Package org.apache.lucene.analysis

Class Tokenizer

java.lang.Object
org.apache.lucene.util.AttributeSource
org.apache.lucene.analysis.TokenStream
org.apache.lucene.analysis.Tokenizer
All Implemented Interfaces:
Closeable, AutoCloseable
Direct Known Subclasses:
StandardTokenizer
public abstract class Tokenizer extends TokenStream
A Tokenizer is a TokenStream whose input is a Reader.

This is an abstract class; subclasses must override TokenStream.incrementToken()

NOTE: Subclasses overriding TokenStream.incrementToken() must call AttributeSource.clearAttributes() before setting attributes.

  • Field Details

    • input

      protected Reader input
      The text source for this Tokenizer.

  • Constructor Details

    • Tokenizer

      protected Tokenizer()
      Construct a tokenizer with no input, awaiting a call to setReader(java.io.Reader) to provide input.

    • Tokenizer

      protected Tokenizer(AttributeFactory factory)
      Construct a tokenizer with no input, awaiting a call to setReader(java.io.Reader) to provide input.
      Parameters:
      factory - attribute factory.

  • Method Details

    • close

      public void close() throws IOException
      Releases resources associated with this stream.

      If you override this method, always call super.close(), otherwise some internal state will not be correctly reset (e.g., Tokenizer will throw IllegalStateException on reuse).

      NOTE: The default implementation closes the input Reader, so be sure to call super.close() when overriding this method.

      Specified by:
      close in interface AutoCloseable
      Specified by:
      close in interface Closeable
      Overrides:
      close in class TokenStream
      Throws:
      IOException

    • correctOffset

      protected final int correctOffset(int currentOff)
      Return the corrected offset. If input is a CharFilter subclass this method calls CharFilter.correctOffset(int), else returns currentOff.
      Parameters:
      currentOff - offset as seen in the output
      Returns:
      corrected offset based on the input
      See Also:

    • setReader

      public final void setReader(Reader input)
      Expert: Set a new reader on the Tokenizer. Typically, an analyzer (in its tokenStream method) will use this to re-use a previously created tokenizer.

    • reset

      public void reset() throws IOException
      Description copied from class: TokenStream
      This method is called by a consumer before it begins consumption using TokenStream.incrementToken().

      Resets this stream to a clean state. Stateful implementations must implement this method so that they can be reused, just as if they had been created fresh.

      If you override this method, always call super.reset(), otherwise some internal state will not be correctly reset (e.g., Tokenizer will throw IllegalStateException on further usage).

      Overrides:
      reset in class TokenStream
      Throws:
      IOException

    • setReaderTestPoint

      protected void setReaderTestPoint()
      NOTE: This API is for internal purposes only and might change in incompatible ways in the next release.