maven
<!-- https://mvnrepository.com/artifact/org.apache.httpcomponents/httpclient -->
<dependency>
<groupId>org.apache.httpcomponents</groupId>
<artifactId>httpclient</artifactId>
<version>4.5.6</version>
</dependency>import org.apache.http.*;
import org.apache.http.client.HttpRequestRetryHandler;
import org.apache.http.client.config.RequestConfig;
import org.apache.http.client.protocol.HttpClientContext;
import org.apache.http.config.*;
import org.apache.http.conn.ConnectTimeoutException;
import org.apache.http.conn.routing.HttpRoute;
import org.apache.http.conn.socket.ConnectionSocketFactory;
import org.apache.http.conn.socket.PlainConnectionSocketFactory;
import org.apache.http.conn.ssl.SSLConnectionSocketFactory;
import org.apache.http.conn.ssl.TrustSelfSignedStrategy;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.DefaultHttpRequestRetryHandler;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.impl.conn.PoolingHttpClientConnectionManager;
import org.apache.http.protocol.HttpContext;
import org.apache.http.ssl.SSLContexts;
import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLException;
import javax.net.ssl.SSLHandshakeException;
import java.io.IOException;
import java.io.InterruptedIOException;
import java.net.UnknownHostException;
import java.nio.charset.CodingErrorAction;
/**
* @description：<br>
* @author: caiyaming
* @date: 2018-07-31 10:07
* @since: V1.0.0
*/
public class HttpUtils {
private static PoolingHttpClientConnectionManager clientConnectionManager = null;
private static CloseableHttpClient httpClient = null;
//private static RequestConfig config = RequestConfig.custom().setCookieSpec(CookieSpecs.STANDARD_STRICT).build();
private static RequestConfig config = null;
private static HttpRequestRetryHandler httpRequestRetryHandler = null;
/**
* 双检锁/双重校验锁, 防止httpClient实例多次
*/
public static CloseableHttpClient getHttpClient() {
if (httpClient == null) {
synchronized (HttpUtils.class) {
if (httpClient == null) {
init();
httpClient = HttpClients.custom()
.setConnectionManager(clientConnectionManager) //连接管理器
//.setProxy(new HttpHost("myproxy", 8080)) //设置代理
.setDefaultRequestConfig(config) //默认请求配置
.setRetryHandler(httpRequestRetryHandler) //重试策略
.build();
}
}
}
return httpClient;
}
/**
* 创建httpclient连接池并初始化
*/
private static void init() {
try {
//添加对https的支持，该sslContext没有加载客户端证书
// 如果需要加载客户端证书，请使用如下sslContext,其中KEYSTORE_FILE和KEYSTORE_PASSWORD分别是你的证书路径和证书密码
//KeyStore keyStore = KeyStore.getInstance(KeyStore.getDefaultType()
//FileInputStream instream = new FileInputStream(new File(KEYSTORE_FILE));
//keyStore.load(instream, KEYSTORE_PASSWORD.toCharArray());
//SSLContext sslContext = SSLContexts.custom().loadKeyMaterial(keyStore,KEYSTORE_PASSWORD.toCharArray())
// .loadTrustMaterial(null, new TrustSelfSignedStrategy())
//.build();
//这里设置信任所有证书
SSLContext sslContext = SSLContexts.custom().loadTrustMaterial(null, new TrustStrategy() {
// 信任所有
public boolean isTrusted(X509Certificate[] chain, String authType) throws CertificateException {
return true;
}
}).build();
SSLConnectionSocketFactory sslsf = new SSLConnectionSocketFactory(sslContext, NoopHostnameVerifier.INSTANCE);
Registry<ConnectionSocketFactory> socketFactoryRegistry = RegistryBuilder.<ConnectionSocketFactory>create()
