用java的.net包和http的post实现upload和download- -

最新推荐文章于 2025-05-12 17:30:24 发布

smallfish6

最新推荐文章于 2025-05-12 17:30:24 发布

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文章标签： upload .net java exception url null

用java的.net包和http的post实现upload和download- -

　　用java的.net包和http的post实现upload和download。需要用到的对象有URL, HttpURLConnection, OutputStreamWriter等．下面给出源码：

1.文件上传：


	HttpURLConnection conn = null;
	BufferedWriter bWriter = null;
	OutputStream os = null;
	OutputStreamWriter osw = null;
	String strData = "filename=postest.txt&data=1234566778888";
	
	try {
		URL url1 = new URL("http://yoururl/upload.php");
		conn = (HttpURLConnection)url1.openConnection();
		conn.setRequestMethod("POST");
		conn.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
		conn.setRequestProperty("Connection", "Keep-Alive");
		conn.setUseCaches( false);
		conn.setDoOutput(true);
		osw = new OutputStreamWriter(conn.getOutputStream());
		osw.write("filename=postest.txt&data=1234567890");
		osw.flush() ;
		osw.close() ;
		
		if (conn.getResponseCode() != HttpURLConnection.HTTP_OK)
			System.out.println( "connect failed!");
	}
	catch (Exception e) {
		e.printStackTrace(System.out);
	}
	finally
	{
		if (osw != null)
			try {
				osw.close() ;
			} catch (IOException e1) {
				e1.printStackTrace(System.out);
			}
		
		if (conn != null)
			conn.disconnect() ;
	}

	php根据上传数据写文件的代码（一些额外的代码都被去掉了）：
	if($data!="")
	{	
		$path="filepath/".trim($filename);
		$fp = fopen($path,"a");
		if($fp)
		{
			flock($fp,2);
			$fw=fputs($fp,$data);
			fclose($fp);
			Header("Location: http://yourhost/succes.php");
		}
		else
		{
			Header("Location: http://yourhost/error.php");
		}
	}
	else
	{
		Header("Location: http://yourhost/error.php");
	}

2.文件下载：


	HttpURLConnection conn = null;
	RandomAccessFile f=null;
	InputStream is = null;
	int contentlength = 0;
	int spos = 0;
	int epos = 0;
	int nread = 0;
	
	try
	{
		URL url1 = new URL("yoururl/download.rar");
		conn = (HttpURLConnection)url1.openConnection();
		conn.setRequestMethod("GET");
		conn.setRequestProperty("User-Agent", "NetFox");
		conn.setRequestProperty("Connection", "Keep-Alive");
		
		for (int i=1;; i++)
		{
			String head = conn.getHeaderFieldKey(i);
			if (head == null)
				break;
			
			System.out.println(head+": "+ conn.getHeaderField(head));
		}
		
		epos = contentlength = conn.getContentLength() ;
		is = conn.getInputStream();
		int unitsize = contentlength<1024?contentlength:1024;
		byte[] b = new byte[unitsize];
		f = new RandomAccessFile("C:/eclipse/workspace/pgtest/download/posttest.rar", "rw");
		
		System.out.println("Receive data beginning:");
		while ((nread=is.read(b, 0, unitsize))>0 && spos小于epos)
		{
			f.write(b);
			spos += unitsize;
			System.out.println("has received bytes:" + spos);
		}
	}
	catch (FileNotFoundException fnfe)
	{
		System.out.println("file " + f.toString() + " is not found.");
	} catch (Exception e) {
		e.printStackTrace(System.out);
	}
	finally
	{
		if (f != null)
			try {
				f.close() ;
			} catch (IOException e1) {
				e1.printStackTrace(System.out);
			}
			
		if (is != null)
			try {
				is.close();
			} catch (IOException ioe) {
				ioe.printStackTrace(System.out);
			}
				
		if (conn != null)
			conn.disconnect() ;
	}
	
	System.out.println("download success!");

From:

http://jimjava.bokee.com/414949.html