Apache Solr Reference Guide Covering Apache Solr 6.0

Analyzers
An analyzer examines the text of fields and generates a token stream. Analyzers are specified as a child of the <
fieldType> element in the schema.xml configuration file (in the same conf/ directory as solrconfig.xml)
.
In normal usage, only fields of type solr.TextField will specify an analyzer. The simplest way to configure an
analyzer is with a single element whose class attribute is a fully qualified Java class name. The
named class must derive from org.apache.lucene.analysis.Analyzer. For example:
In this case a single class, WhitespaceAnalyzer, is responsible for analyzing the content of the named text
field and emitting the corresponding tokens. For simple cases, such as plain English prose, a single analyzer
class like this may be sufficient. But it's often necessary to do more complex analysis of the field content.
Even the most complex analysis requirements can usually be decomposed into a series of discrete, relatively
simple processing steps. As you will soon discover, the Solr distribution comes with a large selection of
tokenizers and filters that covers most scenarios you are likely to encounter. Setting up an analyzer chain is very
straightforward; you specify a simple element (no class attribute) with child elements that name
factory classes for the tokenizer and filters to use, in the order you want them to run.
For example:
Note that classes in the org.apache.solr.analysis package may be referred to here with the shorthand so
lr. prefix.
In this case, no Analyzer class was specified on the element. Rather, a sequence of more
specialized classes are wired together and collectively act as the Analyzer for the field. The text of the field is
passed to the first item in the list ( solr.StandardTokenizerFactory), and the tokens that emerge from the
last one ( solr.EnglishPorterFilterFactory) are the terms that are used for indexing or querying any
fields that use the "nametext" fieldType.
Field Values versus Indexed Terms
The output of an Analyzer affects the terms indexed in a given field (and the terms used when parsing
queries against those fields) but it has no impact on the stored value for the fields. For example: an
analyzer might split "Brown Cow" into two indexed terms "brown" and "cow", but the stored value will still
be a single String: "Brown Cow"
Apache Solr Reference Guide 6.0
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