下面列出了org.apache.http.impl.io.DefaultHttpRequestWriterFactory#INSTANCE 实例代码，或者点击链接到github查看源代码，也可以在右侧发表评论。
public TracingManagedHttpClientConnectionFactory(final HttpMessageWriterFactory<HttpRequest> requestWriterFactory,
final HttpMessageParserFactory<HttpResponse> responseParserFactory, final ContentLengthStrategy incomingContentStrategy,
final ContentLengthStrategy outgoingContentStrategy, LogFunc logFunc) {
super();
this.requestWriterFactory = requestWriterFactory != null ? requestWriterFactory : DefaultHttpRequestWriterFactory.INSTANCE;
this.responseParserFactory = responseParserFactory != null ? responseParserFactory : DefaultHttpResponseParserFactory.INSTANCE;
this.incomingContentStrategy = incomingContentStrategy != null ? incomingContentStrategy : LaxContentLengthStrategy.INSTANCE;
this.outgoingContentStrategy = outgoingContentStrategy != null ? outgoingContentStrategy : StrictContentLengthStrategy.INSTANCE;
this.logFunc = logFunc != null ? logFunc : DefaultLogFunc.DEFAULT;
}
private CloseableHttpClient getHttpClient() {
//注册访问协议相关的Socket工厂
Registry<ConnectionSocketFactory> socketFactoryRegistry = RegistryBuilder.<ConnectionSocketFactory>create()
.register("http", PlainConnectionSocketFactory.INSTANCE)
.register("https", SSLConnectionSocketFactory.getSocketFactory())
.build();
//HttpConnectionFactory:配置写请求/解析响应处理器
HttpConnectionFactory<HttpRoute, ManagedHttpClientConnection> connectionFactory = new ManagedHttpClientConnectionFactory(
DefaultHttpRequestWriterFactory.INSTANCE,
DefaultHttpResponseParserFactory.INSTANCE
);
//DNS解析器
DnsResolver dnsResolver = SystemDefaultDnsResolver.INSTANCE;
//创建连接池管理器
PoolingHttpClientConnectionManager manager = new PoolingHttpClientConnectionManager(socketFactoryRegistry, connectionFactory, dnsResolver);
//设置默认的socket参数
manager.setDefaultSocketConfig(SocketConfig.custom().setTcpNoDelay(true).build());
manager.setMaxTotal(300);//设置最大连接数。高于这个值时，新连接请求，需要阻塞，排队等待
//路由是对MaxTotal的细分。
// 每个路由实际最大连接数默认值是由DefaultMaxPerRoute控制。
// MaxPerRoute设置的过小，无法支持大并发：ConnectionPoolTimeoutException:Timeout waiting for connection from pool
manager.setDefaultMaxPerRoute(200);//每个路由的最大连接
manager.setValidateAfterInactivity(5 * 1000);//在从连接池获取连接时，连接不活跃多长时间后需要进行一次验证，默认为2s
//配置默认的请求参数
RequestConfig defaultRequestConfig = RequestConfig.custom()
.setConnectTimeout(2 * 1000)//连接超时设置为2s
.setSocketTimeout(5 * 1000)//等待数据超时设置为5s
.setConnectionRequestTimeout(2 * 1000)//从连接池获取连接的等待超时时间设置为2s
// .setProxy(new Proxy(Proxy.Type.HTTP, new InetSocketAddress("192.168.0.2", 1234))) //设置代理
.build();
CloseableHttpClient closeableHttpClient = HttpClients.custom()
.setConnectionManager(manager)
.setConnectionManagerShared(false)//连接池不是共享模式，这个共享是指与其它httpClient是否共享
.evictIdleConnections(60, TimeUnit.SECONDS)//定期回收空闲连接
.evictExpiredConnections()//回收过期连接
.setConnectionTimeToLive(60, TimeUnit.SECONDS)//连接存活时间，如果不设置，则根据长连接信息决定
.setDefaultRequestConfig(defaultRequestConfig)//设置默认的请求参数
.setConnectionReuseStrategy(DefaultConnectionReuseStrategy.INSTANCE)//连接重用策略，即是否能keepAlive
