THRIFT-3089 Assigning default ENUM values results in non-compilable java code if java namespace is not defined
Client: Java
Patch: Anna Dymek <aadymek@gmail.com>

This closes #490
diff --git a/compiler/cpp/src/generate/t_java_generator.cc b/compiler/cpp/src/generate/t_java_generator.cc
index 1b1963a..c45c798 100644
--- a/compiler/cpp/src/generate/t_java_generator.cc
+++ b/compiler/cpp/src/generate/t_java_generator.cc
@@ -700,8 +700,11 @@
       throw "compiler error: no const of base type " + t_base_type::t_base_name(tbase);
     }
   } else if (type->is_enum()) {
-    render << type->get_program()->get_namespace("java") << "."
-           << value->get_identifier_with_parent();
+    std::string namespace_prefix = type->get_program()->get_namespace("java");
+    if (namespace_prefix.length() > 0) {
+        namespace_prefix += ".";
+    }
+    render << namespace_prefix << value->get_identifier_with_parent();
   } else {
     string t = tmp("tmp");
     print_const_value(out, t, type, value, true);