java基础——用HttpURLConnection向服务器发送POST请求

OutputStream out = null;
InputStream in = null;
OutputStreamWriter outWrite = null;
InputStreamReader inReader = null;
BufferedReader  buffReader = null;
String line = "";
StringBuffer buff = new StringBuffer();
//请求参数
String date="username=admin&password=123456";
URL url= new URL("http://localhost:7001/XXXX/test.action");
HttpURLConnection conn = (HttpURLConnection)url.openConnection(url);
//post请求
conn.setsetRequestMethod("POST");
//连接超时、读取超时。防止请求被阻塞
conn.setConnectTimeout(3000);
conn.setReadTimeout(3000);
//是否从httpUrlConnection读入，默认为false，当为post请求时需要设置为true
//post的请求参数在http正文中，get的请求参数在url后
conn.setDoOutput(true);
//是否向httpUrlConnection输出，默认为true
conn.setDoInput(true);
//设置请求头属性，用setRequestProperty方法时，key唯一，key相同时会覆盖
//用addRequestProperty方法时，value存在多个
conn.setRequestProperty("Content-Type","application/x-www-form-urlencoded");
//缓存
conn.setUseCaches(false);
try{
out = conn.getOutputStream();
outWrite = new OutputStreamWriter(out, "UTF-8");
outWrite.write(date);
outWrite.flush();
in = conn.getInputStream();
inReader = new InputStreamReader(in);
buffReader =  new BufferedReader(inReader);
while((line = buffReader.readLine())!= null){
buff.append(line);
}
}finally{
if(out!=null){
out.close();
}
if(in != null){
in.close();
}
if(conn != null){
conn.disconnect();
}
}