java https 连接池_httpclient连接池，解决后台高并发的请求

在后台发送http请求时，每次都要经过三次握手的过程，这是一个比较耗时的操作且稳定性不好，经常连接失败。所以采用httpclient连接池，发起请求时直接从池里面获取连接，不用每次发起请求都经过三次握手，大大的提高的并发的效率

1.maven依赖

org.apache.httpcomponents

httpclient

4.5.2

com.alibaba

fastjson

1.2.3

2.http请求工具类

package com.litice.core.util;

import org.apache.http.HttpStatus;

import org.apache.http.client.config.RequestConfig;

import org.apache.http.client.methods.CloseableHttpResponse;

import org.apache.http.client.methods.HttpGet;

import org.apache.http.config.Registry;

import org.apache.http.config.RegistryBuilder;

import org.apache.http.conn.socket.ConnectionSocketFactory;

import org.apache.http.conn.socket.LayeredConnectionSocketFactory;

import org.apache.http.conn.socket.PlainConnectionSocketFactory;

import org.apache.http.conn.ssl.SSLConnectionSocketFactory;

import org.apache.http.impl.client.CloseableHttpClient;

import org.apache.http.impl.client.HttpClients;

import org.apache.http.impl.conn.PoolingHttpClientConnectionManager;

import org.apache.http.util.EntityUtils;

import org.slf4j.Logger;

import org.slf4j.LoggerFactory;

import com.alibaba.fastjson.JSONObject;

import java.io.IOException;

import java.net.URLDecoder;

import java.security.NoSuchAlgorithmException;

import javax.net.ssl.SSLContext;

public class HttpJsonUtil {

private static Logger logger = LoggerFactory.getLogger(HttpJsonUtil.class);

// 默认超时时间：10s

private static final int TIME_OUT = 10 * 1000;

private static PoolingHttpClientConnectionManager cm = null;

static{

LayeredConnectionSocketFactory sslsf = null;

try{

sslsf = new SSLConnectionSocketFactory(SSLContext.getDefault());

}catch(NoSuchAlgorithmException e){

logger.error("创建SSL连接失败...");

}

Registry sRegistry = RegistryBuilder.create()

.register("https", sslsf)

.register("http", new PlainConnectionSocketFactory())

.build();

cm = new PoolingHttpClientConnectionManager(sRegistry);

// 设置最大的连接数

cm.setMaxTotal(200);

// 设置每个路由的基础连接数【默认，每个路由基础上的连接不超过2个，总连接数不能超过20】

cm.setDefaultMaxPerRoute(20);

}

private static CloseableHttpClient getHttpClient(){

CloseableHttpClient httpClient = HttpClients.custom()

.setConnectionManager(cm).build();

return httpClient;

}

public static JSONObject httpGet(String url) {

JSONObject jsonResult = null;

CloseableHttpClient httpClient = getHttpClient();

// get请求返回结果

CloseableHttpResponse response = null;

try {

// 配置请求超时时间

RequestConfig requestConfig = RequestConfig.custom()

.setConnectTimeout(TIME_OUT).setConnectionRequestTimeout(TIME_OUT)

.setSocketTimeout(TIME_OUT).build();

// 发送get请求

HttpGet request = new HttpGet(url);

request.setConfig(requestConfig);

response = httpClient.execute(request);

// 请求发送成功，并得到响应

if (response.getStatusLine().getStatusCode() == HttpStatus.SC_OK) {

// 读取服务器返回过来的json字符串数据

String strResult = EntityUtils.toString(response.getEntity());

// 把json字符串转换成json对象

jsonResult = JSONObject.parseObject(strResult);

url = URLDecoder.decode(url, "UTF-8");

} else {

logger.error("get请求提交失败:" + url);

}

} catch (IOException e) {

logger.error("get请求提交失败:" + url, e);

} finally {

if( response != null){

try {

EntityUtils.consume(response.getEntity());

response.close();

} catch (IOException e) {

logger.error("关闭response失败:", e);

}

}

}

return jsonResult;

}

}

```