1 2 /** 3 * Create some objects and store them into an instance field. 4 */ 5 public class Main { 6 /** 7 * Entry point. 8 */ 9 public static void main(String[] args) { 10 Holder holder = new Holder(); 11 12 Blah blah = new Blah(); 13 14 /* strictly speaking, this should fail */ 15 holder.mValue = blah; 16 17 System.out.println("Assignment was allowed"); 18 19 /* try to use the reference; should fail */ 20 try { 21 holder.mValue.run(); 22 System.err.println("ERROR: did not get expected ICCE"); 23 } catch (IncompatibleClassChangeError icce) { 24 System.out.println("Got expected IncompatibleClassChangeError"); 25 } 26 27 /* for fun, verify that it's the "alternate" type */ 28 //Comparable cmpx = holder.mValue; /* compiler rejects */ 29 Comparable cmp = (Comparable) holder.mValue; 30 cmp.compareTo(cmp); 31 32 System.out.println("Done"); 33 } 34 } 35
