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The configuration for the indexers is in the index-writers.xml file, included in the official Nutch distribution. The structure of this file is quite simple and consists mainly of a list of indexers (<writer> element):
<writers>
<writer id="<writer_id>" class="<implementation_class>">
<mapping>
...
</mapping>
<parameters>
...
</parameters>
</writer>
...
</writers>
Each <writer> element has two mandatory attributes:
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