Class WordTokenFilter

  extended by org.apache.lucene.util.AttributeSource
      extended by org.apache.lucene.analysis.TokenStream
          extended by org.apache.lucene.analysis.TokenFilter
              extended by

public final class WordTokenFilter
extends TokenFilter

A TokenFilter that breaks sentences into words.

WARNING: The status of the analyzers/smartcn package is experimental. The APIs and file formats introduced here might change in the future and will not be supported anymore in such a case.

Nested Class Summary
Nested classes/interfaces inherited from class org.apache.lucene.util.AttributeSource
AttributeSource.AttributeFactory, AttributeSource.State
Field Summary
Fields inherited from class org.apache.lucene.analysis.TokenFilter
Constructor Summary
WordTokenFilter(TokenStream in)
          Construct a new WordTokenizer.
Method Summary
 boolean incrementToken()
          Consumers (i.e., IndexWriter) use this method to advance the stream to the next token.
 void reset()
          Reset the filter as well as the input TokenStream.
Methods inherited from class org.apache.lucene.analysis.TokenFilter
close, end
Methods inherited from class org.apache.lucene.analysis.TokenStream
getOnlyUseNewAPI, next, next, setOnlyUseNewAPI
Methods inherited from class org.apache.lucene.util.AttributeSource
addAttribute, addAttributeImpl, captureState, clearAttributes, cloneAttributes, equals, getAttribute, getAttributeClassesIterator, getAttributeFactory, getAttributeImplsIterator, hasAttribute, hasAttributes, hashCode, restoreState, toString
Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail


public WordTokenFilter(TokenStream in)
Construct a new WordTokenizer.

in - TokenStream of sentences
Method Detail


public boolean incrementToken()
                       throws IOException
Description copied from class: TokenStream
Consumers (i.e., IndexWriter) use this method to advance the stream to the next token. Implementing classes must implement this method and update the appropriate AttributeImpls with the attributes of the next token.

The producer must make no assumptions about the attributes after the method has been returned: the caller may arbitrarily change it. If the producer needs to preserve the state for subsequent calls, it can use AttributeSource.captureState() to create a copy of the current attribute state.

This method is called for every token of a document, so an efficient implementation is crucial for good performance. To avoid calls to AttributeSource.addAttribute(Class) and AttributeSource.getAttribute(Class) or downcasts, references to all AttributeImpls that this stream uses should be retrieved during instantiation.

To ensure that filters and consumers know which attributes are available, the attributes must be added during instantiation. Filters and consumers are not required to check for availability of attributes in TokenStream.incrementToken().

incrementToken in class TokenStream
false for end of stream; true otherwise

Note that this method will be defined abstract in Lucene 3.0.



public void reset()
           throws IOException
Description copied from class: TokenFilter
Reset the filter as well as the input TokenStream.

reset in class TokenFilter

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