加快Apache Commons FTPClient传输速度

Question

我正在使用Apache Commons上传大文件，但传输速度只是使用WinSCP通过FTPClient传输速度的一小部分。如何加快传输速度？

    public boolean upload(String host, String user, String password, String directory, 
        String sourcePath, String filename) throws IOException{

    FTPClient client = new FTPClient();
    FileInputStream fis = null;

    try {
        client.connect(host);
        client.login(user, password);
        client.setControlKeepAliveTimeout(500);

        logger.info("Uploading " + sourcePath);
        fis = new FileInputStream(sourcePath);        

        //
        // Store file to server
        //
        client.changeWorkingDirectory(directory);
        client.setFileType(FTP.BINARY_FILE_TYPE);
        client.storeFile(filename, fis);
        client.logout();
        return true;
    } catch (IOException e) {
        logger.error( "Error uploading " + filename, e );
        throw e;
    } finally {
        try {
            if (fis != null) {
                fis.close();
            }
            client.disconnect();

        } catch (IOException e) {
            logger.error("Error!", e);
        }
    }         
}

Answer 1

增加缓冲区大小：

client.setBufferSize(1024000);

Answer 2

使用outputStream方法，并使用缓冲区进行传输。

InputStream inputStream = new FileInputStream(myFile);
OutputStream outputStream = ftpclient.storeFileStream(remoteFile);

byte[] bytesIn = new byte[4096];
int read = 0;

while((read = inputStream.read(bytesIn)) != -1) {
    outputStream.write(bytesIn, 0, read);
}

inputStream.close();
outputStream.close();

Answer 3

在Java1.7和Commons NET3.2中有一个已知的问题，这个错误是https://issues.apache.org/jira/browse/NET-493

如果运行这些版本，我建议首先升级到Commons Net 3.3。显然，3.4也修复了更多的性能问题。