****spring boot-----restTemplate
封装了HttpURLConnection,HttpClient,Netty等接口访问实现库
restTemplet包含以下部分
HttpMessageConverter ClientHttpRequestFactory -->HttpURLConnection ResponseErrorHandler ClientHttpRequestInterceptor
部分实例代码
（1）发送GET请求（getForObject()、getForEntity()、exchange()）
// 1-getForObject()
User user1 = this.restTemplate.getForObject(uri, User.class);
// 2-getForEntity()
ResponseEntity responseEntity1 = this.restTemplate.getForEntity(uri, User.class);
HttpStatus statusCode = responseEntity1.getStatusCode();
HttpHeaders header = responseEntity1.getHeaders();
User user2 = responseEntity1.getBody();
// 3-exchange()
RequestEntity requestEntity = RequestEntity.get(new URI(uri)).build();
ResponseEntity responseEntity2 = this.restTemplate.exchange(requestEntity, User.class);
User user3 = responseEntity2.getBody();
（2）发送POST请求（postForObject()、postForEntity()、exchange()）
// 1-postForObject()
User user1 = this.restTemplate.postForObject(uri, user, User.class);
// 2-postForEntity()
ResponseEntity responseEntity1 = this.restTemplate.postForEntity(uri, user, User.class);
// 3-exchange()
RequestEntity requestEntity = RequestEntity.post(new URI(uri)).body(user);
ResponseEntity responseEntity2 = this.restTemplate.exchange(requestEntity, User.class);
（3）设置HTTP Header信息
//1-postForObject()
User user1 = this.restTemplate.postForObject(uri, user, User.class);
// 2-postForEntity()
ResponseEntity responseEntity1 = this.restTemplate.postForEntity(uri, user, User.class);
// 3-exchange()
RequestEntity requestEntity = RequestEntity.post(new URI(uri)).body(user);
ResponseEntity responseEntity2 = this.restTemplate.exchange(requestEntity, User.class);
（4）设置HTTP Header信息 ##
@Configuration
public class RestClientConfig {
@Bean
public ClientHttpRequestFactory httpRequestFactory() {
return new HttpComponentsClientHttpRequestFactory(httpClient());
}
@Bean
public RestTemplate restTemplate() {
return new RestTemplate(httpRequestFactory());
}
@Bean
public HttpClient httpClient() {
Registry registry = RegistryBuilder. create()
.register("http", PlainConnectionSocketFactory.getSocketFactory())
.register("https", SSLConnectionSocketFactory.getSocketFactory())
.build();
PoolingHttpClientConnectionManager connectionManager = new PoolingHttpClientConnectionManager(registry);
connectionManager.setMaxTotal(5);
connectionManager.setDefaultMaxPerRoute(5);
RequestConfig requestConfig = RequestConfig.custom()
.setSocketTimeout(8000)
.setConnectTimeout(8000)
.setConnectionRequestTimeout(8000)
.build();
return HttpClientBuilder.create()
.setDefaultRequestConfig(requestConfig)
.setConnectionManager(connectionManager)
.build();
}
}