本文要介绍的这个工具类,是基于RestTemplate
做了一层代码封装!!非常好用哦!
- 第一步添加
httpclient
依赖包
<dependency>
<groupId>org.apache.httpcomponents</groupId>
<artifactId>httpclient</artifactId>
<version>4.5.6</version>
</dependency>
- 然后创建一个配置,初始化
RestTemplate
@Configuration
public class HttpConfiguration {
/**
* 初始化RestTemplate
* @return
*/
@ConditionalOnMissingBean(RestTemplate.class)
@Bean
public RestTemplate restTemplate(){
RestTemplate restTemplate = new RestTemplate(getClientHttpRequestFactory());
return restTemplate;
}
/**
* 使用HttpClient作为底层客户端
* @return
*/
private ClientHttpRequestFactory getClientHttpRequestFactory() {
int timeout = 5000;
RequestConfig config = RequestConfig.custom()
.setConnectTimeout(timeout)
.setConnectionRequestTimeout(timeout)
.setSocketTimeout(timeout)
.build();
CloseableHttpClient client = HttpClientBuilder
.create()
.setDefaultRequestConfig(config)
.build();
return new HttpComponentsClientHttpRequestFactory(client);
}
}
- 接着 创建一个
HttpTemplate
类,交给Spring
管理
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.core.ParameterizedTypeReference;
import org.springframework.http.*;
import org.springframework.stereotype.Component;
import org.springframework.util.LinkedMultiValueMap;
import org.springframework.util.MultiValueMap;
import org.springframework.web.client.RequestCallback;
import org.springframework.web.client.ResponseExtractor;
import org.springframework.web.client.RestTemplate;
import java.net.URI;
import java.util.Arrays;
import java.util.Map;
import java.util.Objects;
@Component
public class HttpTemplate {
private static final Logger log = LoggerFactory.getLogger(HttpTemplate.class);
@Autowired
private RestTemplate restTemplate;
/**
* get请求,返回响应实体(响应业务对象不支持范型)
* 支持restful风格
* @param url
* @param headers
* @param responseType
* @param uriVariables
* @param <T>
* @return
*/
public <T> T get(String url, Map<String, String> headers, Class<T> responseType, Object... uriVariables){
ResponseEntity<T> rsp = commonExchange(url, HttpMethod.GET, new HttpEntity<>(createHeaders(headers)), responseType, uriVariables);
return buildResponse(rsp);
}
/**
* get请求,返回响应实体(响应业务对象支持范型)
* 支持restful风格
* @param url
* @param headers
* @param responseType
* @param uriVariables
* @param <T>
* @return
*/
public <T> T get(String url, Map<String, String> headers, ParameterizedTypeReference<T> responseType, Object... uriVariables){
ResponseEntity<T> rsp = commonExchange(url, HttpMethod.GET, new HttpEntity<>(createHeaders(headers)), responseType, uriVariables);
return buildResponse(rsp);
}
/**
* post请求,form表单提交(响应业务对象不支持范型)
* 支持restful风格
* @param url
* @param headers
* @param paramMap
* @param responseType
* @param uriVariables
* @param <T>
* @return
*/
public <T> T postByFrom(String url, Map<String, String> headers, Map<String, Object> paramMap, Class<T> responseType, Object... uriVariables){
//指定请求头为表单类型
HttpHeaders httpHeaders = createHeaders(headers);
httpHeaders.setContentType(MediaType.APPLICATION_FORM_URLENCODED);
ResponseEntity<T> rsp = commonExchange(url, HttpMethod.POST, new HttpEntity<>(createBody(paramMap), httpHeaders), responseType, uriVariables);
return buildResponse(rsp);
}
/**
* post请求,form表单提交(响应业务对象支持范型)
* 支持restful风格
* @param url
* @param headers
* @param paramMap
* @param responseType
* @param uriVariables
* @param <T>
* @return
*/
public <T> T postByFrom(String url, Map<String, String> headers, Map<String, Object> paramMap, ParameterizedTypeReference<T> responseType, Object... uriVariables){
//指定请求头为表单类型
HttpHeaders httpHeaders = createHeaders(headers);
httpHeaders.setContentType(MediaType.APPLICATION_FORM_URLENCODED);
ResponseEntity<T> rsp = commonExchange(url, HttpMethod.POST, new HttpEntity<>(createBody(paramMap), httpHeaders), responseType, uriVariables);
