pylucene 3.5.0-3

[pylucene.git] / lucene-java-3.5.0 / lucene / src / java / org / apache / lucene / search / Filter.java

diff --git a/lucene-java-3.5.0/lucene/src/java/org/apache/lucene/search/Filter.java b/lucene-java-3.5.0/lucene/src/java/org/apache/lucene/search/Filter.java
new file mode 100644 (file)
index 0000000..bf63bda
--- /dev/null
+++ b/lucene-java-3.5.0/lucene/src/java/org/apache/lucene/search/Filter.java
@@ -0,0 +1,53 @@
+package org.apache.lucene.search;
+
+/**
+ * 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.index.IndexReader;
+import org.apache.lucene.util.DocIdBitSet;
+
+/** 
+ *  Abstract base class for restricting which documents may
+ *  be returned during searching.
+ */
+public abstract class Filter implements java.io.Serializable {
+  
+  /**
+   * Creates a {@link DocIdSet} enumerating the documents that should be
+   * permitted in search results. <b>NOTE:</b> null can be
+   * returned if no documents are accepted by this Filter.
+   * <p>
+   * Note: This method will be called once per segment in
+   * the index during searching.  The returned {@link DocIdSet}
+   * must refer to document IDs for that segment, not for
+   * the top-level reader.
+   * 
+   * @param reader a {@link IndexReader} instance opened on the index currently
+   *         searched on. Note, it is likely that the provided reader does not
+   *         represent the whole underlying index i.e. if the index has more than
+   *         one segment the given reader only represents a single segment.
+   *          
+   * @return a DocIdSet that provides the documents which should be permitted or
+   *         prohibited in search results. <b>NOTE:</b> null can be returned if
+   *         no documents will be accepted by this Filter.
+   * 
+   * @see DocIdBitSet
+   */
+  public abstract DocIdSet getDocIdSet(IndexReader reader) throws IOException;
+}