httpclient4

首先你需要下载httpclient4的jar包,搜索httpclient去apache官网下载吧



//demo1: post

/**
 * HttpClient4之post请求,json格式
 * 
 * @param strURL
 *            服务地址
 * @param params
 *            json字符串,例如: "{ \"id\":\"12345\" }" 其中属性名必须带双引号
 */
public static String post(String url, String params) {
	DefaultHttpClient httpclient = new DefaultHttpClient();
	try {
		HttpPost httppost = new HttpPost(url);
		StringEntity s = new StringEntity(params);
		s.setContentEncoding("UTF-8");
		s.setContentType("application/json");
		// 设置请求的数据
		httppost.setEntity(s);
		// 执行
		HttpResponse response = httpclient.execute(httppost);
		// 状态
		StatusLine status = response.getStatusLine();
		System.out.println(status.getStatusCode());// 200:成功

		HttpEntity entity = response.getEntity();
		if (entity != null) {
			// 长度
			long length = entity.getContentLength();
			System.out.println("Response content length: " + length);
			// 结果
			BufferedReader reader = new BufferedReader(
					new InputStreamReader(entity.getContent(), "UTF-8"));
			String result = "";
			String line = null;
			while ((line = reader.readLine()) != null) {
				result += line;
			}
			System.out.println(result);
			return result;
		}
	} catch (Exception e) {
		e.printStackTrace();
	}
	return null;
}