/**
* 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.drill.exec.store;
import io.netty.buffer.ByteBuf;
import io.netty.buffer.ByteBufInputStream;
import io.netty.buffer.UnpooledByteBufAllocator;
import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.URI;
import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.fs.FSDataOutputStream;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.fs.PositionedReadable;
import org.apache.hadoop.fs.Seekable;
import org.apache.hadoop.fs.permission.FsPermission;
import org.apache.hadoop.util.Progressable;
public class CachedSingleFileSystem extends FileSystem{
private ByteBuf file;
private String path;
public CachedSingleFileSystem(String path) throws IOException{
this.path = path;
File f = new File(path);
long length = f.length();
if(length > Integer.MAX_VALUE) throw new UnsupportedOperationException("Cached file system only supports files of less than 2GB.");
System.out.println(length);
try(InputStream is = new BufferedInputStream(new FileInputStream(path))){
byte[] buffer = new byte[64*1024];
this.file = UnpooledByteBufAllocator.DEFAULT.directBuffer((int) length);
int read;
while( (read = is.read(buffer)) > 0){
file.writeBytes(buffer, 0, read);
}
}
}
public void close() throws IOException{
file.release();
super.close();
}
@Override
public FSDataOutputStream append(Path arg0, int arg1, Progressable arg2) throws IOException {
throw new UnsupportedOperationException();
}
@Override
public FSDataOutputStream create(Path arg0, FsPermission arg1, boolean arg2, int arg3, short arg4, long arg5,
Progressable arg6) throws IOException {
throw new UnsupportedOperationException();
}
@Override
public boolean delete(Path arg0) throws IOException {
throw new UnsupportedOperationException();
}
@Override
public boolean delete(Path arg0, boolean arg1) throws IOException {
throw new UnsupportedOperationException();
}
@Override
public FileStatus getFileStatus(Path arg0) throws IOException {
throw new UnsupportedOperationException();
}
@Override
public URI getUri() {
throw new UnsupportedOperationException();
}
@Override
public Path getWorkingDirectory() {
throw new UnsupportedOperationException();
}
@Override
public FileStatus[] listStatus(Path arg0) throws IOException {
throw new UnsupportedOperationException();
}
@Override
public boolean mkdirs(Path path, FsPermission arg1) throws IOException {
throw new UnsupportedOperationException();
}
@Override
public FSDataInputStream open(Path path, int arg1) throws IOException {
if(!path.toString().equals(this.path)) throw new IOException(String.format("You requested file %s but this cached single file system only has the file %s.", path.toString(), this.path));
return new FSDataInputStream(new CachedFSDataInputStream(file.slice()));
}
@Override
public boolean rename(Path arg0, Path arg1) throws IOException {
throw new UnsupportedOperationException();
}
@Override
public void setWorkingDirectory(Path arg0) {
throw new UnsupportedOperationException();
}
private class CachedFSDataInputStream extends ByteBufInputStream implements Seekable, PositionedReadable{
private ByteBuf buf;
public CachedFSDataInputStream(ByteBuf buffer) {
super(buffer);
this.buf = buffer;
}
@Override
public long getPos() throws IOException {
return buf.readerIndex();
}
@Override
public void seek(long arg0) throws IOException {
buf.readerIndex((int) arg0);
}
@Override
public boolean seekToNewSource(long arg0) throws IOException {
return false;
}
@Override
public int read(long pos, byte[] buffer, int offset, int length) throws IOException {
ByteBuf local = buf.slice( (int) pos, (int) Math.min( buf.capacity() - pos, length));
local.readBytes(buffer, offset, buf.capacity());
return buf.capacity();
}
@Override
public void readFully(long pos, byte[] buffer) throws IOException {
readFully(pos, buffer, 0, buffer.length);
}
@Override
public void readFully(long pos, byte[] buffer, int offset, int length) throws IOException {
if(length + pos > buf.capacity()) throw new IOException("Read was too big.");
read(pos, buffer, offset, length);
}
}
}