3I7ABJMamF2YS9sYW5nL09iamVjdDsAEkxqYXZh" +
+    "L2xhbmcvU3RyaW5nOwARTm90VHJhbnNmb3JtLmphdmEAFVNob3VsZCBub3QgYmUgY2FsbGVkIQAB" +
+    "VgACVkwAEmVtaXR0ZXI6IGphY2stNC4yMAAFc2F5SGkAAQAHDgADAQAHDgAAAAEBAICABIgCAQGg" +
+    "AgAADAAAAAAAAAABAAAAAAAAAAEAAAALAAAAcAAAAAIAAAAFAAAAnAAAAAMAAAACAAAAsAAAAAUA" +
+    "AAAEAAAAyAAAAAYAAAABAAAA6AAAAAEgAAACAAAACAEAAAEQAAABAAAARAEAAAIgAAALAAAASgEA" +
+    "AAMgAAACAAAA6QEAAAAgAAABAAAA9AEAAAAQAAABAAAABAIAAA==");
+
+  public static void doTest(Transform t) {
+    t.sayHi("NewName");
+    try {
+      Main.doCommonClassRedefinition(Transform.class, CLASS_BYTES, DEX_BYTES);
+    } catch (Exception e) {
+      System.out.println(
+          "Transformation error : " + e.getClass().getName() + "(" + e.getMessage() + ")");
+    }
+    t.sayHi("NewName");
+  }
+}
diff --git a/test/921-hello-failure/src/ReorderInterface.java b/test/921-hello-failure/src/ReorderInterface.java
new file mode 100644
index 0000000..ce78dbc
--- /dev/null
+++ b/test/921-hello-failure/src/ReorderInterface.java
@@ -0,0 +1,59 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import java.util.Base64;
+
+class ReorderInterface {
+  // The following is a base64 encoding of the following class.
+  // class Transform2 implements Iface2, Iface1 {
+  //   public void sayHi(String name) {
+  //     throw new Error("Should not be called!");
+  //   }
+  // }
+  private static final byte[] CLASS_BYTES = Base64.getDecoder().decode(
+    "yv66vgAAADQAGQoABgARBwASCAATCgACABQHABUHABYHABcHABgBAAY8aW5pdD4BAAMoKVYBAARD" +
+    "b2RlAQAPTGluZU51bWJlclRhYmxlAQAFc2F5SGkBABUoTGphdmEvbGFuZy9TdHJpbmc7KVYBAApT" +
+    "b3VyY2VGaWxlAQAPVHJhbnNmb3JtMi5qYXZhDAAJAAoBAA9qYXZhL2xhbmcvRXJyb3IBABVTaG91" +
+    "bGQgbm90IGJlIGNhbGxlZCEMAAkADgEAClRyYW5zZm9ybTIBABBqYXZhL2xhbmcvT2JqZWN0AQAG" +
+    "SWZhY2UyAQAGSWZhY2UxACAABQAGAAIABwAIAAAAAgAAAAkACgABAAsAAAAdAAEAAQAAAAUqtwAB" +
+    "sQAAAAEADAAAAAYAAQAAAAEAAQANAA4AAQALAAAAIgADAAIAAAAKuwACWRIDtwAEvwAAAAEADAAA" +
+    "AAYAAQAAAAMAAQAPAAAAAgAQ");
+  private static final byte[] DEX_BYTES = Base64.getDecoder().decode(
+    "ZGV4CjAzNQChWfUC02YEHJZLC4V4pHrGMdqwD8NnzXvAAgAAcAAAAHhWNBIAAAAAAAAAACwCAAAN" +
+    "AAAAcAAAAAcAAACkAAAAAgAAAMAAAAAAAAAAAAAAAAQAAADYAAAAAQAAAPgAAACoAQAAGAEAAGIB" +
+    "AABqAQAAdAEAAH4BAACMAQAAnwEAALMBAADHAQAA3gEAAO8BAADyAQAA9gEAAAoCAAABAAAAAgAA" +
+    "AAMAAAAEAAAABQAAAAYAAAAJAAAACQAAAAYAAAAAAAAACgAAAAYAAABcAQAAAgAAAAAAAAACAAEA" +
+    "DAAAAAMAAQAAAAAABAAAAAAAAAACAAAAAAAAAAQAAABUAQAACAAAAAAAAAAcAgAAAAAAAAEAAQAB" +
+    "AAAAEQIAAAQAAABwEAMAAAAOAAQAAgACAAAAFgIAAAkAAAAiAAMAGwEHAAAAcCACABAAJwAAAAIA" +
+    "AAABAAAAAQAAAAUABjxpbml0PgAITElmYWNlMTsACExJZmFjZTI7AAxMVHJhbnNmb3JtMjsAEUxq" +
+    "YXZhL2xhbmcvRXJyb3I7ABJMamF2YS9sYW5nL09iamVjdDsAEkxqYXZhL2xhbmcvU3RyaW5nOwAV" +
+    "U2hvdWxkIG5vdCBiZSBjYWxsZWQhAA9UcmFuc2Zvcm0yLmphdmEAAVYAAlZMABJlbWl0dGVyOiBq" +
+    "YWNrLTQuMjAABXNheUhpAAEABw4AAwEABw4AAAABAQCAgASYAgEBsAIAAAwAAAAAAAAAAQAAAAAA" +
+    "AAABAAAADQAAAHAAAAACAAAABwAAAKQAAAADAAAAAgAAAMAAAAAFAAAABAAAANgAAAAGAAAAAQAA" +
+    "APgAAAABIAAAAgAAABgBAAABEAAAAgAAAFQBAAACIAAADQAAAGIBAAADIAAAAgAAABECAAAAIAAA" +
+    "AQAAABwCAAAAEAAAAQAAACwCAAA=");
+
+  public static void doTest(Transform2 t) {
+    t.sayHi("ReorderInterface");
+    try {
+      Main.doCommonClassRedefinition(Transform2.class, CLASS_BYTES, DEX_BYTES);
+    } catch (Exception e) {
+      System.out.println(
+          "Transformation error : " + e.getClass().getName() + "(" + e.getMessage() + ")");
+    }
+    t.sayHi("ReorderInterface");
+  }
+}
diff --git a/test/921-hello-failure/src/Transform.java b/test/921-hello-failure/src/Transform.java
new file mode 100644
index 0000000..ee444f0
--- /dev/null
+++ b/test/921-hello-failure/src/Transform.java
@@ -0,0 +1,21 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+class Transform {
+  public void sayHi(String name) {
+    System.out.println("hello - " + name);
+  }
+}
diff --git a/test/921-hello-failure/src/Transform2.java b/test/921-hello-failure/src/Transform2.java
new file mode 100644
index 0000000..9d949f3
--- /dev/null
+++ b/test/921-hello-failure/src/Transform2.java
@@ -0,0 +1,21 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+class Transform2 implements Iface1, Iface2 {
+  public void sayHi(String name) {
+    System.out.println("hello2 - " + name);
+  }
+}
diff --git a/test/ti-agent/common_helper.cc b/test/ti-agent/common_helper.cc
index ebf1e46..01b6c98 100644
--- a/test/ti-agent/common_helper.cc
+++ b/test/ti-agent/common_helper.cc
@@ -17,6 +17,7 @@
 #include "ti-agent/common_helper.h"
 
