Apache Solr Search Server: Test Framework
Packages 
Package Description
org.apache.solr
Common base classes for implementing tests.
org.apache.solr.analysis
Factories for Mock analysis classes that can be used in test configurations.
org.apache.solr.cloud
Base classes and utilities for creating and testing Solr Cloud clusters.
org.apache.solr.cloud.api.collections
Test framework classes for collection APIs
org.apache.solr.core
Factories for Mock classes that can be used in test configurations
org.apache.solr.handler
Concrete implementations of org.apache.solr.request.SolrRequestHandler
org.apache.solr.handler.component
Class for tracking shard requests
org.apache.solr.schema  
org.apache.solr.search
Mock classes for testing search.
org.apache.solr.search.facet  
org.apache.solr.search.function  
org.apache.solr.search.similarities  
org.apache.solr.spelling
Mock classes for testing spelling.
org.apache.solr.update.processor
Mock classes for testing Update Processor chains.
org.apache.solr.util
Misc utilities useful when implementing test cases.