java发起http请求调用post与get接口的方法实例

public static String sendPost(String url, String param) {
        OutputStreamWriter out = null;
        BufferedReader in = null;
        StringBuilder result = new StringBuilder("");
        try {
            URL realUrl = new URL(url);
            // 打开和URL之间的连接
            URLConnection conn = realUrl.openConnection();
            // 设置通用的请求属性
            conn.setRequestProperty("Content-Type","application/JSON;charset=UTF-8");
            conn.setRequestProperty("accept", "**");
        connection.setRequestProperty("connection", "Keep-Alive");
        connection.setRequestProperty("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; windows NT 5.1;SV1)");
        // 建立实际的连接
        connection.connect();
        // 获取所有响应头字段
        // 定义 BufferedReader输入流来读取URL的响应
        in = new BufferedReader(new InputStreamReader(connection.getInputStream(),"UTF-8"));
        String line;
        while ((line = in.readLine()) != null) {
            result.append(line);
        }
    } catch (Exception e) {
        System.out.println("发送GET请求出现异常！" + e);
        e.printStackTrace();
    }
    finally {
    	if (in != null){ try { in.close(); }catch(Exception e2){} }
    }
    return result.toString();
}