Executable model compiler casting int to short causes compilation error when variable is inside the bracket

rule "test_rule"
	dialect "java"
	when
		$integerToShort : IntegerToShort( $testInt : testInt		, testBoolean!=null, testBoolean==false) 
then
	System.out.println("rule_a fired ");
	$integerToShort.setTestShort((short)($testInt)); 
	$integerToShort.setTestBoolean(true);
	update($integerToShort);
end

 public static class IntegerToShort {

        private Boolean testBoolean;
        private int testInt;
        private Short testShort;
}