fix #394 needs to be fully qualified and not abstract

annotations/builder/src/main/java/io/sundr/builder/internal/functions/ClazzAs.java

@@ -619,8 +619,9 @@ private static List<Statement> toInstanceConstructorBody(RichTypeDef clazz, Type
       statements.add(new StringStatement("this.fluent = " + fluent + "; "));
     }
 
-    if (hasDefaultConstructor(clazz)) {
-      statements.add(new StringStatement("instance = (instance != null ? instance : new " + clazz.getName() + "());\n"));
+    if (!isAbstract(clazz.toReference()) && hasDefaultConstructor(clazz)) {
+      statements.add(
+          new StringStatement("instance = (instance != null ? instance : new " + clazz.getFullyQualifiedName() + "());\n"));
     }
 
     StringBuilder builder = new StringBuilder("if (instance != null) {\n");

tests/buildable-fields/src/main/java/io/sundr/tests/AbstractWithDefaults.java

@@ -0,0 +1,38 @@
+/**
+ * Copyright 2015 The original authors.
+ *
+ * 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.
+ *
+**/
+
+package io.sundr.tests;
+
+import io.sundr.builder.annotations.Buildable;
+
+/**
+ * A simple Pojo that demonstrates default fields are preserved
+ */
+@Buildable
+public abstract class AbstractWithDefaults {
+
+  private String field = "Hello";
+
+  public String getField() {
+    return field;
+  }
+
+  public void setField(String field) {
+    this.field = field;
+  }
+
+}

tests/buildable-fields/src/main/java/io/sundr/tests/WithDefaults.java

@@ -23,16 +23,6 @@
  * A simple Pojo that demonstrates default fields are preserved
  */
 @Buildable
-public class WithDefaults {
-
-  private String field = "Hello";
-
-  public String getField() {
-    return field;
-  }
-
-  public void setField(String field) {
-    this.field = field;
-  }
+public class WithDefaults extends AbstractWithDefaults {
 
 }