HttpClient MultipartRequestEntity文件上传，中文乱码解决方案

之前分享过HttpClient模拟登录第三方项目的代码，这次分享一下HttpClient访问第三方项目接口上传文件的实现方案，并解决中文乱码问题，并且在上传文件的时候传输多个其他参数；

第一种方案，中文参数在url内部，使用URLEncoder类对中文进行encode：

public static void postTwo() throws Exception{
		HttpClient client = new HttpClient();
		//登录
		PostMethod post = new PostMethod("http://127.0.0.1:8080/HelloWorld/post?host=172.16.2.183&port=10086&name=test&pw=test" + URLEncoder.encode("北京", "utf-8"));
		FilePart fp = new FilePart("formFile", new File("D://PTOC_SCENIC_DAY_2015043015.txt"));
		Part[] parts = {fp};
		
		MultipartRequestEntity entity = new MultipartRequestEntity(parts, new HttpMethodParams());
		post.setRequestEntity(entity);
		
		client.executeMethod(post);
		//释放连接，以免超过服务器负荷
		System.out.println("============================");
		System.out.println(post.getResponseBodyAsString());
		System.out.println("============================");
		//释放连接，以免超过服务器负荷
		post.releaseConnection();
	}

 第二种方案，使用Part类，该类有两个子类，一个StringPart，一个FilePart，StringPart用于传输普通字符串参数，FilePart用于上传文件：

public static void postThree() throws Exception{
		HttpClient client = new HttpClient();
		//登录
		PostMethod post = new PostMethod("http://127.0.0.1:8080/HelloWorld/post");
		FilePart fp = new FilePart("formFile", "JNDI.txt", new File("D://JNDI配置数据库连接池_获取数据库连接.txt"));
		fp.setCharSet("utf-8");
		System.out.println(fp.getCharSet());
		Part[] parts = { fp, new StringPart("host", "172.16.2.183", "UTF-8"),
				new StringPart("port", "10086", "UTF-8"),
				new StringPart("name", "test色鬼", "UTF-8"),
				new StringPart("pw", "test特殊", "UTF-8") };
		
		MultipartRequestEntity entity = new MultipartRequestEntity(parts, new HttpMethodParams());
		post.setRequestEntity(entity);
		System.out.println(entity.getContentType());
		
		client.executeMethod(post);
		//释放连接，以免超过服务器负荷
		System.out.println("============================");
		System.out.println(post.getResponseBodyAsString());
		System.out.println("============================");
		//释放连接，以免超过服务器负荷
		post.releaseConnection();
	}

 以上两种方案对应的第三方项目的接口代码如下：

@RequestMapping(value = "/post", method = { RequestMethod.POST })
	public @ResponseBody Map<String, Object> post(@RequestParam(value = "host") String host,
			@RequestParam("port") String port,
			@RequestParam("name") String name,
			@RequestParam("pw") String pw,
			@RequestParam("formFile") MultipartFile formFile) {
		Map<String, Object> map = new HashMap<String, Object>();
		try{
			map.put("tag", "1");
			map.put("msg", "上传成功!");
			System.out.println(host + ":" + port + " " + name + " " + pw);
			String fileName = formFile.getOriginalFilename();
			FileOutputStream write = new FileOutputStream("D://ww" + fileName);
			InputStream read = formFile.getInputStream();
			byte data[] = new byte[1024];
			int count;
			while ((count = read.read(data, 0, 1024)) != -1) {
				write.write(data, 0, count);
			}
			read.close();
			write.close();
		}catch (Exception e) {
			e.printStackTrace();
			map.put("tag", "0");
			map.put("msg", "上传失败:" + e.getMessage());
		}
		return map;
	}

这两只方案都只能解决普通字符串参数的中文乱码问题，对于上传的文件其文件名中文乱码问题不能使用setCharSet方法设置编码方式解决，至于原因，查看源码就可以知道，StringPart和FilePart类中对中午的处理方式不一样，FilePart在转换文件名时，用的方法是EncodingUtil.getAsciiBytes()，查看这个方法源码为data.getBytes("US-ASCII")，因此中文文件名必定乱码，不管你是否调用了setCharSet("GBK")方法。 解决很简单：out.write(EncodingUtil.getBytes(filename, getCharSet()));想要解决附件文件名中文乱码只能靠修改源码了，FilePart中对中午乱码起至关重要的部分为：

protected void sendDispositionHeader(OutputStream out) throws IOException {
		LOG.trace("enter sendDispositionHeader(OutputStream out)");
		super.sendDispositionHeader(out);
		String filename = this.source.getFileName();
		if (filename != null) {
			out.write(FILE_NAME_BYTES);
			out.write(QUOTE_BYTES);
			out.write(EncodingUtil.getAsciiBytes(filename));
			out.write(QUOTE_BYTES);
		}
	}