The larger your IT landscapes, the more difficult it can be for its users to find what they need, even with the best navigation mechanisms. A search engine should be capable of integrating with multiple systems of this kind. In the last chapter, we have seen the different data integration patterns that are possible with Apache Solr. Apache Solr is capable of reading data from different data sources. The next level of enterprise search demands deeper integration with Apache Solr. For example, a search user interface in the application uses Apache Solr or the applications run Apache Solr in an embedded mode. These are just different possibilities to explore while moving into a deeper integration. Many organizations would like to retain the user interface and usability of their existing application, while moving the underlying processing layer on Apache Solr.

Apache Solr has an active development community, which means heavy usage of Solr based across different...