如何用java发送Http的post请求，并传递参数

package utils;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.net.URL;
import java.net.URLConnection;

public class TestClass {
public static void main(String[] args) {
OutputStreamWriter out = null ;
BufferedReader in = null;
StringBuilder result = new StringBuilder();
String url = "http://192.168.0.104:8088/songsController/selectTotalList";
String sign = "11f5c83b448383cdb34330d5ddc88209";
try {
URL realUrl = new URL(url);
// 打开和URL之间的连接
URLConnection conn = realUrl.openConnection();
//设置通用的请求头属性
conn.setRequestProperty("accept", "*/*");
conn.setRequestProperty("connection", "Keep-Alive");
conn.setRequestProperty("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");
// 发送POST请求必须设置如下两行 否则会抛异常（java.net.ProtocolException: cannot write to a URLConnection if doOutput=false - call setDoOutput(true)）
conn.setDoOutput(true);
conn.setDoInput(true);
//获取URLConnection对象对应的输出流并开始发送参数
out = new OutputStreamWriter(conn.getOutputStream(), "UTF-8");
//添加参数
out.write("&songid="+"10800537");
out.flush();
in = new BufferedReader(new InputStreamReader(conn.getInputStream(),"UTF-8"));
String line;
while ((line = in.readLine()) != null) {
result.append(line);
}
} catch (Exception e) {
e.printStackTrace();
}finally {// 使用finally块来关闭输出流、输入流
try {
if (out != null) {
out.close();
}
if (in != null) {
in.close();
}
} catch (IOException ex) {
ex.printStackTrace();
}
}
System.out.println(result.toString());
}

}