/**
 * @author why
 *
 */
public class VoiceDownload {
	/**
	 * 
	 * 根据文件id下载文件
	 * 
	 * 
	 * 
	 * @param mediaId
	 * 
	 *            媒体id
	 * 
	 * @throws Exception
	 */

	public static InputStream getInputStream(String accessToken, String mediaId) {
		InputStream is = null;
		String url = "http://file.api.weixin.qq.com/cgi-bin/media/get?access_token="
				+ accessToken + "&media_id=" + mediaId;
		try {
			URL urlGet = new URL(url);
			HttpURLConnection http = (HttpURLConnection) urlGet
					.openConnection();
			http.setRequestMethod("GET"); // 必须是get方式请求
			http.setRequestProperty("Content-Type",
					"application/x-www-form-urlencoded");
			http.setDoOutput(true);
			http.setDoInput(true);
			System.setProperty("sun.net.client.defaultConnectTimeout", "30000");// 连接超时30秒
			System.setProperty("sun.net.client.defaultReadTimeout", "30000"); // 读取超时30秒
			http.connect();
			// 获取文件转化为byte流
			is = http.getInputStream();

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

	}

	/**
	 * 
	 * 获取下载图片信息（jpg）
	 * 
	 * 
	 * 
	 * @param mediaId
	 * 
	 *            文件的id
	 * 
	 * @throws Exception
	 */

	public static void saveImageToDisk(String accessToken, String mediaId, String picName, String picPath)
			throws Exception {
		InputStream inputStream = getInputStream(accessToken, mediaId);
		byte[] data = new byte[10240];
		int len = 0;
		FileOutputStream fileOutputStream = null;
		try {
			fileOutputStream = new FileOutputStream(picPath+picName+".amr");
			while ((len = inputStream.read(data)) != -1) {
				fileOutputStream.write(data, 0, len);
			}
		} catch (IOException e) {
			e.printStackTrace();
		} finally {
			if (inputStream != null) {
				try {
					inputStream.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			if (fileOutputStream != null) {
				try {
					fileOutputStream.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
		}
	}

}

java 微信服务器录音下载到自己服务器