.setKeepAliveStrategy(DefaultConnectionKeepAliveStrategy.INSTANCE)//长连接配置，即获取长连接生产多长时间
.setRetryHandler(new DefaultHttpRequestRetryHandler(0, false))//设置重试次数，默认为3次；当前是禁用掉
.build();
/**
*JVM停止或重启时，关闭连接池释放掉连接
*/
Runtime.getRuntime().addShutdownHook(new Thread() {
@Override
public void run() {
try {
closeableHttpClient.close();
log.info("http client closed");
} catch (IOException e) {
log.error(e.getMessage(), e);
}
}
});
return closeableHttpClient;
}
private CloseableHttpClient getHttpClient() {
//注册访问协议相关的Socket工厂
Registry<ConnectionSocketFactory> socketFactoryRegistry = RegistryBuilder.<ConnectionSocketFactory>create()
.register("http", PlainConnectionSocketFactory.INSTANCE)
.register("https", SSLConnectionSocketFactory.getSocketFactory())
.build();
//HttpConnectionFactory:配置写请求/解析响应处理器
HttpConnectionFactory<HttpRoute, ManagedHttpClientConnection> connectionFactory = new ManagedHttpClientConnectionFactory(
DefaultHttpRequestWriterFactory.INSTANCE,
DefaultHttpResponseParserFactory.INSTANCE
);
//DNS解析器
DnsResolver dnsResolver = SystemDefaultDnsResolver.INSTANCE;
//创建连接池管理器
PoolingHttpClientConnectionManager manager = new PoolingHttpClientConnectionManager(socketFactoryRegistry, connectionFactory, dnsResolver);
//设置默认的socket参数
manager.setDefaultSocketConfig(SocketConfig.custom().setTcpNoDelay(true).build());
manager.setMaxTotal(300);//设置最大连接数。高于这个值时，新连接请求，需要阻塞，排队等待
//路由是对MaxTotal的细分。
// 每个路由实际最大连接数默认值是由DefaultMaxPerRoute控制。
// MaxPerRoute设置的过小，无法支持大并发：ConnectionPoolTimeoutException:Timeout waiting for connection from pool
manager.setDefaultMaxPerRoute(200);//每个路由的最大连接
manager.setValidateAfterInactivity(5 * 1000);//在从连接池获取连接时，连接不活跃多长时间后需要进行一次验证，默认为2s
//配置默认的请求参数
RequestConfig defaultRequestConfig = RequestConfig.custom()
.setConnectTimeout(2 * 1000)//连接超时设置为2s
.setSocketTimeout(5 * 1000)//等待数据超时设置为5s
.setConnectionRequestTimeout(2 * 1000)//从连接池获取连接的等待超时时间设置为2s
// .setProxy(new Proxy(Proxy.Type.HTTP, new InetSocketAddress("192.168.0.2", 1234))) //设置代理
.build();
CloseableHttpClient closeableHttpClient = HttpClients.custom()
.setConnectionManager(manager)
.setConnectionManagerShared(false)//连接池不是共享模式，这个共享是指与其它httpClient是否共享
.evictIdleConnections(60, TimeUnit.SECONDS)//定期回收空闲连接
.evictExpiredConnections()//回收过期连接
.setConnectionTimeToLive(60, TimeUnit.SECONDS)//连接存活时间，如果不设置，则根据长连接信息决定
.setDefaultRequestConfig(defaultRequestConfig)//设置默认的请求参数
.setConnectionReuseStrategy(DefaultConnectionReuseStrategy.INSTANCE)//连接重用策略，即是否能keepAlive
.setKeepAliveStrategy(DefaultConnectionKeepAliveStrategy.INSTANCE)//长连接配置，即获取长连接生产多长时间
.setRetryHandler(new DefaultHttpRequestRetryHandler(0, false))//设置重试次数，默认为3次；当前是禁用掉
.build();
/**
*JVM停止或重启时，关闭连接池释放掉连接
*/
Runtime.getRuntime().addShutdownHook(new Thread() {
@Override
public void run() {
try {
LOGGER.info("closing http client");
closeableHttpClient.close();
LOGGER.info("http client closed");
} catch (IOException e) {
LOGGER.error(e.getMessage(), e);
}
}
});
return closeableHttpClient;
}