| /* |
| * 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.jena.dboe.base.file; |
| |
| import static java.lang.String.format; |
| |
| import java.nio.ByteBuffer; |
| import java.nio.channels.FileChannel; |
| import java.util.concurrent.atomic.AtomicLong; |
| |
| import org.apache.jena.atlas.lib.InternalErrorException; |
| import org.apache.jena.dboe.base.block.Block; |
| import org.apache.jena.dboe.base.block.BlockException; |
| import org.apache.jena.dboe.sys.FileLib; |
| import org.apache.jena.dboe.sys.Sys; |
| import org.slf4j.Logger; |
| |
| /** Support for a disk file backed FileAccess */ |
| public abstract class BlockAccessBase implements BlockAccess { |
| protected final int blockSize; |
| protected FileChannel file; |
| protected final String filename; |
| |
| protected final String label; |
| // Does this need to be tread safe? |
| // Only changes in a write transaction |
| |
| // Don't overload use of this! |
| protected final AtomicLong seq; |
| protected long numFileBlocks = -1; |
| |
| public BlockAccessBase(String filename, int blockSize) { |
| this.filename = filename; |
| this.file = FileLib.openManaged(filename); |
| this.blockSize = blockSize; |
| this.label = label(filename); |
| // This is not related to used file length in mapped mode. |
| long filesize = FileLib.size(file); |
| long longBlockSize = blockSize; |
| |
| numFileBlocks = filesize / longBlockSize; // This is not related to |
| // used file length in mapped |
| // mode. |
| seq = new AtomicLong(numFileBlocks); |
| |
| if ( numFileBlocks > Integer.MAX_VALUE ) |
| getLog().warn(format("File size (%d) exceeds tested block number limits (%d)", filesize, blockSize)); |
| |
| if ( filesize % longBlockSize != 0 ) |
| throw new BlockException(format("File size (%d) not a multiple of blocksize (%d)", filesize, blockSize)); |
| } |
| |
| /** Find path component, with extension */ |
| private static String label(String filename) { |
| int j = filename.lastIndexOf('/'); |
| if ( j < 0 ) |
| j = filename.lastIndexOf('\\'); |
| String fn = (j >= 0) ? filename.substring(j + 1) : filename; |
| return fn; |
| } |
| |
| protected abstract Logger getLog(); |
| |
| @Override |
| final public boolean isEmpty() { |
| return numFileBlocks <= 0; |
| } |
| |
| final protected void writeNotification(Block block) {} |
| |
| final protected void overwriteNotification(Block block) { |
| // Write at end => extend |
| if ( block.getId() >= numFileBlocks ) { |
| numFileBlocks = block.getId() + 1; |
| seq.set(numFileBlocks); |
| } |
| } |
| |
| final protected int allocateId() { |
| checkIfClosed(); |
| long z = seq.getAndIncrement(); |
| int id = (int)z; |
| if ( id < 0 ) { |
| String msg = format("%s : Block id has gone negative: %d (long = %d)", label, id, z); |
| throw new InternalErrorException(msg); |
| } |
| // TODO Fix this when proper free block management is introduced. |
| numFileBlocks++; |
| return id; |
| } |
| |
| @Override |
| final public long allocBoundary() { |
| checkIfClosed(); |
| return seq.get(); |
| // Underlying area is untouched. |
| } |
| |
| @Override |
| final public void resetAllocBoundary(long boundary) { |
| checkIfClosed(); |
| seq.set(boundary); |
| _resetAllocBoundary(boundary); |
| } |
| |
| protected abstract void _resetAllocBoundary(long boundary); |
| |
| @Override |
| final synchronized public boolean valid(long id) { |
| if ( id >= numFileBlocks ) |
| return false; |
| if ( id < 0 ) |
| return false; |
| return true; |
| } |
| |
| final protected void check(long id) { |
| if ( id > Integer.MAX_VALUE ) |
| throw new BlockException(format("BlockAccessBase: Id (%d) too large", id)); |
| |
| // Access to numFileBlocks not synchronized - it's only a check |
| if ( id < 0 || id >= numFileBlocks ) { |
| // Do it properly! |
| synchronized (this) { |
| if ( id < 0 || id >= numFileBlocks ) |
| throw new BlockException(format("BlockAccessBase: Bounds exception: %s: (%d,%d)", filename, id, numFileBlocks)); |
| } |
| } |
| } |
| |
| final protected void check(Block block) { |
| check(block.getId()); |
| ByteBuffer bb = block.getByteBuffer(); |
| if ( bb.capacity() != blockSize ) |
| throw new BlockException(format("BlockMgrFile: Wrong size block. Expected=%d : actual=%d", blockSize, bb.capacity())); |
| if ( bb.order() != Sys.NetworkOrder ) |
| throw new BlockException("BlockMgrFile: Wrong byte order"); |
| } |
| |
| protected void force() { |
| FileLib.sync(file); |
| } |
| |
| // @Override |
| final public boolean isClosed() { |
| return file == null; |
| } |
| |
| protected final void checkIfClosed() { |
| if ( isClosed() ) |
| getLog().error("File has been closed"); |
| } |
| |
| protected abstract void _close(); |
| |
| @Override |
| final public void close() { |
| _close(); |
| FileLib.close(file); |
| file = null; |
| } |
| |
| @Override |
| public String getLabel() { |
| return label; |
| } |
| } |