org.terrier.structures.indexing
Class MetaIndexBuilder

java.lang.Object
  org.terrier.structures.indexing.MetaIndexBuilder

All Implemented Interfaces:

Closeable

Direct Known Subclasses:

CompressingMetaIndexBuilder

public abstract class MetaIndexBuilder
extends Object
implements Closeable

Abstract class for writing document metadata. Metadata means textual data associated with a document, e.g. an external document identifier (e.g. docnos), a URL, or the title or abstracts of a document.

Lookups in the resulting <MetaIndex are supported in two manners - either by docid, or for specified key types, by value. In the latter scenario, metadata values are assumed to be unique.

Typical usage during indexing:

 MetaIndexBuilder metaBuilder = ...
 while(collection.nextDocument())
 {
        Document d = collection.getDocument();
  metaBuilder.writeDocumentEntry(d.getAllProperties());
 }
 

Since:

3.0

Author:

Craig Macdonald

Constructor Summary

MetaIndexBuilder()

Method Summary

abstract void	writeDocumentEntry(Map<String,String> data) Write out metadata for current document, extracted from specified map Typically, the MetaIndexBuilder will know which keys from data that it is interested in.
abstract void	writeDocumentEntry(String[] data) Write out metadata for current document.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface java.io.Closeable

close

Constructor Detail

MetaIndexBuilder

public MetaIndexBuilder()

Method Detail

writeDocumentEntry

public abstract void writeDocumentEntry(Map<String,String> data)
                                 throws IOException

Write out metadata for current document, extracted from specified map Typically, the MetaIndexBuilder will know which keys from data that it is interested in.

Throws:

IOException

writeDocumentEntry

public abstract void writeDocumentEntry(String[] data)
                                 throws IOException

Write out metadata for current document. Values for all keys are specified.

Throws:

IOException