+
−/*
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− * This Source Code Form is subject to the terms of the Mozilla Public
+
− * License, v. 2.0.  If a copy of the MPL was not distributed with this
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− * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
− *
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− * Copyright 1997 - July 2008 CWI, August 2008 - 2021 MonetDB B.V.
+
− */
+
−
+
−package org.monetdb.util;
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−
+
−import org.monetdb.jdbc.MonetConnection;
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−
+
−import java.io.BufferedReader;
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−import java.io.BufferedWriter;
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−import java.io.IOException;
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−import java.io.OutputStream;
+
−import java.nio.charset.Charset;
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−import java.nio.charset.StandardCharsets;
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−import java.nio.file.FileSystems;
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−import java.nio.file.Files;
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−import java.nio.file.Path;
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−import java.nio.file.StandardOpenOption;
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−
+
−/**
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− * Sample implementation of COPY ... INTO 'file-name' ON CLIENT handling
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− *
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− * Can be registered with {@link MonetConnection#setUploadHandler(MonetConnection.UploadHandler)}
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− * and {@link MonetConnection#setDownloadHandler(MonetConnection.DownloadHandler)}.
+
− * Implements uploads and downloads by reading and writing files on the file system.
+
− */
+
−public class FileTransferHandler implements MonetConnection.UploadHandler, MonetConnection.DownloadHandler {
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−	private final Path root;
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−	private final Charset encoding;
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−
+
−	/**
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−	 * Create a new FileTransferHandler which serves the given directory.
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−	 * @param dir directory to read and write files from
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−	 * @param encoding set this to true if all files in the directory are known to be utf-8 encoded.
+
−	 */
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−	public FileTransferHandler(final Path dir, final Charset encoding) {
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−		this.root = dir.toAbsolutePath().normalize();
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−		this.encoding = encoding;
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−	}
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−
+
−	/**
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−	 * Create a new FileTransferHandler which serves the given directory.
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−	 *
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−	 * @param dir directory to read and write files from
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−	 * @param utf8Encoded set this to true if all files in the directory are known to be utf-8 encoded.
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−	 */
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−	public FileTransferHandler(final String dir, final Charset encoding) {
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−		this(FileSystems.getDefault().getPath(dir), encoding);
+
−	}
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−
+
−	public void handleUpload(final MonetConnection.Upload handle, final String name, final boolean textMode, final long linesToSkip) throws IOException {
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−		final Path path = root.resolve(name).normalize();
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−		if (!path.startsWith(root)) {
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−			handle.sendError("File is not in upload directory");
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−			return;
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−		}
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−		if (!Files.isReadable(path)) {
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−			handle.sendError("Cannot read " + name);
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−			return;
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−		}
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−		if (!textMode) {
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−			// must upload as a byte stream
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−			handle.uploadFrom(Files.newInputStream(path));
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−		} else if (linesToSkip == 0 && utf8Encoded()) {
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−			// more efficient to upload as a byte stream
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−			handle.uploadFrom(Files.newInputStream(path));
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−		} else {
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−			// cannot upload as a byte stream, must deal with encoding
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−			final BufferedReader reader = Files.newBufferedReader(path, encoding);
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−			handle.uploadFrom(reader, linesToSkip);
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−		}
+
−	}
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−
+
−	public void handleDownload(final MonetConnection.Download handle, final String name, final boolean textMode) throws IOException {
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−		final Path path = root.resolve(name).normalize();
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−		if (!path.startsWith(root)) {
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−			handle.sendError("File is not in download directory");
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−			return;
+
−		}
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−		if (Files.exists(path)) {
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−			handle.sendError("File already exists: " + name);
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−			return;
+
−		}
+
−		if (!textMode) {
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−			// must download as a byte stream
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−			final OutputStream outputStream = Files.newOutputStream(path, StandardOpenOption.CREATE_NEW);
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−			handle.downloadTo(outputStream);
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−		} else if (utf8Encoded()) {
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−			// more efficient to download as a byte stream
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−			final OutputStream outputStream = Files.newOutputStream(path, StandardOpenOption.CREATE_NEW);
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−			handle.downloadTo(outputStream);
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−		} else {
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−			// cannot download as a byte stream, must deal with encoding
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−			final BufferedWriter writer = Files.newBufferedWriter(path, encoding, StandardOpenOption.CREATE_NEW);
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−			handle.downloadTo(writer);
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−			writer.close();
+
−		}
+
−	}
+
−
+
−	public boolean utf8Encoded() {
+
−		return encoding.equals(StandardCharsets.UTF_8);
+
−	}
+
−}