Browser spins when trying to expand tree structure in jasperServer web application

Issue Description: 

When attempting to schedule a report and navigating to the folder where the output file should be stored, the browser just spins forever when attempting to expand the tree structure showing the list of folders in the repository.

Resolution:

The following stack trace was generated around the time of the spinning behavior:

java.lang.NullPointerException

at java.lang.Class.forName0(Native Method)

at java.lang.Class.forName(Class.java:348)

at com.jaspersoft.jasperserver.api.common.service.impl.ObjectFactoryImpl.getImplementationClass(ObjectFactoryImpl.java:161)

at com.jaspersoft.jasperserver.api.common.service.impl.ImplementationClassObjectFactoryImpl.getImplementationClass(ImplementationClassObjectFactoryImpl.java:61)

at com.jaspersoft.jasperserver.search.filter.ResourceTypeSearchCriteriaFactory.create(ResourceTypeSearchCriteriaFactory.java:94)

at com.jaspersoft.jasperserver.api.metadata.common.service.impl.hibernate.HibernateRepositoryServiceImpl.getResources(HibernateRepositoryServiceImpl.java:2492)

at sun.reflect.GeneratedMethodAccessor640.invoke(Unknown Source)

at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)

at java.lang.reflect.Method.invoke(Method.java:498)

This indicates there may be some items in the repository that do not map to a set list of recognized repository resource types. The list of mappings can be found in the implementationClassMappings property of the mappingResourceFactory bean in WEB-INFapplicationContext.xml file. Upon closer examingation of the xml file, there were mappings that were incorrectly placed in the mappingResourceFactory bean instead of the persistentMappings bean.