HttpClient4.3.1 HttpPost .

1、先看一下示例代码

public class HttpClientTest {
    public static void main(String args[]) {
        //创建HttpClientBuilder
        HttpClientBuilder httpClientBuilder = HttpClientBuilder.create();
        //HttpClient
        CloseableHttpClient closeableHttpClient = httpClientBuilder.build();

        HttpGet httpGet = new HttpGet("http://www.gxnu.edu.cn/default.html");
        System.out.println(httpGet.getRequestLine());
        try {
            //执行get请求
            HttpResponse httpResponse = closeableHttpClient.execute(httpGet);
            //获取响应消息实体
            HttpEntity entity = httpResponse.getEntity();
            //响应状态
            System.out.println("status:" + httpResponse.getStatusLine());
            //判断响应实体是否为空
            if (entity != null) {
                System.out.println("contentEncoding:" + entity.getContentEncoding());
                System.out.println("response content:" + EntityUtils.toString(entity));
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            t

                //关闭流并释放资源
                closeableHttpClient.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}

2、HttpClientBuilder

HttpClientBuilder用于创建CloseableHttpClient实例。看了一下API文档，AbstractHttpClient、 AutoRetryHttpClient、 DefaultHttpClient等都被弃用了，使用HttpClientBuilder代替。

3、CloseableHttpClient

实现接口：Closeable, AutoCloseable, HttpClient；子类：AbstractHttpClient

4、HttpGet

非线程安全；HttpGet有三个构造方法：HttpGet()、HttpGet(String uri)、HttpGet(URI uri)

5、HttpResponse

服务器在接收和解释请求之后返回一个HTTP响应信息

 public static void main(String args[]) {
        //创建HttpClientBuilder
        HttpClientBuilder httpClientBuilder = HttpClientBuilder.create();
        //HttpClient
        CloseableHttpClient closeableHttpClient = httpClientBuilder.build();

        HttpPost httpPost = new HttpPost("http://tutor.sturgeon.mopaas.com/tutor/search");
        httpPost.setConfig(DEFAULT);
        // 创建参数队列
        List<NameValuePair> formparams = new ArrayList<NameValuePair>();
        formparams.add(new BasicNameValuePair("searchText", "英语"));

        UrlEncodedFormEntity entity;
        try {
            entity = new UrlEncodedFormEntity(formparams, "UTF-8");
            httpPost.setEntity(entity);

            HttpResponse httpResponse;
            //post请求
            httpResponse = closeableHttpClient.execute(httpPost);

            //getEntity()
            HttpEntity httpEntity = httpResponse.getEntity();
            if (httpEntity != null) {
                //打印响应内容
                System.out.println("response:" + EntityUtils.toString(httpEntity, "UTF-8"));
            }
            //释放资源
            closeableHttpClient.close();
        } catch (Exception e) {
            e.printStackTrace();
        }

    }