HttpClient 4.3与4.3版本以下版本比较

网上利用java发送http请求的代码很多，一搜一大把，有的利用的是java.net.*下的HttpURLConnection，有的用httpclient，而且发送的代码也分门别类。今天我们主要来说的是利用httpclient发送请求。

httpclient又可分为

• httpclient3.x
• httpclient4.x到httpclient4.3以下
• httpclient4.3以上

不同httpclient版本其请求发送的方式也不一样，下面来做个归纳

 

httpclient3.x

		HttpClient client = new HttpClient();
		// 设置代理服务器地址和端口
		// client.getHostConfiguration().setProxy("proxy_host_addr",proxy_port);
		// 使用 GET 方法 ，如果服务器需要通过 HTTPS 连接，那只需要将下面 URL 中的 http 换成 https
		HttpMethodmethod = new GetMethod("http://java.sun.com");
		// 使用POST方法
		// HttpMethod method = new PostMethod("http://java.sun.com");
		client.executeMethod(method);
		// 打印服务器返回的状态
		System.out.println(method.getStatusLine());
		// 打印返回的信息
		System.out.println(method.getResponseBodyAsString());
		// 释放连接
		method.releaseConnection();

 

 

httpclient4.x到httpclient4.3以下

 

public void getUrl(String url, String encoding) throws ClientProtocolException, IOException {
		HttpClient client = new DefaultHttpClient();
		HttpGet get = new HttpGet(url);
		HttpResponse response = client.execute(get);
		HttpEntity entity = response.getEntity();
		if (entity != null) {
			InputStream instream = entity.getContent();
			try {
				BufferedReader reader = new BufferedReader(new InputStreamReader(instream, encoding));
				System.out.println(reader.readLine());
			} catch (Exception e) {
				e.printStackTrace();
			} finally {
				instream.close();
			}
		}
		// 关闭连接.
		client.getConnectionManager().shutdown();
	}

 

 

 

httpclient4.3以上

 

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;


public static String getResult(String urlStr) {
		CloseableHttpClient httpClient = HttpClients.createDefault();
		// HTTP Get请求
		HttpGet httpGet = new HttpGet(urlStr);
		// 设置请求和传输超时时间
		// RequestConfig requestConfig =
		// RequestConfig.custom().setSocketTimeout(TIME_OUT).setConnectTimeout(TIME_OUT).build();
		// httpGet.setConfig(requestConfig);
		String res = "";
		try {
			// 执行请求
			HttpResponse getAddrResp = httpClient.execute(httpGet);
			HttpEntity entity = getAddrResp.getEntity();
			if (entity != null) {
				res = EntityUtils.toString(entity);
			}
			log.info("响应" + getAddrResp.getStatusLine());
		} catch (Exception e) {
			log.error(e.getMessage(), e);
			return res;
		} finally {
			try {
				httpClient.close();
			} catch (IOException e) {
				log.error(e.getMessage(), e);
				return res;
			}
		}
		return res;
	}