java ftp上传大文件 并打印上传进度信息 百分比

以下是Java代码示例，演示如何上传大文件到FTP服务器并打印上传进度信息（百分比）：

import java.io.*;
import org.apache.commons.net.ftp.*;

public class FTPUploader {
    private FTPClient ftpClient;

    public FTPUploader() {
        ftpClient = new FTPClient();
    }

    public void uploadFile(String host, String port, String username, String password, String remotePath, String localPath) throws IOException {
        int reply;
        ftpClient.connect(host, Integer.parseInt(port));
        ftpClient.login(username, password);
        reply = ftpClient.getReplyCode();
        if (!FTPReply.isPositiveCompletion(reply)) {
            ftpClient.disconnect();
            throw new IOException("Failed to connect to FTP Server");
        }

        ftpClient.enterLocalPassiveMode();
        ftpClient.setFileType(FTP.BINARY_FILE_TYPE);
        ftpClient.changeWorkingDirectory(remotePath);

        File localFile = new File(localPath);
        long fileSize = localFile.length();
        long uploadedSize = 0;
        InputStream inputStream = new FileInputStream(localFile);

        OutputStream outputStream = ftpClient.storeFileStream(localFile.getName());
        byte[] buffer = new byte[1024];
        int bytesRead;
        long startTime = System.currentTimeMillis();
        long currentTime = startTime;
        while ((bytesRead = inputStream.read(buffer)) != -1) {
            outputStream.write(buffer, 0, bytesRead);
            uploadedSize += bytesRead;
            int progress = (int) ((uploadedSize / (float) fileSize) * 100);
            long elapsedTime = System.currentTimeMillis() - currentTime;
            if (elapsedTime > 1000) { // 每秒钟打印一次上传进度信息
                System.out.println("File upload progress: " + progress + "%");
                currentTime = System.currentTimeMillis();
            }
        }
        inputStream.close();
        outputStream.close();

        boolean completed = ftpClient.completePendingCommand();
        if (completed) {
            long endTime = System.currentTimeMillis();
            System.out.println("File uploaded successfully in " + (endTime - startTime) + " ms");
        }
    }

    public void disconnect() throws IOException {
        if (ftpClient.isConnected()) {
            ftpClient.logout();
            ftpClient.disconnect();
        }
    }
}

要使用此类上传文件，请执行以下步骤：

String host = "ftp.example.com";
String port = "21";
String username = "username";
String password = "password";
String remotePath = "/remote/path";
String localPath = "/local/path/file.txt";

FTPUploader uploader = new FTPUploader();
uploader.uploadFile(host, port, username, password, remotePath, localPath);
uploader.disconnect();

请注意，此示例代码仅适用于上传二进制文件。如果您需要上传文本文件，请更改以下行：

ftpClient.setFileType(FTP.BINARY_FILE_TYPE);

为：

ftpClient.setFileType(FTP.ASCII_FILE_TYPE);