/* * 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. */ package org.apache.cassandra.db.rows; import java.nio.ByteBuffer; import java.util.*; import org.apache.cassandra.config.CFMetaData; import org.apache.cassandra.config.ColumnDefinition; import org.apache.cassandra.db.*; import org.apache.cassandra.db.context.CounterContext; import org.apache.cassandra.db.filter.ColumnFilter; public class SerializationHelper { /** * Flag affecting deserialization behavior (this only affect counters in practice). * - LOCAL: for deserialization of local data (Expired columns are * converted to tombstones (to gain disk space)). * - FROM_REMOTE: for deserialization of data received from remote hosts * (Expired columns are converted to tombstone and counters have * their delta cleared) * - PRESERVE_SIZE: used when no transformation must be performed, i.e, * when we must ensure that deserializing and reserializing the * result yield the exact same bytes. Streaming uses this. */ public enum Flag { LOCAL, FROM_REMOTE, PRESERVE_SIZE } private final Flag flag; public final int version; private final ColumnFilter columnsToFetch; private ColumnFilter.Tester tester; private final Map<ByteBuffer, CFMetaData.DroppedColumn> droppedColumns; private CFMetaData.DroppedColumn currentDroppedComplex; public SerializationHelper(CFMetaData metadata, int version, Flag flag, ColumnFilter columnsToFetch) { this.flag = flag; this.version = version; this.columnsToFetch = columnsToFetch; this.droppedColumns = metadata.getDroppedColumns(); } public SerializationHelper(CFMetaData metadata, int version, Flag flag) { this(metadata, version, flag, null); } public Columns fetchedStaticColumns(SerializationHeader header) { return columnsToFetch == null ? header.columns().statics : columnsToFetch.fetchedColumns().statics; } public Columns fetchedRegularColumns(SerializationHeader header) { return columnsToFetch == null ? header.columns().regulars : columnsToFetch.fetchedColumns().regulars; } public boolean includes(ColumnDefinition column) { return columnsToFetch == null || columnsToFetch.includes(column); } public boolean includes(CellPath path) { return path == null || tester == null || tester.includes(path); } public boolean canSkipValue(ColumnDefinition column) { return columnsToFetch != null && columnsToFetch.canSkipValue(column); } public boolean canSkipValue(CellPath path) { return path != null && tester != null && tester.canSkipValue(path); } public void startOfComplexColumn(ColumnDefinition column) { this.tester = columnsToFetch == null ? null : columnsToFetch.newTester(column); this.currentDroppedComplex = droppedColumns.get(column.name.bytes); } public void endOfComplexColumn() { this.tester = null; } public boolean isDropped(Cell cell, boolean isComplex) { CFMetaData.DroppedColumn dropped = isComplex ? currentDroppedComplex : droppedColumns.get(cell.column().name.bytes); return dropped != null && cell.timestamp() <= dropped.droppedTime; } public boolean isDroppedComplexDeletion(DeletionTime complexDeletion) { return currentDroppedComplex != null && complexDeletion.markedForDeleteAt() <= currentDroppedComplex.droppedTime; } public ByteBuffer maybeClearCounterValue(ByteBuffer value) { return flag == Flag.FROM_REMOTE || (flag == Flag.LOCAL && CounterContext.instance().shouldClearLocal(value)) ? CounterContext.instance().clearAllLocal(value) : value; } }