return buildResponse(rsp);
}
/**
* post请求,json提交(响应业务对象不支持范型)
* 支持restful风格
* @param url
* @param headers
* @param request
* @param responseType
* @param uriVariables
* @param <T>
* @return
*/
public <T> T postByJson(String url, Map<String, String> headers, Object request, Class<T> responseType, Object... uriVariables){
//指定请求头为json类型
HttpHeaders httpHeaders = createHeaders(headers);
httpHeaders.setContentType(MediaType.APPLICATION_JSON_UTF8);
ResponseEntity<T> rsp = commonExchange(url, HttpMethod.POST, new HttpEntity<>(request, httpHeaders), responseType, uriVariables);
return buildResponse(rsp);
}
/**
* post请求,json提交(响应业务对象支持范型)
* 支持restful风格
* @param url
* @param headers
* @param request
* @param responseType
* @param uriVariables
* @param <T>
* @return
*/
public <T> T postByJson(String url, Map<String, String> headers, Object request, ParameterizedTypeReference<T> responseType, Object... uriVariables){
//指定请求头为json类型
HttpHeaders httpHeaders = createHeaders(headers);
httpHeaders.setContentType(MediaType.APPLICATION_JSON_UTF8);
ResponseEntity<T> rsp = commonExchange(url, HttpMethod.POST, new HttpEntity<>(request, httpHeaders), responseType, uriVariables);
return buildResponse(rsp);
}
/**
* post请求,json提交,重定项
* 支持restful风格
* @param url
* @param headers
* @param request
* @param uriVariables
* @return
*/
public String postForLocation(String url, Map<String, String> headers, Object request, Object... uriVariables){
//指定请求头为json类型
HttpHeaders httpHeaders = createHeaders(headers);
httpHeaders.setContentType(MediaType.APPLICATION_JSON_UTF8);
URI uri = restTemplate.postForLocation(url, new HttpEntity<>(request, httpHeaders), uriVariables);
if(Objects.nonNull(uri)){
return uri.toString();
}
return null;
}
/**
* put请求,json提交(响应业务对象不支持范型)
* @param url
* @param headers
* @param request
* @param uriVariables
*/
public <T> T put(String url, Map<String, String> headers, Object request, Class<T> responseType, Object... uriVariables){
//指定请求头为json类型
HttpHeaders httpHeaders = createHeaders(headers);
httpHeaders.setContentType(MediaType.APPLICATION_JSON_UTF8);
ResponseEntity<T> rsp = commonExchange(url, HttpMethod.PUT, new HttpEntity<>(request, httpHeaders), responseType, uriVariables);
return buildResponse(rsp);
}
/**
* put请求,json提交(响应业务对象支持范型)
* @param url
* @param headers
* @param request
* @param uriVariables
*/
public <T> T put(String url, Map<String, String> headers, Object request, ParameterizedTypeReference<T> responseType, Object... uriVariables){
//指定请求头为json类型
HttpHeaders httpHeaders = createHeaders(headers);
httpHeaders.setContentType(MediaType.APPLICATION_JSON_UTF8);
ResponseEntity<T> rsp = commonExchange(url, HttpMethod.PUT, new HttpEntity<>(request, httpHeaders), responseType, uriVariables);
return buildResponse(rsp);
}
/**
* delete请求(响应业务对象不支持范型)
* @param url
* @param headers
* @param uriVariables
* @return
*/
public <T> T delete(String url, Map<String, String> headers, Class<T> responseType, Object... uriVariables){
ResponseEntity<T> rsp = commonExchange(url, HttpMethod.DELETE, new HttpEntity<>(createHeaders(headers)), responseType, uriVariables);
return buildResponse(rsp);
}
/**
* delete请求(响应业务对象支持范型)
* @param url
* @param headers
* @param uriVariables
* @return
*/
public <T> T delete(String url, Map<String, String> headers, ParameterizedTypeReference<T> responseType, Object... uriVariables){
ResponseEntity<T> rsp = commonExchange(url, HttpMethod.DELETE, new HttpEntity<>(createHeaders(headers)), responseType, uriVariables);
return buildResponse(rsp);
}
/**
* post请求,文件表单上传提交(响应业务对象不支持范型)
* 支持restful风格
* @param url
* @param headers
* @param paramMap
* @param responseType
