HttpClient设置超时时间和连接次数

通过HttpClient发送请求时，需要设置请求超时时间、连接超时时间、读取数据超时时间等参数。用来避免因请求过程中等待时间太长，影响上下游交易的超时和服务器性能。

1.1设置http请求的连接超时时间-setConnectTimeout方法参数，单位毫秒（是建立连接的超时时间）

CloseableHttpClient  httpClient = HttpClientBuilder.create().build();

//设置http请求的连接超时时间

RequestConfig requestConfig =  RequestConfig.custom().setConnectTimeout(5000).build();

//创建post请求

HttpPost  httpPost = new HttpPost("http://192.168.1.123:8080/fqz");

String send = "{"a":"A","b":"BB"}";//请求的主体信息

StringEntity  entity = new StringEntity(send,"utf-8");//设置post请求的拜纳姆格式

httpPost.setEntity(entity);

httpPost.setHeader("Content-Type","application/json;charset=utf-8");//设置请求头

httpPost.setConfig(requestConfig);//设置请求参数【超时时间】

CloseableHttpResponse  response =  httpClient.execute(httpPost);

1.2设置http请求的读取数据超时时间-setSocketTimeout方法参数，单位毫秒（如果访问一个接口，多少时间内无法返回数据，就直接放弃此次调用）

CloseableHttpClient  httpClient = HttpClientBuilder.create().build();

//设置http请求的读取数据超时时间

RequestConfig requestConfig =  RequestConfig.custom().setSocketTimeout(5000).build();

//创建post请求

HttpPost  httpPost = new HttpPost("http://192.168.1.123:8080/fqz");

String send = "{"a":"A","b":"BB"}";//请求的主体信息

StringEntity  entity = new StringEntity(send,"utf-8");//设置post请求的拜纳姆格式

httpPost.setEntity(entity);

httpPost.setHeader("Content-Type","application/json;charset=utf-8");//设置请求头

httpPost.setConfig(requestConfig);//设置请求参数【超时时间】

CloseableHttpResponse  response =  httpClient.execute(httpPost);

1.3设置http请求的超时时间- setConnectionRequestTimeout方法参数，单位毫秒（一般没有通过连接池获取连接不需要设置）

CloseableHttpClient  httpClient = HttpClientBuilder.create().build();

//设置http请求的超时时间，指等待连接池中可用连接的时间，超过这个时间会抛出ConnectionPoolTimeoutException异常

RequestConfig requestConfig = RequestConfig.custom().setConnectionRequestTimeout (5000).build();

//创建post请求

HttpPost  httpPost = new HttpPost("http://192.168.1.123:8080/fqz");

String send = "{"a":"A","b":"BB"}";//请求的主体信息

StringEntity  entity = new StringEntity(send,"utf-8");//设置post请求的拜纳姆格式

httpPost.setEntity(entity);

httpPost.setHeader("Content-Type","application/json;charset=utf-8");//设置请求头

httpPost.setConfig(requestConfig);//设置请求参数【超时时间】

CloseableHttpResponse  response =  httpClient.execute(httpPost);

1.4  设置Http请求的重试次数,参数设置setMaxRedirects方法，超过这个次数会抛出TooManyRedirectsException异常

CloseableHttpClient  httpClient = HttpClientBuilder.create().build();

//设置http请求的重试次数

RequestConfig requestConfig = RequestConfig.custom().setMaxRedirect s(3).build();

//创建post请求

HttpPost  httpPost = new HttpPost("http://192.168.1.123:8080/fqz");

String send = "{"a":"A","b":"BB"}";//请求的主体信息

StringEntity  entity = new StringEntity(send,"utf-8");//设置post请求的拜纳姆格式

httpPost.setEntity(entity);

httpPost.setHeader("Content-Type","application/json;charset=utf-8");//设置请求头

httpPost.setConfig(requestConfig);//设置请求参数【请求重试次数】

CloseableHttpResponse  response =  httpClient.execute(httpPost);