com.lithium.flow.shell.sshj.SshjDownload.java Source code

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Here is the source code for com.lithium.flow.shell.sshj.SshjDownload.java

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/*
 * Copyright 2015 Lithium Technologies, Inc.
 *
 * Licensed 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 com.lithium.flow.shell.sshj;

import static com.google.common.base.Preconditions.checkNotNull;

import com.lithium.flow.util.Logs;
import com.lithium.flow.util.Sleep;

import java.io.IOException;
import java.io.OutputStream;
import java.io.PipedInputStream;
import java.io.PipedOutputStream;
import java.util.concurrent.CountDownLatch;

import javax.annotation.Nonnull;

import org.apache.commons.io.IOUtils;
import org.slf4j.Logger;

import net.schmizz.sshj.sftp.SFTPClient;
import net.schmizz.sshj.xfer.LocalDestFile;

/**
 * @author Matt Ayres
 */
public class SshjDownload implements LocalDestFile, Runnable {
    private static final Logger log = Logs.getLogger();

    private final SFTPClient sftp;
    private final String path;
    private final PipedInputStream pipeIn;
    private final PipedOutputStream pipeOut;
    private final CountDownLatch latch = new CountDownLatch(1);

    public SshjDownload(@Nonnull SFTPClient sftp, @Nonnull String path) throws IOException {
        this.sftp = checkNotNull(sftp);
        this.path = checkNotNull(path);

        pipeIn = new PipedInputStream() {
            @Override
            public void close() throws IOException {
                try {
                    super.close();
                } finally {
                    Sleep.softly(latch::await);
                }
            }
        };
        pipeOut = new PipedOutputStream(pipeIn);

        new Thread(this).start();
    }

    @Nonnull
    public PipedInputStream getInputStream() {
        return pipeIn;
    }

    @Override
    public void run() {
        try {
            sftp.get(path, this);
        } catch (IOException e) {
            log.warn("download failed: {}", path, e);
        } finally {
            latch.countDown();
            IOUtils.closeQuietly(pipeIn);
            IOUtils.closeQuietly(pipeOut);
        }
    }

    @Override
    public OutputStream getOutputStream() throws IOException {
        return pipeOut;
    }

    @Override
    public LocalDestFile getChild(String name) {
        throw new UnsupportedOperationException();
    }

    @Override
    public LocalDestFile getTargetFile(String filename) throws IOException {
        return this;
    }

    @Override
    public LocalDestFile getTargetDirectory(String dirname) throws IOException {
        throw new UnsupportedOperationException();
    }

    @Override
    public void setPermissions(int perms) throws IOException {
    }

    @Override
    public void setLastAccessedTime(long t) throws IOException {
    }

    @Override
    public void setLastModifiedTime(long t) throws IOException {
    }
}