NHibernate.MappingException: No persister for:

This can have at least the following reason:
You may forget du add for example HasMany for the persisting class to make a relationship.

 HasMany(x => x.myTableId).KeyColumn("mytableID");

No message body writer has been found for response class

No message body writer has been found for response class
You need to add the following in maven:



<dependency>
        <groupId>org.codehaus.jackson</groupId>
        <artifactId>jackson-jaxrs</artifactId>
        <version>1.3.0</version>
</dependency>



Error serializing the response, please check the server logs, response class

Add the following:

              <dependency>
<groupId>org.codehaus.jackson</groupId>
<artifactId>jackson-jaxrs</artifactId>
<version>1.9.9</version>
</dependency>
<dependency>
<groupId>org.codehaus.jackson</groupId>
<artifactId>jackson-xc</artifactId>
<version>1.9.9</version>
</dependency>

Unit test

 [TestMethod]
        public void can_save_and_read_pbentity2()
        {
            object id;

            // Save to database using PbPlatsannonsEntity
            using ( var tx = CurrentSession.BeginTransaction())
            {
                id =
                    CurrentSession.Save(
                        new PbPlatsannonsEntity
                            {   Annonsrubrik = "Rubrik annons",
                                AnnonstextXml = "XML annonstext",
                                AntalPlatser = 12
                               
                            });
                    tx.Commit();
            }
            CurrentSession.Clear();

            //Read from database
            using ( var tx = CurrentSession.BeginTransaction() )
            {
                var pbPlatsannonsEntity = CurrentSession.Get<PbPlatsannonsEntity>(id);
                Assert.Equals("Rubrik annons", pbPlatsannonsEntity.Annonsrubrik);
                Assert.Equals("XML annonstext", pbPlatsannonsEntity.AnnonstextXml);
                Assert.Equals(12, pbPlatsannonsEntity.AntalPlatser);
                //Assert.Equals(new DateTime(2000, 1, 1), pbPlatsannonsEntity.Created);
                tx.Commit();

            }

        }

Collections.sort java: sorting java object

//Sort aktlist
final Comparator< aktlist > DATE_ORDER =
                            new Comparator< aktlist >() {
@Override
public int compare( aktlist a1,  aktlist a2) {
   return a2.getDatum().compareTo(a1.getDatum());
}
};
Collections.sort( aktlist , DATE_ORDER);

More information:
http://docs.oracle.com/javase/tutorial/collections/interfaces/order.html

Error configuring application listener of class org.springframework.web.context.ContextLoaderListener

SEVERE: Error configuring application listener of class org.springframework.web.context.ContextLoaderListener


Se a solution in:
http://stackoverflow.com/questions/2595315/classnotfoundexception-when-running-a-spring-maven2-project-on-tomcat-6-from-w