7081804: Remove cause field from javax.xml.crypto.NoSuchMechnismException

[Sebastian Sickelmann]

Am 07.09.2011 19:51, schrieb Sean Mullan:
> On 9/3/11 1:04 PM, Sebastian Sickelmann wrote:
>> Am 02.09.2011 21:58, schrieb Sean Mullan:
>>> On 9/2/11 1:43 AM, Sebastian Sickelmann wrote:
>>>>>> Here is the updated webrev:
>>>>>> http://oss-patches.24.eu/openjdk8/NoSuchMechanismException/7011804_0/
>>>>> Hmm, the main problem I have with this change is that the printStackTrace
>>>>> methods will no longer print the stack trace of the cause because it will always
>>>>> be null. That doesn't seem right to me, as it could be considered an
>>>>> incompatible change, and it will make it harder to debug issues.
>>>> The printStackTrace in Throwable calls the overridden getCause().
>>>> Maybe we should add @Override to it.
>>>> Updated the webrev to:
>>>> http://oss-patches.24.eu/openjdk8/NoSuchMechanismException/7011804_1/
>>> In that case, my main concern is addressed then. I would probably want someone
>>> from our TCK team to also review it with respect to JSR 105 compatibility, so
>>> I'll see if I can find someone.
>> Fine, that would be good.
>>> But first, can you expand your webrev to include the other Exception classes in
>>> javax.xml.crypto.**?
>> The new webrev is here:
>> http://oss-patches.24.eu/openjdk8/NoSuchMechanismException/7011804_2/
> In some classes the initCause comment is misspelled as initCaus. What about a
> test case, for example testing to make sure initCause throws an exception? Can
> you write one?
While creating an test(suggested code below) for this, i thought a 
little bit about if it is really good to change the behavoir of the 
ctors without a cause (defaultctor, ctor with message).
What is the best behavoir (see DEFAULT and MESSAGE_ONLY cases below) . 
Should in the cases DEFAULT and MESSAGE_ONLY the cause mutable? I 
actually think this would the better solution, cause it is what the 
users can actually do with the exceptions in javax/xml/crypto. Or should 
the test check on imutability in all cases?

> Also, I have asked someone from the TCK team to look at this and he said he will
> do that by Friday. It might require a CCC change because the behavior of
> initCause is different. I am hoping it doesn't require a JSR 105 maintenance
> revision though.
>
> --Sean





public class PreventOverridingOfChaining {

     private static final Class[] DEFAULT = new Class[]{};
     private static final Class[] MESSAGE_ONLY = new Class[]{String.class};
     private static final Class[] CAUSE_ONLY = new Class[]{Throwable.class};
     private static final Class[] BOTH = new Class[]{String.class, 
Throwable.class};
     private static final Class[] URI_REFERENCE_SPECIAL = new 
Class[]{String.class, Throwable.class, URIReference.class};

     public static void main(String args[]) throws Exception {
         check(NoSuchMechanismException.class);
         // all other exceptions.
     }

     private static void check(Class<? extends Throwable> exClass) 
throws ReflectiveOperationException {
         Constructor<? extends Throwable>[] constructors = 
(Constructor<? extends Throwable>[]) exClass.getConstructors();
         for (Constructor<? extends Throwable> ctor : constructors) {
             Class[] parameterTypes = ctor.getParameterTypes();
             if (Arrays.equals(DEFAULT, parameterTypes)) {
                 checkMutable(ctor.newInstance());
             } else if (Arrays.equals(MESSAGE_ONLY, parameterTypes)) {
                 checkMutable(ctor.newInstance("msg"));
             } else if (Arrays.equals(CAUSE_ONLY, parameterTypes)) {
                 checkImutable(ctor.newInstance(new 
RuntimeException("RE")));
             } else if (Arrays.equals(BOTH, parameterTypes)) {
                 checkImutable(ctor.newInstance("msg",new 
RuntimeException("RE")));
             } else if (Arrays.equals(URI_REFERENCE_SPECIAL, 
parameterTypes)) {
                 checkImutable(ctor.newInstance("msg",new 
RuntimeException("RE"),new URIReference() {

                     @Override
                     public String getURI() {
                         return "URI";
                     }

                     @Override
                     public String getType() {
                         return "Type";
                     }
                 }));
             }
         }
     }

     private static void checkMutable(Throwable th) {
         th.initCause(new RuntimeException());
     }

     private static void checkImutable(Throwable th) {
         try {
             th.initCause(new RuntimeException());
             throw new RuntimeException("Exception expected");
         } catch (IllegalStateException e) {
             // Everything is fine
         }
     }
}