What causes this retainAll exception?

Posted by Joren on Stack Overflow See other posts from Stack Overflow or by Joren
Published on 2010-05-20T00:57:08Z Indexed on 2010/05/20 1:00 UTC
Read the original article Hit count: 298

Filed under:

java

|

collections

|

google-datastore

java.lang.UnsupportedOperationException: This operation is not supported on Query Results
    at org.datanucleus.store.query.AbstractQueryResult.contains(AbstractQueryResult.java:250)
    at java.util.AbstractCollection.retainAll(AbstractCollection.java:369)
    at namespace.MyServlet.doGet(MyServlet.java:101)

I'm attempting to take one list I retrieved from a datastore query, and keep only the results which are also in a list I retrieved from a list of keys. Both my lists are populated as expected, but I can't seem to user retainAll on either one of them.

//                  List<Data> listOne = new ArrayList(query.execute(theQuery));
//                  DatastoreService ds = DatastoreServiceFactory.getDatastoreService();
//                  List<Data> listTwo = new ArrayList(ds.get(keys).values());
//                  listOne.retainAll(listTwo);

© Stack Overflow or respective owner

Related posts about java

Tomcat 6: Access Control Exception?

as seen on Server Fault - Search for 'Server Fault'
I'm trying to setup a tomcat6 server, and I'm trying to match another setup someone else established. However, my deployment (default Ubuntu install) uses a policy.d/ directory structure, and the established server just uses a catalina.policy file. I've tried setting every entry in policy.d to match… >>> More
Problem in creation MDB Queue connection at Jboss StartUp

as seen on Stack Overflow - Search for 'Stack Overflow'
I am not able to create a Queue connection in JBOSS4.2.3GA Version & Java1.5, as I am using MDB as per the below details. I am putting this MDB in a jar file(named utsJar.jar) and copied it in deploy folder of JBOSS, In the test env. this MDB works well but in another env. [ env settings and… >>> More
failing to establish connection between Postgres db and gwt

as seen on Stack Overflow - Search for 'Stack Overflow'
Hi, I am using Postgres and gwt 2.0 for one of my applications. I am facing problem connecting to the database. When I try to connect it gives "ClassNotFoundException". Here is what I get when I try to connect to database: java.lang.ClassNotFoundException: org.postgresql.Driver at java.net… >>> More
failing to establish connection between postgre db and gwt

as seen on Stack Overflow - Search for 'Stack Overflow'
Hi, For i am using postgre and gwt 2.0 for one of my applications. I am facing problem connecting to the database. When i try to connect it gives "ClassNotFoundException". Here is what i get when i try to connect to database: java.lang.ClassNotFoundException: org.postgresql.Driver at java.net… >>> More
Migration and deployement problems JBoss 4.2.2.GA to JBoss 6.0.0.M2

as seen on Stack Overflow - Search for 'Stack Overflow'
Hi, I'm trying to migrate an application running on JBoss 4.2.2.GA to JBoss 6.0.0.M2 I give you some log to explain my problem : boot.log : 2010-03-16 09:59:29,406 ERROR [org.jboss.system.server.profileservice.ProfileServiceBootstrap] (Thread-2) Failed to load profile: Summary of incomplete deployments… >>> More

Related posts about collections

Creating a custom collections class using System.Collections.CollectionBase

as seen on C# Corner - Search for 'C# Corner'
This article will show you how you can create a class that can behave just like a collection class. >>> More
C#/.NET Little Wonders: The Concurrent Collections (1 of 3)

as seen on Geeks with Blogs - Search for 'Geeks with Blogs'
Once again we consider some of the lesser known classes and keywords of C#. In the next few weeks, we will discuss the concurrent collections and how they have changed the face of concurrent programming. This week’s post will begin with a general introduction and discuss the ConcurrentStack<T>… >>> More
C#/.NET Fundamentals: Choosing the Right Collection Class

as seen on Geeks with Blogs - Search for 'Geeks with Blogs'
The .NET Base Class Library (BCL) has a wide array of collection classes at your disposal which make it easy to manage collections of objects. While it's great to have so many classes available, it can be daunting to choose the right collection to use for any given situation. As hard as it may be… >>> More
Using Tree(Map,Set) in Collections

as seen on Internet.com - Search for 'Internet.com'
To add objects to a Tree(Map, Set), implement the Comparable.compareTo method. >>> More
Using Tree(Map,Set) in Collections

as seen on Internet.com - Search for 'Internet.com'
To add objects to a Tree(Map, Set), implement the Comparable.compareTo method. >>> More