java fastDfs 分片追加上传

FastDFS是一个开源的轻量级分布式文件系统，可以方便地进行文件的存储和管理。FastDFS支持文件上传、下载、删除、修改、追加等操作，支持文件的分片存储和自动备份。下面是Java实现FastDFS分片追加上传的示例代码：

import org.csource.common.NameValuePair;
import org.csource.fastdfs.*;

import java.io.*;

public class FastDFSClient {
 
    private static final String CONF_FILENAME = "fdfs_client.conf";
 
    static {
        try {
            ClientGlobal.init(CONF_FILENAME);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
 
    public static String uploadFile(String filePath) throws Exception {
        File file = new File(filePath);
        FileInputStream fis = new FileInputStream(file);
        byte[] fileBuff = null;
        if (fis != null) {
            int len = fis.available();
            fileBuff = new byte[len];
            fis.read(fileBuff);
        }
        return uploadFile(fileBuff, file.getName());
    }
 
    public static String uploadFile(byte[] fileBuff, String fileName) throws Exception {
        TrackerClient trackerClient = new TrackerClient();
        TrackerServer trackerServer = trackerClient.getConnection();
        StorageServer storageServer = null;
        StorageClient1 storageClient = new StorageClient1(trackerServer, storageServer);
        NameValuePair[] metaList = new NameValuePair[1];
        metaList[0] = new NameValuePair("fileName", fileName);
        String fileId = storageClient.upload_file1(fileBuff, getFileExt(fileName), metaList);
        trackerServer.close();
        return fileId;
    }
 
    public static void appendFile(String fileId, String filePath) throws Exception {
        File file = new File(filePath);
        FileInputStream fis = new FileInputStream(file);
        byte[] fileBuff = null;
        if (fis != null) {
            int len = fis.available();
            fileBuff = new byte[len];
            fis.read(fileBuff);
        }
        appendFile(fileId, fileBuff);
    }
 
    public static void appendFile(String fileId, byte[] fileBuff) throws Exception {
        TrackerClient trackerClient = new TrackerClient();
        TrackerServer trackerServer = trackerClient.getConnection();
        StorageServer storageServer = null;
        StorageClient1 storageClient = new StorageClient1(trackerServer, storageServer);
        int result = storageClient.append_file1(fileId, fileBuff);
        trackerServer.close();
        if (result != 0) {
            throw new Exception("append file error, error code: " + result);
        }
    }
 
    private static String getFileExt(String fileName) {
        if (fileName.contains(".")) {
            return fileName.substring(fileName.lastIndexOf(".") + 1);
        } else {
            return "";
        }
    }
}

其中，uploadFile方法用于上传文件，appendFile方法用于追加文件。在上传文件时，我们可以通过metaList参数设置文件的元数据，如文件名等信息。在追加文件时，我们需要传入文件的ID和追加的文件内容。需要注意的是，FastDFS的文件上传和追加操作都是基于文件的ID进行的。因此，在上传文件时，我们需要获取到文件的ID，以便在追加文件时使用。