java实现http,post请求

import org.apache.http.HttpEntity;
import org.apache.http.NameValuePair;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.util.EntityUtils;

import com.alibaba.fastjson.JSONObject;


public class testUtil {


	public static void main(String[] args) {
        /**
         *请求
         */
	    String url = "https://ccdcapi.alipay.com/validateAndCacheCardInfo.json";
	    Map map = new HashMap();
	    map.put("cardNo", "6221506020009066385");
	    map.put("cardBinCheck", "true");
        String json_Str = send(url, map, "utf-8");
        JSONObject json_obj= JSONObject.parseObject(json_Str);
        System.out.println(json_obj.get("bank")+"");
    }


    /**
	 * 请求
	 * 
	 * @param url
	 *            资源地址
	 * @param map
	 *            参数列表
	 * @param encoding
	 *            编码
	 * @return
	 * @throws IOException
	 */
	public static String send(String url, Map map, String encoding) throws Exception {
		String body = "";

		// 创建httpclient对象
		CloseableHttpClient client = HttpClients.createDefault();
		// 创建post方式请求对象
		HttpPost httpPost = new HttpPost(url);

		// 装填参数
		List nvps = new ArrayList();
		if (map != null) {
			for (Entry entry : map.entrySet()) {
				nvps.add(new BasicNameValuePair(entry.getKey(), entry.getValue()));
			}
		}
		// 设置参数到请求对象中
		httpPost.setEntity(new UrlEncodedFormEntity(nvps, encoding));

		// 设置header信息
		// 指定报文头【Content-type】、【User-Agent】
		httpPost.setHeader("Content-type", "application/x-www-form-urlencoded");

		// 执行请求操作，并拿到结果（同步阻塞）
		CloseableHttpResponse response = client.execute(httpPost);
		// 获取结果实体
		HttpEntity entity = response.getEntity();
		if (entity != null) {
			// 按指定编码转换结果实体为String类型
			body = EntityUtils.toString(entity, encoding);
		}
		EntityUtils.consume(entity);
		// 释放链接
		response.close();
		return body;
	}
}