src/jdk.compiler/share/classes/com/sun/tools/javac/comp/Check.java

*** 3564,3573 ****
--- 3564,3587 ----
              log.warning(pos,
                          Warnings.AuxiliaryClassAccessedFromOutsideOfItsSourceFile(c, c.sourcefile));
          }
      }
  
+     /**
+      * 
+      */
+     void checkDefaultConstructor(ClassSymbol c) {
+         // Kick out anonymous and private?
+         if (lint.isEnabled(Lint.LintCategory.DEFAULT_CTOR) &&
+             (c.flags() & ENUM) == 0 &&
+             !c.isAnonymous() &&
+             (c.flags() & PUBLIC) != 0) {
+             System.out.println("Default ctor on " + c);
+         }
+         return;
+     }
+ 
      private class ConversionWarner extends Warner {
          final String uncheckedKey;
          final Type found;
          final Type expected;
          public ConversionWarner(DiagnosticPosition pos, String uncheckedKey, Type found, Type expected) {