Review

finding-16

org/apache/commons/bcel6/verifier/structurals/InstConstraintVisitor.java

visitATHROW(ATHROW)

class InstConstraintVisitor {
    /**
     * Ensures the specific preconditions of the said instruction.
     */
    @Override
    public void visitATHROW(ATHROW o){
        try {
        // It's stated that 'objectref' must be of a ReferenceType --- but since Throwable is
        // not derived from an ArrayType, it follows that 'objectref' must be of an ObjectType or Type.NULL.
        if (! ((stack().peek() instanceof ObjectType) || (stack().peek().equals(Type.NULL))) ){
            constraintViolated(o, "The 'objectref' is not of an (initialized) ObjectType but of type "+stack().peek()+".");
        }

        // NULL is a subclass of every class, so to speak.
        if (stack().peek().equals(Type.NULL)) {
            return;
        }

        ObjectType exc = (ObjectType) (stack().peek());
        ObjectType throwable = (ObjectType) (Type.getType("Ljava/lang/Throwable;"));
        if ( (! (exc.subclassOf(throwable)) ) && (! (exc.equals(throwable))) ){
            constraintViolated(o,
                "The 'objectref' is not of class Throwable or of a subclass of Throwable, but of '"+stack().peek()+"'.");
        }
        } catch (ClassNotFoundException e) {
        // FIXME: maybe not the best way to handle this
        throw new AssertionViolatedException("Missing class: " + e, e);
        }
    }

}