diff --git a/src/main/java/soot/dexpler/DexFileProvider.java b/src/main/java/soot/dexpler/DexFileProvider.java
index 190a99ea58b..9e04924f6b9 100644
--- a/src/main/java/soot/dexpler/DexFileProvider.java
+++ b/src/main/java/soot/dexpler/DexFileProvider.java
@@ -230,6 +230,10 @@ private Map<String, DexContainer<? extends DexFile>> mappingForFile(File dexSour
     while (entryNameIterator.hasPrevious()) {
       String entryName = entryNameIterator.previous();
       DexEntry<? extends DexFile> entry = dexContainer.getEntry(entryName);
+      if (!acceptFile(entry)) {
+        continue;
+      }
+
       entryName = deriveDexName(entryName);
       logger.debug("" + String.format("Found dex file '%s' with %d classes in '%s'", entryName,
           entry.getDexFile().getClasses().size(), dexSourceFile.getCanonicalPath()));
@@ -249,6 +253,10 @@ private Map<String, DexContainer<? extends DexFile>> mappingForFile(File dexSour
     return Collections.unmodifiableMap(dexMap);
   }
 
+  protected boolean acceptFile(DexEntry<? extends DexFile> entry) {
+    return true;
+  }
+
   private String deriveDexName(String entryName) {
     return new File(entryName).getName();
   }
diff --git a/src/main/java/soot/toDex/ExprVisitor.java b/src/main/java/soot/toDex/ExprVisitor.java
index fade954d23b..2960b7b70ff 100644
--- a/src/main/java/soot/toDex/ExprVisitor.java
+++ b/src/main/java/soot/toDex/ExprVisitor.java
@@ -702,7 +702,7 @@ protected void castObject(Register sourceReg, Type castType) {
     }
   }
 
-  private void castPrimitive(Register sourceReg, Value source, Type castSootType) {
+  protected void castPrimitive(Register sourceReg, Value source, Type castSootType) {
     PrimitiveType castType = PrimitiveType.getByName(castSootType.toString());
 
     // Fix null_types on the fly. This should not be necessary, but better