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org.apache.lucene.analysis
public final class: PorterStemFilter [javadoc | source]
java.lang.Object
   org.apache.lucene.util.AttributeSource
      org.apache.lucene.analysis.TokenStream
         org.apache.lucene.analysis.TokenFilter
            org.apache.lucene.analysis.PorterStemFilter

All Implemented Interfaces:
    Closeable

Transforms the token stream as per the Porter stemming algorithm. Note: the input to the stemming filter must already be in lower case, so you will need to use LowerCaseFilter or LowerCaseTokenizer farther down the Tokenizer chain in order for this to work properly!

To use this filter with other analyzers, you'll want to write an Analyzer class that sets up the TokenStream chain as you want it. To use this with LowerCaseTokenizer, for example, you'd write an analyzer like this:

class MyAnalyzer extends Analyzer {
public final TokenStream tokenStream(String fieldName, Reader reader) {
return new PorterStemFilter(new LowerCaseTokenizer(reader));
}
}
Fields inherited from org.apache.lucene.analysis.TokenFilter:
input
Constructor:
 public PorterStemFilter(TokenStream in) 
Method from org.apache.lucene.analysis.PorterStemFilter Summary:
incrementToken
Methods from org.apache.lucene.analysis.TokenFilter:
close,   end,   reset
Methods from org.apache.lucene.analysis.TokenStream:
close,   end,   incrementToken,   reset
Methods from org.apache.lucene.util.AttributeSource:
addAttribute,   addAttributeImpl,   captureState,   clearAttributes,   cloneAttributes,   equals,   getAttribute,   getAttributeClassesIterator,   getAttributeFactory,   getAttributeImplsIterator,   hasAttribute,   hasAttributes,   hashCode,   restoreState,   toString
Methods from java.lang.Object:
clone,   equals,   finalize,   getClass,   hashCode,   notify,   notifyAll,   toString,   wait,   wait,   wait
Method from org.apache.lucene.analysis.PorterStemFilter Detail:
 public final boolean incrementToken() throws IOException