X-Git-Url: https://git.mdrn.pl/pylucene.git/blobdiff_plain/a2e61f0c04805cfcb8706176758d1283c7e3a55c..aaeed5504b982cf3545252ab528713250aa33eed:/lucene-java-3.5.0/lucene/contrib/highlighter/src/java/org/apache/lucene/search/highlight/OffsetLimitTokenFilter.java diff --git a/lucene-java-3.5.0/lucene/contrib/highlighter/src/java/org/apache/lucene/search/highlight/OffsetLimitTokenFilter.java b/lucene-java-3.5.0/lucene/contrib/highlighter/src/java/org/apache/lucene/search/highlight/OffsetLimitTokenFilter.java new file mode 100644 index 0000000..2102c28 --- /dev/null +++ b/lucene-java-3.5.0/lucene/contrib/highlighter/src/java/org/apache/lucene/search/highlight/OffsetLimitTokenFilter.java @@ -0,0 +1,57 @@ +package org.apache.lucene.search.highlight; + +/** + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +import java.io.IOException; + +import org.apache.lucene.analysis.TokenFilter; +import org.apache.lucene.analysis.TokenStream; +import org.apache.lucene.analysis.tokenattributes.OffsetAttribute; + +/** + * This TokenFilter limits the number of tokens while indexing by adding up the + * current offset. + */ +public final class OffsetLimitTokenFilter extends TokenFilter { + + private int offsetCount; + private OffsetAttribute offsetAttrib = getAttribute(OffsetAttribute.class); + private int offsetLimit; + + public OffsetLimitTokenFilter(TokenStream input, int offsetLimit) { + super(input); + this.offsetLimit = offsetLimit; + } + + @Override + public boolean incrementToken() throws IOException { + if (offsetCount < offsetLimit && input.incrementToken()) { + int offsetLength = offsetAttrib.endOffset() - offsetAttrib.startOffset(); + offsetCount += offsetLength; + return true; + } + return false; + } + + @Override + public void reset() throws IOException { + super.reset(); + offsetCount = 0; + } + +}