diff --git a/java/core/src/main/java/com/google/protobuf/AbstractMessage.java b/java/core/src/main/java/com/google/protobuf/AbstractMessage.java
index f383625b255e..30eccc1eca96 100644
--- a/java/core/src/main/java/com/google/protobuf/AbstractMessage.java
+++ b/java/core/src/main/java/com/google/protobuf/AbstractMessage.java
@@ -538,44 +538,4 @@ public BuilderType mergeFrom(
       return (BuilderType) super.mergeFrom(input, extensionRegistry);
     }
   }
-
-  /**
-   * @deprecated from v3.0.0-beta-3+, for compatibility with v2.5.0 and v2.6.1
-   * generated code.
-   */
-  @Deprecated
-  protected static int hashLong(long n) {
-    return (int) (n ^ (n >>> 32));
-  }
-
-  /**
-   * @deprecated from v3.0.0-beta-3+, for compatibility with v2.5.0 and v2.6.1
-   * generated code.
-   */
-  @Deprecated
-  protected static int hashBoolean(boolean b) {
-    return b ? 1231 : 1237;
-  }
-
-  /**
-   * @deprecated from v3.0.0-beta-3+, for compatibility with v2.5.0 and v2.6.1
-   * generated code.
-   */
-  @Deprecated
-  protected static int hashEnum(EnumLite e) {
-    return e.getNumber();
-  }
-
-  /**
-   * @deprecated from v3.0.0-beta-3+, for compatibility with v2.5.0 and v2.6.1
-   * generated code.
-   */
-  @Deprecated
-  protected static int hashEnumList(List<? extends EnumLite> list) {
-    int hash = 1;
-    for (EnumLite e : list) {
-      hash = 31 * hash + hashEnum(e);
-    }
-    return hash;
-  }
 }
diff --git a/java/core/src/main/java/com/google/protobuf/GeneratedMessageLite.java b/java/core/src/main/java/com/google/protobuf/GeneratedMessageLite.java
index c153960de91b..115f4288cd61 100644
--- a/java/core/src/main/java/com/google/protobuf/GeneratedMessageLite.java
+++ b/java/core/src/main/java/com/google/protobuf/GeneratedMessageLite.java
@@ -1440,7 +1440,7 @@ protected Object readResolve() throws ObjectStreamException {
       } catch (ClassNotFoundException e) {
         throw new RuntimeException("Unable to find proto buffer class: " + messageClassName, e);
       } catch (NoSuchFieldException e) {
-        return readResolveFallback();
+        throw new RuntimeException("Unable to find DEFAULT_INSTANCE in " + messageClassName, e);
       } catch (SecurityException e) {
         throw new RuntimeException("Unable to call DEFAULT_INSTANCE in " + messageClassName, e);
       } catch (IllegalAccessException e) {
@@ -1450,33 +1450,6 @@ protected Object readResolve() throws ObjectStreamException {
       }
     }
 
-    /**
-     * @deprecated from v3.0.0-beta-3+, for compatibility with v2.5.0 and v2.6.1 generated code.
-     */
-    @Deprecated
-    private Object readResolveFallback() throws ObjectStreamException {
-      try {
-        Class<?> messageClass = resolveMessageClass();
-        java.lang.reflect.Field defaultInstanceField =
-            messageClass.getDeclaredField("defaultInstance");
-        defaultInstanceField.setAccessible(true);
-        MessageLite defaultInstance = (MessageLite) defaultInstanceField.get(null);
-        return defaultInstance.newBuilderForType()
-            .mergeFrom(asBytes)
-            .buildPartial();
-      } catch (ClassNotFoundException e) {
-        throw new RuntimeException("Unable to find proto buffer class: " + messageClassName, e);
-      } catch (NoSuchFieldException e) {
-        throw new RuntimeException("Unable to find defaultInstance in " + messageClassName, e);
-      } catch (SecurityException e) {
-        throw new RuntimeException("Unable to call defaultInstance in " + messageClassName, e);
-      } catch (IllegalAccessException e) {
-        throw new RuntimeException("Unable to call parsePartialFrom", e);
-      } catch (InvalidProtocolBufferException e) {
-        throw new RuntimeException("Unable to understand proto buffer", e);
-      }
-    }
-
     private Class<?> resolveMessageClass() throws ClassNotFoundException {
       return messageClass != null ? messageClass : Class.forName(messageClassName);
     }