 #include <stdio.h>
+#include <sstream>
 
 #include "art_method.h"
 #include "jni.h"
@@ -41,8 +42,24 @@
 
 namespace common_redefine {
 
+static void throwRedefinitionError(jvmtiEnv* jvmti, JNIEnv* env, jclass target, jvmtiError res) {
+  std::stringstream err;
+  char* signature = nullptr;
+  char* generic = nullptr;
+  jvmti->GetClassSignature(target, &signature, &generic);
+  char* error = nullptr;
+  jvmti->GetErrorName(res, &error);
+  err << "Failed to redefine class <" << signature << "> due to " << error;
+  std::string message = err.str();
+  jvmti->Deallocate(reinterpret_cast<unsigned char*>(signature));
+  jvmti->Deallocate(reinterpret_cast<unsigned char*>(generic));
+  jvmti->Deallocate(reinterpret_cast<unsigned char*>(error));
+  env->ThrowNew(env->FindClass("java/lang/Exception"), message.c_str());
+}
+
 using RedefineDirectFunction = jvmtiError (*)(jvmtiEnv*, jclass, jint, const unsigned char*);
-static void DoClassTransformation(jvmtiEnv* jvmti_env, JNIEnv* env,
+static void DoClassTransformation(jvmtiEnv* jvmti_env,
+                                  JNIEnv* env,
                                   jclass target,
                                   jbyteArray class_file_bytes,
                                   jbyteArray dex_file_bytes) {
@@ -63,7 +80,7 @@
     res = f(jvmti_env, target, len, redef_bytes);
   }
   if (res != JVMTI_ERROR_NONE) {
-    printf("Redefinition failed!");
+    throwRedefinitionError(jvmti_env, env, target, res);
   }
 }
 
diff --git a/test/ti-agent/common_load.cc b/test/ti-agent/common_load.cc
index 2f4af9f..d7579ca 100644
--- a/test/ti-agent/common_load.cc
+++ b/test/ti-agent/common_load.cc
@@ -75,6 +75,7 @@
   { "918-fields", Test918Fields::OnLoad, nullptr },
   { "919-obsolete-fields", common_redefine::OnLoad, nullptr },
   { "920-objects", Test920Objects::OnLoad, nullptr },
+  { "921-hello-failure", common_redefine::OnLoad, nullptr },
 };
 
 static AgentLib* FindAgent(char* name) {