使用post的方式发送http请求

/**

* 使用post的方式发送http请求  

* @param uri  请求资源路径

* @param params  请求参数

* @return

* @throws MalformedURLException 

*/

public static InputStream postInputStream(String uri, Map<String, String> params) throws IOException{

URL url = new URL(uri);

HttpURLConnection conn=(HttpURLConnection) url.openConnection();

conn.setRequestMethod("POST");

conn.setDoInput(true);

conn.setDoOutput(true);

conn.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");

//设置参数

StringBuilder param=new StringBuilder();

Set<String> keySet = params.keySet();

Iterator<String> ite = keySet.iterator();

while(ite.hasNext()){

String key=ite.next();

String val=params.get(key);

param.append(key+"="+val+"&");

}

//param:    a=b&c=d&

param.deleteCharAt(param.length()-1);

//传递参数

OutputStream os = conn.getOutputStream();

os.write(param.toString().getBytes("utf-8"));

os.flush();

//获取输入流

return conn.getInputStream();

}