Package org.apache.lucene.analysis

Class AnalyzerWrapper

java.lang.Object
org.apache.lucene.analysis.Analyzer
org.apache.lucene.analysis.AnalyzerWrapper
All Implemented Interfaces:
Closeable, AutoCloseable
Direct Known Subclasses:
LimitTokenCountAnalyzer, PerFieldAnalyzerWrapper, QueryAutoStopWordAnalyzer, ShingleAnalyzerWrapper
public abstract class AnalyzerWrapper extends Analyzer
Extension to Analyzer suitable for Analyzers which wrap other Analyzers.

getWrappedAnalyzer(String) allows the Analyzer to wrap multiple Analyzers which are selected on a per field basis.

wrapComponents(String, Analyzer.TokenStreamComponents) allows the TokenStreamComponents of the wrapped Analyzer to then be wrapped (such as adding a new TokenFilter to form new TokenStreamComponents.

  • Method Details

    • getPositionIncrementGap

      public int getPositionIncrementGap(String fieldName)
      Description copied from class: Analyzer
      Invoked before indexing a IndexableField instance if terms have already been added to that field. This allows custom analyzers to place an automatic position increment gap between IndexbleField instances using the same field name. The default value position increment gap is 0. With a 0 position increment gap and the typical default token position increment of 1, all terms in a field, including across IndexableField instances, are in successive positions, allowing exact PhraseQuery matches, for instance, across IndexableField instance boundaries.
      Overrides:
      getPositionIncrementGap in class Analyzer
      Parameters:
      fieldName - IndexableField name being indexed.
      Returns:
      position increment gap, added to the next token emitted from Analyzer.tokenStream(String,Reader). This value must be >= 0.

    • getOffsetGap

      public int getOffsetGap(String fieldName)
      Description copied from class: Analyzer
      Just like Analyzer.getPositionIncrementGap(java.lang.String), except for Token offsets instead. By default this returns 1. This method is only called if the field produced at least one token for indexing.
      Overrides:
      getOffsetGap in class Analyzer
      Parameters:
      fieldName - the field just indexed
      Returns:
      offset gap, added to the next token emitted from Analyzer.tokenStream(String,Reader). This value must be >= 0.

    • initReader

      public final Reader initReader(String fieldName, Reader reader)