HttpClient简述

HttpClient相比传统JDK自带的URLConnection，增加了易用性和灵活性，它不仅是客户端发送Http请求变得容易，而且也方便了开发人员测试接口（基于Http协议的），即提高了开发的效率，也方便提高代码的健壮性。示例：发送Post/Get请求接口。

依赖包

<dependency>

<groupId>org.apache.httpcomponents</groupId>

<artifactId>httpclient</artifactId>

<version>4.3.6</version>

</dependency>

<dependency>

<groupId>org.apache.httpcomponents</groupId>

<artifactId>httpclient-cache</artifactId>

<version>4.3.6</version>

</dependency>

<dependency>

<groupId>org.apache.httpcomponents</groupId>

<artifactId>httpmime</artifactId>

<version>4.3.6</version>

</dependency>

代码示例：

HttpClient连接池

/**

* http连接池

* Created by liujia68 on 2018/11/15

*/

public class HttpClientUtils {

private static PoolingHttpClientConnectionManager connectionManager;//连接池管理类

private static HttpClientBuilder httpBuilder;

static RequestConfig requestConfig;

private static int MAXCONNECTION = 10;

private static int DEFAULTMAXCONNECTION = 5;

//static String IP = "cnivi.com.cn";

//private static int PORT = 80;

static String IP = "172.28.91.145";

private static int PORT = 8080;

static {

//设置http的状态参数

requestConfig = RequestConfig.custom()

.setConnectTimeout(5000)//一、连接超时：connectionTimeout-->指的是连接一个url的连接等待时间

.setSocketTimeout(5000)// 二、读取数据超时：SocketTimeout-->指的是连接上一个url，获取response的返回等待时间

.setConnectionRequestTimeout(5000)//三、从连接池获取连接的超时，如果连接池里连接都被用了，且超过这个时间，会抛出超时异常

.build();

HttpHost target = new HttpHost(IP, PORT);

connectionManager = new PoolingHttpClientConnectionManager();

connectionManager.setMaxTotal(MAXCONNECTION);//客户端总并行链接最大数

connectionManager.setDefaultMaxPerRoute(DEFAULTMAXCONNECTION);//每个主机的最大并行链接数

connectionManager.setMaxPerRoute(new HttpRoute(target), 20);///设置到每个路由的最大连接数

httpBuilder = HttpClients.custom();

httpBuilder.setConnectionManager(connectionManager);

}

static CloseableHttpClient getConnection() {

CloseableHttpClient httpClient = httpBuilder.build();

return httpClient;

}

static void dealResult(CloseableHttpResponse response) {

if (response.getStatusLine().getStatusCode() == 200) {

HttpEntity entity = response.getEntity();

String message = null;

try {

message = EntityUtils.toString(entity, "utf-8");

} catch (IOException e) {

e.printStackTrace();

}

System.out.println(message);

} else {

System.out.println("请求失败");

}

}

}

测试类

public class test {

private static void testPost() throws Exception{

CloseableHttpClient client = getConnection();

//URL+入参requestParam

URIBuilder uriBuilder = new URIBuilder("http://www.sogou.com/web");

uriBuilder.addParameter("query","花千骨");

//requestBody

List<NameValuePair> formparams = new ArrayList<NameValuePair>();

formparams.add(new BasicNameValuePair("account", ""));

formparams.add(new BasicNameValuePair("password", ""));

HttpEntity reqEntity = new UrlEncodedFormEntity(formparams, "utf-8");

HttpPost post = new HttpPost(uriBuilder.build());//URL+入参requestParam

post.setEntity(reqEntity); //requestBody

post.setConfig(requestConfig);

CloseableHttpResponse response = client.execute(post);

dealResult(response);

response.close();

client.close();

}

private static void testGet(){

try (CloseableHttpClient httpClient = getConnection()){

//URL+入参requestParam

URIBuilder uriBuilder = new URIBuilder("http://172.28.91.145:8080/bp-query-service");

uriBuilder.addParameter("sid","gx");

uriBuilder.addParameter("curTime","20181115");

uriBuilder.addParameter("queryType","TUV");

uriBuilder.addParameter("dataRule","byTotal");

uriBuilder.addParameter("appid","1");

uriBuilder.addParameter("clientid","1");

uriBuilder.addParameter("conditionTabs","");

HttpGet httpget = new HttpGet(uriBuilder.build());//URL+入参requestParam

httpget.setConfig(requestConfig);

CloseableHttpResponse response = httpClient.execute(httpget);

dealResult(response);

response.close();

} catch (ClientProtocolException e) {

e.printStackTrace();

} catch (URISyntaxException e) {

e.printStackTrace();

} catch (IOException e) {

e.printStackTrace();

}

}

}