一、RestTemplate
RestTemplate 是简化了组装请求对象 该类存在于 依赖 spring-boot-starter-web中，RestTemplate 支持get,post 现 1、RestTemplate 不是可直接注入Bean， 需要实例化生成Bean Spring Boot 的自动配置机制非常强大，但并不是所有的类都被默认自动配置为 bean。对于 RestTemplate 来说，Spring Boot 并没有默认自动配置一个 RestTemplate bean，主要原因有以下几点： 1）、多样化的配置需求 2）、鼓励显式配置 3）、灵活性和扩展性：显式配置使得应用更加灵活，可以根据需要创建和配置多个不同的1、简单方式生成Bean
@Configuration
public class AppConfig {
@Bean
public RestTemplate restTemplate() {
return new RestTemplate();
}
}
2、自定义参数 生成Bean
@Configuration
public class RestTemplateAutoConfiguration {
private final RestTemplateBuilder builder;
public RestTemplateAutoConfiguration(RestTemplateBuilder builder) {
this.builder = builder;
}
@Bean
public RestTemplate restTemplate() {
return builder
.setConnectTimeout(Duration.ofSeconds(3))
.setReadTimeout(Duration.ofMillis(PushTaskConstant.DEFAULT_REQUEST_TIME))
.requestFactory(() -> new HttpComponentsClientHttpRequestFactory(
HttpClientBuilder.create()
.setMaxConnTotal(200)
.setMaxConnPerRoute(40)
.disableAutomaticRetries()
.useSystemProperties().build())
).build();
}
}
2、在重点介绍post请求试
1）请求 当请求类型contentType是MediaType.APPLICATION_FORM_URLENCODED
1、请求方法
@Resource
RestTemplate restTemplate;
@Test
public void testRequest(){
headers.setContentType(MediaType.APPLICATION_FORM_URLENCODED);
// 当请求类型contentType是MediaType.APPLICATION_FORM_URLENCODED，请求参数实体必须是MultiValueMap
MultiValueMap<String,String> requestBody=new LinkedMultiValueMap<>();
requestBody.add("userName","testregisterName");
requestBody.add("loginNo","testReg");
requestBody.add("contactPhone","15210212542");
requestBody.add("smsCode","3820");
// 请求和header组合用entity
HttpEntity<MultiValueMap<String, String>> entity = new HttpEntity<>(requestBody, headers);
ResponseEntity response= restTemplate.postForEntity("http://testapi-xxxx.com/openApp/user/registerUser", entity, String.class);
System.out.println("response.getStatusCode() = " + response.getStatusCode());
System.out.println("response.getBody() = " + response.getBody());
}
2、接收方法
public ResultEntity<String> registerUser(RegisterUserRequest userRequest) {
}
2)当请求类型contentType是MediaType.APPLICATION_JSON
@Resource
RestTemplate restTemplate;
@Test
public void testRequest2(){
RestTemplate restTemplate = new RestTemplate();
headers.setContentType(MediaType.APPLICATION_JSON);
// 当contentType 是APPLICATION_JSON 请求参数对象用map
Map<String,String> requestEntity=new HashMap<>();
requestEntity.put("userName","testregisterName");
requestEntity.put("loginNo","testReg");
requestEntity.put("contactPhone","15210212542");
requestEntity.put("smsCode","3820");
// 请求和header组合用entity
HttpEntity<Map<String, String>> entity = new HttpEntity<>(requestEntity, headers);
ResponseEntity response= restTemplate.postForEntity("http://testapi-console.dmall.com/openApp/user/registerUser", entity, String.class);
System.out.println("response.getStatusCode() = " + response.getStatusCode());
System.out.println("response.getBody() = " + response.getBody());
}
ps：已有Bean的注入
1、第一种在配置类中 可以以参数注入
@Configuration
public class AppConfig {
@Bean
public RestTemplate restTemplate(RestTemplateBuilder builder) {
return builder
.setConnectTimeout(Duration.ofMillis(5000))
.setReadTimeout(Duration.ofMillis(5000))
.build();
}
-___________________________-
2、也可以正常以属性注入
@Configuration
public class AppConfig {
@Resource
private RestTemplateBuilder builder;
@Bean
public RestTemplate restTemplate() {
return builder
.setConnectTimeout(Duration.ofMillis(5000))
.setReadTimeout(Duration.ofMillis(5000))
.build();
}
}
二、 java 8 HttpClient
Apache HttpClient 适合需要更多配置和功能的场景
// 需要引入依赖
<dependency>
<groupId>org.apache.httpcomponents</groupId>
<artifactId>httpclient</artifactId>
<version>4.5.13</version>
</dependency>
实例调用 ps: 使用 httpClient 需要显示关闭或 try(){} ,try-with-resources 释放
@Test
public void testHttp() throws Exception{
try(CloseableHttpClient httpClient= HttpClients.createDefault()){
HttpPost httpPost=new HttpPost("http://testapi-console.dmall.com/openApp/user/registerUser");
// 可以自定义进行设置
// HttpClients.custom().build()
// HttpRequestRetryHandler retryHandler = new HttpRequestRetryHandler() {
// @Override
// public boolean retryRequest(IOException exception, int executionCount, HttpContext context) {
// if (executionCount >= 3) {
// return false; // 超过最大重试次数
// }
// if (exception instanceof org.apache.http.NoHttpResponseException) {
// return true; // 服务器无响应
// }
// if (exception instanceof java.net.SocketTimeoutException) {
// return true; // 超时
// }
// return false; // 不重试其他类型的异常
// }
// };
// 可以自定义进行配置信息
RequestConfig requestConfig=RequestConfig.custom()
.setConnectTimeout(5000)
.setSocketTimeout(5000)
.build();
httpPost.setConfig(requestConfig);
Map<String,String> parameters=new HashMap<>();
parameters.put("userName","testregisterName");
parameters.put("loginNo","testReg");
parameters.put("contactPhone","15210212542");
parameters.put("smsCode","3820");
StringJoiner stringJoiner=new StringJoiner("&");
for(Map.Entry entry:parameters.entrySet()){
stringJoiner.add(URLEncoder.encode(entry.getKey().toString(),"UTF-8")+"="+URLEncoder.encode(entry.getValue().toString(),"UTF-8"));
}
// httpPost.setHeader("Content-Type","application/x-www-form-urlencoded");
// httpPost.setEntity(new StringEntity(stringJoiner.toString()));
httpPost.setHeader("Content-Type",MediaType.APPLICATION_JSON_VALUE);
httpPost.setEntity(new StringEntity(JSON.toJSONString(parameters)));
HttpResponse response=httpClient.execute(httpPost);
System.out.println("response.getEntity().getContent().toString() = " + response.getEntity().getContent().toString());
String readStr="";
StringBuilder sb=new StringBuilder();
try(BufferedReader bufferedReader=new BufferedReader(new InputStreamReader(response.getEntity().getContent()))){
while ((readStr=bufferedReader.readLine())!=null){
sb.append(readStr);
}
}
System.out.println("stringJoiner = " + sb.toString());
}catch (Exception e){
e.printStackTrace();
throw e;
}
}
标签：restTemplate,RestTemplate,public,Bean,apache,new,response,HttpClient From： https://www.cnblogs.com/liyanbofly/p/18327957