* @param uriVariables
* @param <T>
* @return
*/
public <T> T uploadFile(String url, Map<String, String> headers, MultiValueMap<String, Object> paramMap, Class<T> responseType, Object... uriVariables){
//指定请求头为文件&表单类型
HttpHeaders httpHeaders = createHeaders(headers);
httpHeaders.setContentType(MediaType.MULTIPART_FORM_DATA);
ResponseEntity<T> rsp = commonExchange(url, HttpMethod.POST, new HttpEntity<>(paramMap, httpHeaders), responseType, uriVariables);
return buildResponse(rsp);
}
/**
* post请求,文件表单上传提交(响应业务对象支持范型)
* 支持restful风格
* @param url
* @param headers
* @param paramMap
* @param responseType
* @param uriVariables
* @param <T>
* @return
*/
public <T> T uploadFile(String url, Map<String, String> headers, MultiValueMap<String, Object> paramMap, ParameterizedTypeReference<T> responseType, Object... uriVariables){
//指定请求头为文件&表单类型
HttpHeaders httpHeaders = createHeaders(headers);
httpHeaders.setContentType(MediaType.MULTIPART_FORM_DATA);
ResponseEntity<T> rsp = commonExchange(url, HttpMethod.POST, new HttpEntity<>(paramMap, httpHeaders), responseType, uriVariables);
return buildResponse(rsp);
}
/**
* 下载文件
* @param url
* @param headers
* @param uriVariables
* @return
*/
public byte[] downloadFile(String url, Map<String, String> headers, Object... uriVariables){
ResponseEntity<byte[]> rsp = commonExchange(url, HttpMethod.GET, new HttpEntity<>(createHeaders(headers)), byte[].class, uriVariables);
return buildResponse(rsp);
}
/**
* 下载大文件
* @param url
* @param headers
* @param responseExtractor
* @param uriVariables
*/
public void downloadBigFile(String url, Map<String, String> headers, ResponseExtractor responseExtractor, Object... uriVariables){
RequestCallback requestCallback = request -> {
//指定请求头信息
request.getHeaders().addAll(createHeaders(headers));
//定义请求头的接收类型
request.getHeaders().setAccept(Arrays.asList(MediaType.APPLICATION_OCTET_STREAM, MediaType.ALL));
};
restTemplate.execute(url, HttpMethod.GET, requestCallback,responseExtractor, uriVariables);
}
/**
* 公共http请求方法(响应业务对象不支持范型)
* @param url
* @param method
* @param requestEntity
* @param responseType
* @param uriVariables
* @param <T>
* @return
*/
public <T> ResponseEntity<T> commonExchange(String url, HttpMethod method, HttpEntity<?> requestEntity, Class<T> responseType, Object... uriVariables){
return restTemplate.exchange(url, method, requestEntity, responseType, uriVariables);
}
/**
* 公共http请求方法(响应业务对象支持范型)
* @param url
* @param method
* @param requestEntity
* @param responseType
* @param uriVariables
* @param <T>
* @return
*/
public <T> ResponseEntity<T> commonExchange(String url, HttpMethod method, HttpEntity<?> requestEntity, ParameterizedTypeReference<T> responseType, Object... uriVariables){
return restTemplate.exchange(url, method, requestEntity, responseType, uriVariables);
}
/**
* 封装头部参数
* @param headers
* @return
*/
private HttpHeaders createHeaders(Map<String, String> headers){
return new HttpHeaders(){{
if(headers != null && !headers.isEmpty()){
headers.entrySet().forEach(item -> {
set(item.getKey(), item.getValue());
});
}
}};
}
/**
* 封装请求体
* @param paramMap
* @return
*/
private MultiValueMap<String, Object> createBody(Map<String, Object> paramMap){
MultiValueMap<String, Object> valueMap = new LinkedMultiValueMap<>();
if(paramMap != null && !paramMap.isEmpty()){
paramMap.entrySet().forEach(item -> {
valueMap.add(item.getKey(), item.getValue());
});
}
return valueMap;
}
/**
* 返回响应对象
* @param rsp
* @param <T>
* @return
*/
private <T> T buildResponse(ResponseEntity<T> rsp){
if(!rsp.getStatusCode().is2xxSuccessful()){
throw new RuntimeException(rsp.getStatusCode().getReasonPhrase());
}
return rsp.getBody();
}
}
当遇到返回的对象是范型类型的时候,我们可以这样操作!
