kmall-pt/kmall-common/src/main/java/com/kmall/common/fileserver/fastdfs/UploadStream.java

package com.kmall.common.fileserver.fastdfs;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

/**
 * Upload file by stream
 *
 * @author zhouzezhong & Happy Fish / YuQing
 * @version Version 1.11
 */
public class UploadStream implements UploadCallback {
  private InputStream inputStream; //input stream for reading
  private long fileSize = 0;  //size of the uploaded file

  /**
   * constructor
   *
   * @param inputStream input stream for uploading
   * @param fileSize    size of uploaded file
   */
  public UploadStream(InputStream inputStream, long fileSize) {
    super();
    this.inputStream = inputStream;
    this.fileSize = fileSize;
  }

  /**
   * send file content callback function, be called only once when the file uploaded
   *
   * @param out output stream for writing file content
   * @return 0 success, return none zero(errno) if fail
   */
  public int send(OutputStream out) throws IOException {
    long remainBytes = fileSize;
    byte[] buff = new byte[256 * 1024];
    int bytes;
    while (remainBytes > 0) {
      try {
        if ((bytes = inputStream.read(buff, 0, remainBytes > buff.length ? buff.length : (int) remainBytes)) < 0) {
          return -1;
        }
      } catch (IOException ex) {
        ex.printStackTrace();
        return -1;
      }

      out.write(buff, 0, bytes);
      remainBytes -= bytes;
    }

    return 0;
  }
}