#vulnerable code 
                               @Override
   public Field<O> setLiteralInitializer(final String value)
   {
      String stub = "public class Stub { private String stub = " + value + " }";
      JavaClass temp = (JavaClass) JavaParser.parse(stub);
      FieldDeclaration internal = (FieldDeclaration) temp.getFields().get(0).getInternal();

      for (Object f : internal.fragments())
      {
         if (f instanceof VariableDeclarationFragment)
         {
            VariableDeclarationFragment tempFrag = (VariableDeclarationFragment) f;
            VariableDeclarationFragment localFrag = getFragment(field);
            localFrag.setInitializer((Expression) ASTNode.copySubtree(ast, tempFrag.getInitializer()));
            break;
         }
      }

      return this;
   } 
                            #location 14 
                            #vulnerability type NULL_DEREFERENCE
#fixed code
                               @Override
   public Field<O> setLiteralInitializer(final String value)
   {
      String stub = "public class Stub { private String stub = " + value + " }";
      JavaClass temp = (JavaClass) JavaParser.parse(stub);
      VariableDeclarationFragment tempFrag = (VariableDeclarationFragment) temp.getFields().get(0).getInternal();
      fragment.setInitializer((Expression) ASTNode.copySubtree(ast, tempFrag.getInitializer()));
      return this;
   }