2016-01-04 2:22 GMT+03:00 Christopher Schultz <ch...@christopherschultz.net>:
> Konstantin,
>
> On 12/31/15 12:56 PM, Konstantin Kolinko wrote:
>> 2015-12-31 12:41 GMT+03:00 Tomasz Macnar <tomasz.mac...@comarch.pl>:
>>> Thanks for answer.
>>> I understand that application deploy order is the key to get context to
>>> deployed applicaitons (when application isn't deployed i can't get it
>>> context - it is clear).
>>> But ROOT application is deployed before app1, but i can't get ROOT context
>>> from app1.
>>> Is it in tomcat 8 possible to get ROOT context from other
>>> application (in servlet) ? If yes, coud tou give me an simple example ?
>>>
>>> In tomcat 6 when i put this configuration to server.xml
>>>
>>> <Context path="" docBase="${catalina.base}/webapps/ROOT" crossContext="true"
>>> />
>>>
>>> i have returned ROOT application context. The same code work fine in tomcat
>>> 6.
>>>
>>
>> Deployment order does not matter. What matters is whether other
>> context has already been started (registered in Mapper and is
>> available to serve requests). As you have already noted during your
>> debugging, "children" field in ContainerBase is a HashMap and the
>> entries are not ordered.
>>
>> Note that
>> 1) modern JRE uses random seed when evaluating String hash code to
>> mitigate hash collision attacks, so the order will be different on
>> different runs
>
> [citation needed]
>
> Oracle's Java 8 does not do this, nor do I suspect any other JREs out
> there, otherwise Serialization of things like HashMap would break all
> over the place.
>
> One could argue that modern JREs *should* do this, but backward
> compatibility is an impediment.Apparently this one: http://hg.openjdk.java.net/jdk9/dev/jdk/rev/43bd5ee0205e May 2012, so 3,5 years ago. Times flies fast.. String.java in JDK 7u80 has that code (HASHING_SEED field, hash32() method etc.). Implementation of String.hashCode() is immutable, because its algorithm is documented in official Javadoc for the method, but they went with a package-visible method "hash32()". The hg commit creates "hash32()" as a public method. It is package-visible in actual 7u80. There is no such method in 8u66, but the structure of a hashmap has evolved. There is no guarantee of an iteration order. Implementation of hashCode() does not matter for serialization, because HashMap serializes only the values (the key-value pairs), not the internal structure. Best regards, Konstantin Kolinko --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
