code: protected void boxSensitive(final Type type) {
          if (type.getSize() == 2) {
              visitInsn(POP2);
          } else {
              visitInsn(POP);
          }
          visitLdcInsn("<sensitive " + type.getClassName() + ">");
      }
docs: Generate the instruction sequence needed to "box" a sensitive local variable
  as a <code>null</code> reference or the string
  &quot;&lt;sensitive <i>type</i>&gt;&quot;
  
  @param type
  the <code>Type</code> of the object in the specified local
  variable slot on the stack.