Instances of this class are thrown by BCEL's class file verifier "JustIce" when a class file to verify does not pass the verification pass 3 because of a violation of a static constraint as described in the Java Virtual Machine Specification, Second edition, 4.8.1, pages 133-137. The static constraints checking part of pass 3 is called pass 3a in JustIce. Static constraints on the instructions in the code array are checked early in pass 3a and are described on page 134 in the Java Virtual Machine Specification, Second Edition.