diff --git a/src/main/java/org/bytedeco/javacpp/tools/Generator.java b/src/main/java/org/bytedeco/javacpp/tools/Generator.java
index 903dbf151..a20c471f0 100644
--- a/src/main/java/org/bytedeco/javacpp/tools/Generator.java
+++ b/src/main/java/org/bytedeco/javacpp/tools/Generator.java
@@ -1388,6 +1388,7 @@ boolean classes(boolean handleExceptions, boolean defineAdapters, boolean conver
             out.println("    UniquePtrAdapter(      U& uniquePtr) : ptr(0), size(0), owner(0), uniquePtr2(U(NULL, D())), uniquePtr(uniquePtr) { }");
             out.println("    UniquePtrAdapter(const U* uniquePtr) : ptr(0), size(0), owner(0), uniquePtr2(U(NULL, D())), uniquePtr(*(U*)uniquePtr) { }");
             out.println("    void assign(T* ptr, size_t size, void* owner) {");
+            out.println("        if (this->ptr == ptr && this->size == size && this->owner == owner) return;");
             out.println("        this->ptr = ptr;");
             out.println("        this->size = size;");
             out.println("        this->owner = owner;");
@@ -3245,7 +3246,11 @@ void callback(Class<?> cls, Method callbackMethod, String callbackName, int allo
 
                     if (adapterInfo != null) {
                         usesAdapters = true;
-                        out.println("    " + adapterInfo.name + " adapter" + j + "(arg" + j + ");");
+                        String cast2 = adapterInfo.cast2.trim();
+                        if (cast2.length() > 0 && !cast2.startsWith("(") && !cast2.endsWith(")")) {
+                            cast2 = "(" + cast2 + ")";
+                        }
+                        out.println("    " + adapterInfo.name + " adapter" + j + "(" + cast2 + "arg" + j + ");");
                     }
 
                     if (Pointer.class.isAssignableFrom(callbackParameterTypes[j]) ||
diff --git a/src/test/java/org/bytedeco/javacpp/AdapterTest.java b/src/test/java/org/bytedeco/javacpp/AdapterTest.java
index 51807fa98..31f82e8f4 100644
--- a/src/test/java/org/bytedeco/javacpp/AdapterTest.java
+++ b/src/test/java/org/bytedeco/javacpp/AdapterTest.java
@@ -271,16 +271,19 @@ static class UniqueFunction extends FunctionPointer {
         sharedData = fetchSharedData();
         assertEquals(13, sharedData.data());
 
+        final SharedData[] sharedData2 = new SharedData[1];
         int data = testCallback(new SharedFunction() {
             @Override public int call(SharedData d) {
-                int data = d.data();
-                d.deallocate();
-                return 2 * data;
+                d.data(2 * d.data());
+                sharedData2[0] = d;
+                return 3 * d.data();
             }
         }, sharedData);
-        assertEquals(2 * 13, data);
+        assertEquals(2 * 13, sharedData2[0].data());
+        assertEquals(2 * 3 * 13, data);
 
         sharedData.deallocate();
+        sharedData2[0].deallocate();
 
         assertEquals(1, constructorCount());
         assertEquals(1, destructorCount());
@@ -310,14 +313,17 @@ static class UniqueFunction extends FunctionPointer {
         uniqueData = fetchUniqueData();
         assertEquals(42, uniqueData.data());
 
+        final UniqueData[] uniqueData2 = new UniqueData[1];
         int data = testCallback(new UniqueFunction() {
             @Override public int call(UniqueData d) {
-                int data = d.data();
-                d.deallocate();
-                return 2 * data;
+                d.data(2 * d.data());
+                uniqueData2[0] = d;
+                return 3 * d.data();
             }
         }, uniqueData);
-        assertEquals(2 * 42, data);
+        assertEquals(2 * 42, uniqueData2[0].data());
+        assertEquals(2 * 3 * 42, data);
+        uniqueData2[0].deallocate();
         System.gc();
     }