diff --git a/compiler/cpp/src/generate/t_java_generator.cc b/compiler/cpp/src/generate/t_java_generator.cc
index 0d2345a..a859894 100644
--- a/compiler/cpp/src/generate/t_java_generator.cc
+++ b/compiler/cpp/src/generate/t_java_generator.cc
@@ -1014,7 +1014,7 @@
     if ((*f_iter)->get_req() == t_field::T_REQUIRED) {
       if (bean_style_) {
         out <<
-          indent() << "if (" << generate_isset_check(*f_iter) << ") {" << endl <<
+          indent() << "if (!" << generate_isset_check(*f_iter) << ") {" << endl <<
           indent() << "  throw new TProtocolException(\"Required field '" << (*f_iter)->get_name() << "' is unset! Struct:\" + toString());" << endl <<
           indent() << "}" << endl << endl;
       } else{