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public class: OrdFieldSource [javadoc | source]

All Implemented Interfaces:

Expert: obtains the ordinal of the field value from the default Lucene Fieldcache using getStringIndex().

The native lucene index order is used to assign an ordinal value for each field value.

If there were only three field values: "apple","banana","pear"
then ord("apple")=1, ord("banana")=2, ord("pear")=3

WARNING: ord() depends on the position in an index and can thus change when other documents are inserted or deleted, or if a MultiSearcher is used.

WARNING: The status of the search.function package is experimental. The APIs introduced here might change in the future and will not be supported anymore in such a case.

NOTE: with the switch in 2.9 to segment-based searching, if #getValues is invoked with a composite (multi-segment) reader, this can easily cause double RAM usage for the values in the FieldCache. It's best to switch your application to pass only atomic (single segment) readers to this API.

Field Summary
protected  String field     
 public OrdFieldSource(String field) 
    Constructor for a certain field.
    field - field whose values order is used.
Method from org.apache.lucene.search.function.OrdFieldSource Summary:
description,   equals,   getValues,   hashCode
Methods from org.apache.lucene.search.function.ValueSource:
description,   equals,   getValues,   hashCode,   toString
Methods from java.lang.Object:
clone,   equals,   finalize,   getClass,   hashCode,   notify,   notifyAll,   toString,   wait,   wait,   wait
Method from org.apache.lucene.search.function.OrdFieldSource Detail:
 public String description() 
 public boolean equals(Object o) 
 public DocValues getValues(IndexReader reader) throws IOException 
 public int hashCode()