我已經將原始碼打包成一個jar，下載後匯入到你的工程中即可。如果你是用maven管理工程，可將jar包上傳到公司自己擔的私服中。jar下載地址：http://download.csdn.net/detail/xyang81/9656690

我將官方提供的sdk封裝了一個工具類，將工具類匯入工程即可使用，如下所示：  

import org.apache.commons.io.FileUtils;
import org.apache.commons.io.IOUtils;
import org.csource.common.NameValuePair;
import org.csource.fastdfs.*;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;

/**
 * <p>Description: FastDFS檔案上傳下載工具類 </p>
 * <p>Copyright: Copyright (c) 2016</p>
 *
 * @author yangxin
 * @version 1.0
 * @date 2016/10/19
 */
public class FastDFSClient {

    private static final String CONFIG_FILENAME = "src/main/resources/fdfs/fdfs_client.conf";

    private static StorageClient1 storageClient1 = null;

    // 初始化FastDFS Client
    static {
        try {
            ClientGlobal.init(CONFIG_FILENAME);
            TrackerClient trackerClient = new TrackerClient(ClientGlobal.g_tracker_group);
            TrackerServer trackerServer = trackerClient.getConnection();
            if (trackerServer == null) {
                throw new IllegalStateException("getConnection return null");
            }

            StorageServer storageServer = trackerClient.getStoreStorage(trackerServer);
            if (storageServer == null) {
                throw new IllegalStateException("getStoreStorage return null");
            }

            storageClient1 = new StorageClient1(trackerServer,storageServer);

        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * 上傳檔案
     * @param file 檔案物件
     * @param fileName 檔名
     * @return
     */
    public static String uploadFile(File file, String fileName) {
        return uploadFile(file,fileName,null);
    }

    /**
     * 上傳檔案
     * @param file 檔案物件
     * @param fileName 檔名
     * @param metaList 檔案元資料
     * @return
     */
    public static String uploadFile(File file, String fileName, Map<String,String> metaList) {
        try {
            byte[] buff = IOUtils.toByteArray(new FileInputStream(file));
            NameValuePair[] nameValuePairs = null;
            if (metaList != null) {
                nameValuePairs = new NameValuePair[metaList.size()];
                int index = 0;
                for (Iterator<Map.Entry<String,String>> iterator = metaList.entrySet().iterator(); iterator.hasNext();) {
                    Map.Entry<String,String> entry = iterator.next();
                    String name = entry.getKey();
                    String value = entry.getValue();
                    nameValuePairs[index++] = new NameValuePair(name,value);
                }
            }
            return storageClient1.upload_file1(buff,FileUtils.getExtension(fileName),nameValuePairs);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }

    /**
     * 獲取檔案元資料
     * @param fileId 檔案ID
     * @return
     */
    public static Map<String,String> getFileMetadata(String fileId) {
        try {
            NameValuePair[] metaList = storageClient1.get_metadata1(fileId);
            if (metaList != null) {
                HashMap<String,String> map = new HashMap<String, String>();
                for (NameValuePair metaItem : metaList) {
                    map.put(metaItem.getName(),metaItem.getValue());
                }
                return map;
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }

    /**
     * 刪除檔案
     * @param fileId 檔案ID
     * @return 刪除失敗返回-1，否則返回0
     */
    public static int deleteFile(String fileId) {
        try {
            return storageClient1.delete_file1(fileId);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return -1;
    }

    /**
     * 下載檔案
     * @param fileId 檔案ID（上傳檔案成功後返回的ID）
     * @param outFile 檔案下載儲存位置
     * @return
     */
    public static int downloadFile(String fileId, File outFile) {
        FileOutputStream fos = null;
        try {
            byte[] content = storageClient1.download_file1(fileId);
            fos = new FileOutputStream(outFile);
            IOUtils.copy(content,fos);
            return 0;
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            if (fos != null) {
                try {
                    fos.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        return -1;
    }

}
 

Java客戶端配置檔案（fdfs_client.conf）：

connect_timeout = 10                    # 連線tracker伺服器超時時長
network_timeout = 30                    # socket連線超時時長
charset = UTF-8                         # 檔案內容編碼
http.tracker_http_port = 8888           # tracker伺服器埠
http.anti_steal_token = no
http.secret_key = FastDFS1234567890     

tracker_server = 192.168.0.200:22122    # tracker伺服器IP和埠（可以寫多個）
#tracker_server = xxxx:xxx
 

Java客戶端檔案上傳、下載、刪除和元資料獲取測試：

import org.junit.Test;

import java.io.File;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;

/**
 * <p>Description: </p>
 * <p>Copyright: Copyright (c) 2016</p>
 *
 * @author yangxin
 * @version 1.0
 * @date 2016/10/19
 */
public class FastDFSClientTest {

    /**
     * 檔案上傳測試
     */
    @Test
    public void testUpload() {
        File file = new File("C:\\Users\\yangfang\\Pictures\\angularjs_share.jpg");
        Map<String,String> metaList = new HashMap<String, String>();
        metaList.put("width","1024");
        metaList.put("height","768");
        metaList.put("author","楊信");
        metaList.put("date","20161018");
        String fid = FastDFSClient.uploadFile(file,file.getName(),metaList);
        System.out.println("upload local file " + file.getPath() + " ok, fileid=" + fid);
        //上傳成功返回的檔案ID： group1/M00/00/00/wKgAyVgFk9aAB8hwAA-8Q6_7tHw351.jpg
    }

    /**
     * 檔案下載測試
     */
    @Test
    public void testDownload() {
        int r = FastDFSClient.downloadFile("group1/M00/00/00/wKgAyVgFk9aAB8hwAA-8Q6_7tHw351.jpg", new File("DownloadFile_fid.jpg"));
        System.out.println(r == 0 ? "下載成功" : "下載失敗");
    }

    /**
     * 獲取檔案元資料測試
     */
    @Test
    public void testGetFileMetadata() {
        Map<String,String> metaList = FastDFSClient.getFileMetadata("group1/M00/00/00/wKgAyVgFk9aAB8hwAA-8Q6_7tHw351.jpg");
        for (Iterator<Map.Entry<String,String>>  iterator = metaList.entrySet().iterator(); iterator.hasNext();) {
            Map.Entry<String,String> entry = iterator.next();
            String name = entry.getKey();
            String value = entry.getValue();
            System.out.println(name + " = " + value );
        }
    }

    /**
     * 檔案刪除測試
     */
    @Test
    public void testDelete() {
        int r = FastDFSClient.deleteFile("group1/M00/00/00/wKgAyVgFk9aAB8hwAA-8Q6_7tHw351.jpg");
        System.out.println(r == 0 ? "刪除成功" : "刪除失敗");
    }
}