This project contains the implementation of an idea how to improve SolrMarc by improving performance, extendability and stability.

The indexer is divided in a compile time and a runtime. The compile time is for loading configurations and translate/compile them to small indexer tasks with minimal functionality. The runtime loads records from input files, uses the small indexer tasks to extract data and send the data to Solr.

This is mainly made out of factories. Each Factory is for one type of import configuration of the indexer properties (e.g marc.properties or marc_local.properties). Such a factory parses the configuration and creates a small indexer task. A factory is not a singleton but only one instance of this factory will be used, so each factory can build a cache or share information between indexer tasks. After the all configurations are compiled to tasks the factories will not be needed anymore and will be collected by the Garbage Collector. A task is not allowed to own an instance of its factory. Every single bit of calculation which can be done by the factory is a good bit of calculation. Everything which can be preprocessed should be done by the factory, not by the indexer task.

At this point only the indexer task exists. No factories, no properties, no unnecessary processing. The input file gets read and for each record all indexer tasks will be called to create a new document.

A task is represented by the AbstractValueIndexer class and is a composition of three parts.

• Extractor: reads data from a record
• Mapping: translates the data by e.g mapping one value to another or by using a regex to extract a value.
• Collector: transforms the data by e.g joining multiple strings to one string or by splitting a string in parts.

Each indexer task will generate the data of one solr field.