以下面这个/testPostByJsonObj
接口为例!
/**
* 模拟JSON请求,post方法测试
* @param request
* @return
*/
@RequestMapping(value = "testPostByJsonObj", method = RequestMethod.POST)
public ResponseBeanObj<ResponseBean> testPostByJsonObj(@RequestBody RequestBean requestBean,
HttpServletRequest request){
HttpServletRequestLog.systemLog(request);
//范型测试
ResponseBean responseBean = new ResponseBean();
responseBean.setCode("200000");
responseBean.setMsg("responseBean");
//范型测试
ResponseBeanObj<ResponseBean> result = new ResponseBeanObj<>();
result.setCode("200");
result.setMsg("请求成功,方法:testPostByJsonObj,请求参数:" + JSON.toJSONString(requestBean));
result.setObj(responseBean);
System.out.println(JSON.toJSONString(result));
return result;
}
使用RestTemplate
工具发起网络请求,代码如下!
//将返回的范型对象包装到ParameterizedTypeReference对象里面
ParameterizedTypeReference<ResponseBeanObj<ResponseBean>> typeRef = new ParameterizedTypeReference<ResponseBeanObj<ResponseBean>>() {};
//使用restTemplate发起网络请求
ResponseBeanObj<ResponseBean> responseBean = restTemplate.exchange(url, HttpMethod.POST, request, typeRef);
采用restTemplate.exchange()
方法,即可实现返回对象范型类型的反序列化!
如果使用上面封装的HttpTemplate
工具进行操作,也更简单,代码如下:
/**
* 模拟JSON提交,post请求,范型返回对象测试
*/
@Test
public void testPostByJsonObj(){
//请求地址
String url = "http://localhost:8080/testPostByJsonObj";
//入参
RequestBean request = new RequestBean();
request.setUserName("唐三藏");
request.setUserPwd("123456789");
//发送post请求
ParameterizedTypeReference<ResponseBeanObj<ResponseBean>> typeRef = new ParameterizedTypeReference<ResponseBeanObj<ResponseBean>>() {};
//范型测试
ResponseBeanObj<ResponseBean> responseBean = httpTemplate.postByJson(url, createHeader("testPostByJsonObj"), request, typeRef);
System.out.println(JSON.toJSONString(responseBean));
}
在某些场景下,当你使用restTemplate
发起网络请求时,所有的请求头部需要带上统一的参数,例如Authorization
鉴权码,what can I do?
那我们可以在RestTemplate
初始化之后,添加一个拦截器,然后在拦截器的请求头部统一注入鉴权码,就可以轻松实现全局加入某个参数,方式如下!
/**
* 初始化RestTemplate
* @return
*/
@Bean
public RestTemplate restTemplate(){
RestTemplate restTemplate = new RestTemplate(getClientHttpRequestFactory());
// 添加一个拦截器,在请求头部添加 Authorization 鉴权码
restTemplate.getInterceptors().add((request, body, execution) -> {
request.getHeaders().add("Authorization", "xxxxxXXXXX");
return execution.execute(request, body);
});
return restTemplate;
}
最后说一句(求关注!别白嫖!)
如果这篇文章对您有所帮助,或者有所启发的话,求一键三连:点赞、转发、在看。
关注公众号:woniuxgg,在公众号中回复:笔记 就可以获得蜗牛为你精心准备的java实战语雀笔记,回复面试、开发手册、有超赞的粉丝福利!