.register("https", sslsf)
.register("http", PlainConnectionSocketFactory.getSocketFactory())
.build();
//配置连接池
clientConnectionManager = new PoolingHttpClientConnectionManager(socketFactoryRegistry);
//最大连接
clientConnectionManager.setMaxTotal(50);
//默认的每个路由的最大连接数
clientConnectionManager.setDefaultMaxPerRoute(25);
//设置到某个路由的最大连接数，会覆盖defaultMaxPerRoute
clientConnectionManager.setMaxPerRoute(new HttpRoute(new HttpHost("127.0.0.1", 80)), 150);
/**
* socket配置（默认配置 和 某个host的配置）
*/
SocketConfig socketConfig = SocketConfig.custom()
.setTcpNoDelay(true) //是否立即发送数据，设置为true会关闭Socket缓冲，默认为false
.setSoReuseAddress(true) //是否可以在一个进程关闭Socket后，即使它还没有释放端口，其它进程还可以立即重用端口
.setSoTimeout(500) //接收数据的等待超时时间，单位ms
.setSoLinger(6) //关闭Socket时，要么发送完所有数据，要么等待60s后，就关闭连接，此时socket.close()是阻塞的
.setSoKeepAlive(true) //开启监视TCP连接是否有效
.build();
clientConnectionManager.setDefaultSocketConfig(socketConfig);
clientConnectionManager.setSocketConfig(new HttpHost("somehost", 80), socketConfig);
/**
* HTTP connection相关配置（默认配置 和 某个host的配置）
* 一般不修改HTTP connection相关配置，故不设置
*/
//消息约束
MessageConstraints messageConstraints = MessageConstraints.custom()
.setMaxHeaderCount(200)
.setMaxLineLength(2000)
.build();
//Http connection相关配置
ConnectionConfig connectionConfig = ConnectionConfig.custom()
.setMalformedInputAction(CodingErrorAction.IGNORE)
.setUnmappableInputAction(CodingErrorAction.IGNORE)
.setCharset(Consts.UTF_8)
.setMessageConstraints(messageConstraints)
.build();
//一般不修改HTTP connection相关配置，故不设置
//connManager.setDefaultConnectionConfig(connectionConfig);
//connManager.setConnectionConfig(new HttpHost("somehost", 80), ConnectionConfig.DEFAULT);
// 配置请求的超时设置
config = RequestConfig.custom()
.setConnectTimeout(2 * 1000) //连接超时时间
.setSocketTimeout(2 * 1000) //读超时时间（等待数据超时时间）
.setConnectionRequestTimeout(500) //从池中获取连接超时时间
.setStaleConnectionCheckEnabled(true)//检查是否为陈旧的连接，默认为true，类似testOnBorrow
.build();
/**
* 重试处理
* 默认是重试3次
*/
//禁用重试(参数：retryCount、requestSentRetryEnabled)
HttpRequestRetryHandler requestRetryHandler = new DefaultHttpRequestRetryHandler(0, false);
//自定义重试策略
httpRequestRetryHandler = new HttpRequestRetryHandler() {
public boolean retryRequest(IOException exception,
int executionCount, HttpContext context) {
if (executionCount >= 3) {// 如果已经重试了3次，就放弃
return false;
}
if (exception instanceof NoHttpResponseException) {// 如果服务器丢掉了连接，那么就重试
return true;
}
if (exception instanceof SSLHandshakeException) {// 不要重试SSL握手异常
return false;
}
if (exception instanceof InterruptedIOException) {// 超时
return false;
}
if (exception instanceof UnknownHostException) {// 目标服务器不可达
return false;
}
if (exception instanceof ConnectTimeoutException) {// 连接被拒绝
return false;
}
if (exception instanceof SSLException) {// SSL握手异常
return false;
}
HttpClientContext clientContext = HttpClientContext
.adapt(context);
HttpRequest request = clientContext.getRequest();
//Retry if the request is considered idempotent
//如果请求类型不是HttpEntityEnclosingRequest，被认为是幂等的，那么就重试
//HttpEntityEnclosingRequest指的是有请求体的request，比HttpRequest多一个Entity属性
//而常用的GET请求是没有请求体的，POST、PUT都是有请求体的
//Rest一般用GET请求获取数据，故幂等，POST用于新增数据，故不幂等
if (!(request instanceof HttpEntityEnclosingRequest)) {
return true;
}
return false;
}
};
} catch (Exception e) {
e.printStackTrace();
}
}
}