X-Git-Url: https://git.mdrn.pl/pylucene.git/blobdiff_plain/a2e61f0c04805cfcb8706176758d1283c7e3a55c..aaeed5504b982cf3545252ab528713250aa33eed:/lucene-java-3.5.0/lucene/src/java/org/apache/lucene/search/spans/Spans.java diff --git a/lucene-java-3.5.0/lucene/src/java/org/apache/lucene/search/spans/Spans.java b/lucene-java-3.5.0/lucene/src/java/org/apache/lucene/search/spans/Spans.java new file mode 100644 index 0000000..04c38e6 --- /dev/null +++ b/lucene-java-3.5.0/lucene/src/java/org/apache/lucene/search/spans/Spans.java @@ -0,0 +1,87 @@ +package org.apache.lucene.search.spans; + +/** + * 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 java.util.Collection; + +/** Expert: an enumeration of span matches. Used to implement span searching. + * Each span represents a range of term positions within a document. Matches + * are enumerated in order, by increasing document number, within that by + * increasing start position and finally by increasing end position. */ +public abstract class Spans { + /** Move to the next match, returning true iff any such exists. */ + public abstract boolean next() throws IOException; + + /** Skips to the first match beyond the current, whose document number is + * greater than or equal to target.

Returns true iff there is such + * a match.

Behaves as if written:

+   *   boolean skipTo(int target) {
+   *     do {
+   *       if (!next())
+   * 	     return false;
+   *     } while (target > doc());
+   *     return true;
+   *   }
+   * 
+ * Most implementations are considerably more efficient than that. + */ + public abstract boolean skipTo(int target) throws IOException; + + /** Returns the document number of the current match. Initially invalid. */ + public abstract int doc(); + + /** Returns the start position of the current match. Initially invalid. */ + public abstract int start(); + + /** Returns the end position of the current match. Initially invalid. */ + public abstract int end(); + + /** + * Returns the payload data for the current span. + * This is invalid until {@link #next()} is called for + * the first time. + * This method must not be called more than once after each call + * of {@link #next()}. However, most payloads are loaded lazily, + * so if the payload data for the current position is not needed, + * this method may not be called at all for performance reasons. An ordered + * SpanQuery does not lazy load, so if you have payloads in your index and + * you do not want ordered SpanNearQuerys to collect payloads, you can + * disable collection with a constructor option.
+ *
+ * Note that the return type is a collection, thus the ordering should not be relied upon. + *
+ * @lucene.experimental + * + * @return a List of byte arrays containing the data of this payload, otherwise null if isPayloadAvailable is false + * @throws java.io.IOException + */ + // TODO: Remove warning after API has been finalized + public abstract Collection getPayload() throws IOException; + + /** + * Checks if a payload can be loaded at this position. + *

+ * Payloads can only be loaded once per call to + * {@link #next()}. + * + * @return true if there is a payload available at this position that can be loaded + */ + public abstract boolean isPayloadAvailable(); + +}