當我使用httpurlconnecion下載文件時，java會消耗大量內存內存？爲什麼？

Question

這是我的代碼，當我運行它時，它正確下載文件，但可能會在pc中使用很多內存。例如：我的內存是2.02 GB，當我運行應用程序時，我的內存達到了3GB，並減慢了我的電腦。 我使用wampserver爲我的網絡服務器和我的代碼，並設置http標題爲可能的對象，我donwnload文件正確，謝謝你的幫助。

private void downloadFile() { 
    try { 
     this.response = this.con.getInputStream(); 
     this.bis = new BufferedInputStream(this.response, 1024 * 1024); 
     //int responseCode = this.con.getResponseCode(); 
     this.responseContentSize = this.con.getContentLength(); 

     //check kon bebin meghadare bargashti content ba on range ke to behesh gofti mosavi hast ya kheir 
     if (this.responseContentSize == (this.end_range - this.start_range) + 1) { 
      //fpointer = new RandomAccessFile(this.filePath, "rw"); 
      //fpointer.seek(this.start_range); 
      byte buffer[] = new byte[MAX_BUFFER_SIZE]; 
      //out = new FileOutputStream(this.filePath); 
      makeTmpFile(); 
      out = new FileOutputStream(this.tmpdir + this.tmpFilename); 
      bos = new BufferedOutputStream(out, 1024 * 1024); 
      sharedDownloadStatus.setCell(this.threadIndex, STATUS, 1);//downloading 
      while (true) { 
       //int read = response.read(buffer, 0, this.MAX_BUFFER_SIZE); 
       int read = bis.read(buffer, 0, this.MAX_BUFFER_SIZE); 
       if (read == -1) 
        break; 
       //out.write(buffer, 0, read); 
       //fpointer.write(buffer, 0, read); 
       bos.write(buffer, 0, read); 
       downloadedBytes += read; 
       sharedDownloadStatus.setCell(this.threadIndex, DOWNLOADED, downloadedBytes); 
      } 

      if (bos != null) 
       bos.close(); 
      if (out != null) 
       out.close(); 
      if (fpointer != null) 
       fpointer.close(); 
      if (bis != null) 
       bis.close(); 
      if (response != null) 
       response.close(); 
      sharedDownloadStatus.setCell(this.threadIndex, STATUS, 2);//finish 
     } 
    } catch (IOException e) { 
     sharedDownloadStatus.setCell(this.threadIndex, STATUS, 0);//error 
     log.setLog("func : downloadFile =>\n couldnt download file\n" + e.getMessage()); 
    } 

} 

Answer 1

你不需要兆字節緩衝區，但主要的問題是，除非一個固定長度或分塊傳輸模式有效，這是由服務器，而不是客戶端進行控制HttpURLConnection的將緩存一切。