使用Apache Commons VFS，如何监控文件传输的进度。我需要能够通过上传和下载来完成。我还需要监控HTTP，FTP，SFTP和FTPS的进度。我在文档中找不到任何关于它的内容。
答案 0 :(得分：1)
可以通过从VFS获取输入和输出流来完成。以下示例使用commons-net中的实用程序类（VFS的依赖项）来管理复制和进度监视。您也可以手动完成。
import org.apache.commons.net.io.Util;
import org.apache.commons.net.io.CopyStreamListener;
private void copy(FileObject sourceFile, FileObject destinationFile, CopyStreamListener progressMonitor) throws IOException {
InputStream sourceFileIn = sourceFile.getContent().getInputStream();
try {
OutputStream destinationFileOut = destinationFile.getContent().getOutputStream();
try {
Util.copyStream(sourceFileIn, destinationFileOut, Util.DEFAULT_COPY_BUFFER_SIZE, sourceFile.getContent().getSize(), progressMonitor);
} finally {
destinationFileOut.close();
}
} finally {
sourceFileIn.close();
}
}
答案 1 :(得分：0)
提议的解决方案有点不对劲，而且有点“弱”。让我们试试更整洁的！
注意：以下代码需要 JDK 16。
举一个使用标准启动的复制操作示例：
final var manager = VFS.getManager();
final var origin = manager.resolveFile(originUri.toString(), fileSystemOptions);
final var destination = manager.resolveFile(destinationUri.toString(), fileSystemOptions);
destination.copyFrom(origin, Selectors.SELECT_ALL);
简单地用我们称为 FileObject 的自定义委托实现包装目标 ProgressFileObject，它也接受 ProgressListener：
final var listener = new ProgressListener() {
@Override
public void started() {
System.out.println("Started");
}
@Override
public void completed() {
System.out.println("Completed");
}
@Override
public void failed(@NotNull final Exception e) {
System.out.println("Failed: " + e.getMessage());
}
@Override
public void progress(@NotNull final ProgressEvent event) {
final var out = "%d\t\t\t%d\t\t\tFile: %s".formatted(
event.totalBytes(),
event.totalTransferredBytes(),
event.lastFileDestinationPath()
);
System.out.println(out);
}
};
final var progressDestination = new ProgressFileObject(destination, listener);
progressFileObject.copyFrom(origin, Selectors.SELECT_ALL);
这将导致一个文件夹：
Started
4648320 119391 File: /test_dir/AN/ANI0.evt
4648320 119511 File: /test_dir/AN/ANI0.hpj
4648320 119584 File: /test_dir/AN/ANI0.ipf
4648320 119585 File: /test_dir/AN/ANI0.ipm
4648320 1907060 File: /test_dir/AN/ANI0.LST
4648320 1907253 File: /test_dir/AN/ANI0.MRG
4648320 2472700 File: /test_dir/AN/ANI0.ODF
4648320 2472707 File: /test_dir/AN/ANI0.ph
4648320 2473421 File: /test_dir/AN/ANI0.rbj
4648320 2473547 File: /test_dir/AN/ANI0.rc
4648320 2473708 File: /test_dir/AN/ANI0.rst
4648320 2474813 File: /test_dir/AN/ANI0.rtf
4648320 2474814 File: /test_dir/AN/ANI0.txc
4648320 2474819 File: /test_dir/AN/ANI0.txm
4648320 2474820 File: /test_dir/AN/ANI0.vpf
4648320 2829348 File: /test_dir/AN/ANI0.VPG
4648320 2829466 File: /test_dir/AN/P0000001.rc
4648320 2829592 File: /test_dir/AN/P0000002.rc
4648320 4648275 File: /test_dir/AN/VPGSAV55.C2T
4648320 4648320 File: /test_dir/AN/VRPGWIN.RC
Completed
以下是 ProgressFileObject、ProgressListener 和 ProgressEvent 来源：
/**
* @author Edoardo Luppi
*/
public class ProgressFileObject extends DecoratedFileObject {
private final FileObject fileObject;
private final ProgressListener listener;
public ProgressFileObject(
@NotNull final FileObject fileObject,
@NotNull final ProgressListener listener) {
super(fileObject);
this.fileObject = fileObject;
this.listener = listener;
}
@Override
public void copyFrom(final FileObject file, final FileSelector selector) throws FileSystemException {
if (!FileObjectUtils.exists(file)) {
final var exception = new FileSystemException("vfs.provider/copy-missing-file.error", file);
listener.failed(exception);
throw exception;
}
listener.started();
// Locate the files to copy across
final List<FileObject> files = new ArrayList<>();
file.findFiles(selector, false, files);
// Calculate the total bytes that will be copied
var totalBytes = 0L;
for (final var srcFile : files) {
if (srcFile.getType().hasContent()) {
totalBytes += srcFile.getContent().getSize();
}
}
var totalTransferredBytes = 0L;
// Copy everything across
for (final var srcFile : files) {
// Determine the destination file
final var relPath = file.getName().getRelativeName(srcFile.getName());
final var destFile = resolveFile(relPath, NameScope.DESCENDENT_OR_SELF);
// Clean up the destination file, if necessary
if (FileObjectUtils.exists(destFile) && destFile.getType() != srcFile.getType()) {
// The destination file exists, and is not of the same type, so delete it
destFile.deleteAll();
}
// Copy across
try {
if (srcFile.getType().hasContent()) {
try (final var content = srcFile.getContent()) {
final var fileTransferredBytes = content.write(destFile);
totalTransferredBytes += fileTransferredBytes;
final var event = new ProgressEvent(
totalBytes,
totalTransferredBytes,
fileTransferredBytes,
srcFile.getName().getPath(),
destFile.getName().getPath()
);
listener.progress(event);
}
} else if (srcFile.getType().hasChildren()) {
destFile.createFolder();
}
} catch (final IOException e) {
final var exception = new FileSystemException("vfs.provider/copy-file.error", e, srcFile, destFile);
listener.failed(exception);
throw exception;
}
}
listener.completed();
}
@Override
public URI getURI() {
return fileObject.getURI();
}
@Override
public Path getPath() {
return fileObject.getPath();
}
@Override
public boolean isSymbolicLink() throws FileSystemException {
return fileObject.isSymbolicLink();
}
@Override
public void forEach(final Consumer<? super FileObject> action) {
fileObject.forEach(action);
}
@Override
public Spliterator<FileObject> spliterator() {
return fileObject.spliterator();
}
@Override
public int hashCode() {
return fileObject.hashCode();
}
@Override
public boolean equals(final Object obj) {
return fileObject.equals(obj);
}
@Override
public String toString() {
return fileObject.toString();
}
public interface ProgressListener {
void started();
void completed();
void failed(@NotNull final Exception e);
void progress(@NotNull final ProgressEvent event);
}
public record ProgressEvent(
long totalBytes,
long totalTransferredBytes,
long lastFileTransferredBytes,
String lastFileOriginPath,
String lastFileDestinationPath
) {}
}