anchor.diff:  class Con { String s = "\nHello World\n"; }
   ^Z
   
  -C:\Users\peter>javac A.java // (1)
  +C:\Users\peter>javac A.java # <1>
   ╩■║╛   4 
              s Ljava/lang/String; <init> ()V Code LineNumberTable
   SourceFile A.java
positive.code:    System.out.println("Assertions are on");
  ----
  
  This shows you can easily determine is assertions are on for expensive checks. Another simple approach is
  
  [source, Java]
  ----
  
negative.code:         ints.remove(i); 
  ----
  
  Wrapper pooling covers the range -128 to 127 for `Byte`, `Short`, `Character`, `Integer` and `Long`. (Possibly higher for `Integer` depending on command line options.)
  
  [source, Java]
  ----
  