80 lines
3.0 KiB
Java
80 lines
3.0 KiB
Java
/*
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* Licensed to the Apache Software Foundation (ASF) under one
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* or more contributor license agreements. See the NOTICE file
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* distributed with this work for additional information
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* regarding copyright ownership. The ASF licenses this file
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* to you under the Apache License, Version 2.0 (the
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* "License"); you may not use this file except in compliance
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* with the License. You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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package org.apache.cassandra.db.index.keys;
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import java.nio.ByteBuffer;
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import java.util.Set;
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import org.apache.cassandra.db.Cell;
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import org.apache.cassandra.db.composites.CellName;
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import org.apache.cassandra.db.composites.CellNames;
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import org.apache.cassandra.db.ColumnFamily;
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import org.apache.cassandra.db.index.AbstractSimplePerColumnSecondaryIndex;
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import org.apache.cassandra.db.index.SecondaryIndexSearcher;
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import org.apache.cassandra.db.marshal.AbstractType;
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import org.apache.cassandra.exceptions.ConfigurationException;
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/**
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* Implements a secondary index for a column family using a second column family.
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* The design uses inverted index http://en.wikipedia.org/wiki/Inverted_index.
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* The row key is the indexed value. For example, if we're indexing a column named
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* city, the index value of city is the row key.
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* The column names are the keys of the records. To see a detailed example, please
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* refer to wikipedia.
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*/
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public class KeysIndex extends AbstractSimplePerColumnSecondaryIndex
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{
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protected ByteBuffer getIndexedValue(ByteBuffer rowKey, Cell cell)
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{
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return cell.value();
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}
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protected CellName makeIndexColumnName(ByteBuffer rowKey, Cell cell)
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{
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return CellNames.simpleDense(rowKey);
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}
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public SecondaryIndexSearcher createSecondaryIndexSearcher(Set<ByteBuffer> columns)
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{
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return new KeysSearcher(baseCfs.indexManager, columns);
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}
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public boolean isIndexEntryStale(ByteBuffer indexedValue, ColumnFamily data, long now)
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{
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Cell cell = data.getColumn(data.getComparator().makeCellName(columnDef.name.bytes));
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return cell == null || !cell.isLive(now) || columnDef.type.compare(indexedValue, cell.value()) != 0;
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}
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public void validateOptions() throws ConfigurationException
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{
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// no options used
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}
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public boolean indexes(CellName name)
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{
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// This consider the full cellName directly
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AbstractType<?> comparator = baseCfs.metadata.getColumnDefinitionComparator(columnDef);
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return comparator.compare(columnDef.name.bytes, name.toByteBuffer()) == 0;
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}
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protected AbstractType getExpressionComparator()
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{
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return baseCfs.getComparator().asAbstractType();
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}
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}
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