RestTemplate使用 RestTemplate使用一、依赖注入 @Bean // 开启负载均衡 @LoadBalanced RestTemplate restTemplate() { return new RestTemplate(); }二、调用服务String url ="http://provider/getHi"; String respStr = restTemplate.getForObject(url, String.class);三、get 请求1、getForEntitygetForEntity方法的返回值是一个ResponseEntity，ResponseEntity是Spring对HTTP请求响应的封装，包括了几个重要的元素，如响应码、contentType、contentLength、响应消息体等。<200,Hi,[Content-Type:"text/plain;charset=UTF-8", Content-Length:"8", Date:"Fri, 10 Apr 2020 09:58:44 GMT", Keep-Alive:"timeout=60", Connection:"keep-alive"]>2、返回Map调用方 String url ="http://provider/getMap"; ResponseEntity<Map> entity = restTemplate.getForEntity(url, Map.class); System.out.println("respStr: " + entity.getBody() );生产方 @GetMapping("/getMap") public Map<String, String> getMap() { HashMap<String, String> map = new HashMap<>(); map.put("name", "500"); return map; }3、返回对象(getForEntity)调用方 ResponseEntity<Person> entity = restTemplate.getForEntity(url, Person.class); System.out.println("respStr: " + ToStringBuilder.reflectionToString(entity.getBody() ));生产方 @GetMapping("/getObj") public Person getObj() { Person person = new Person(); person.setId(100); person.setName("xiaoming"); return person; }Person类 private int id; private String name;4、传参调用4.1、使用占位符 String url ="http://provider/getObjParam?name={1}"; ResponseEntity<Person> entity = restTemplate.getForEntity(url, Person.class,"hehehe...");4.2、使用map String url ="http://provider/getObjParam?name={name}"; Map<String, String> map = Collections.singletonMap("name", " memeda"); ResponseEntity<Person> entity = restTemplate.getForEntity(url, Person.class,map);5、返回对象（getForObject）Person person = restTemplate.getForObject(url, Person.class,map);四、post 请求1、postForEntity调用方 String url ="http://provider/postParam"; Map<String, String> map = Collections.singletonMap("name", " memeda"); ResponseEntity<Person> entity = restTemplate.postForEntity(url, map, Person.class);生产方 @PostMapping("/postParam") public Person postParam(@RequestBody String name) { System.out.println("name:" + name); Person person = new Person(); person.setId(100); person.setName("xiaoming" + name); return person; }2、postForLocation调用方 String url ="http://provider/postParam"; Map<String, String> map = Collections.singletonMap("name", " memeda"); URI location = restTemplate.postForLocation(url, map, Person.class); System.out.println(location);生产方需要设置头信息，不然返回的是null public URI postParam(@RequestBody Person person,HttpServletResponse response) throws Exception { URI uri = new URI("https://www.baidu.com/s?wd="+person.getName()); response.addHeader("Location", uri.toString());五、exchange可以自定义http请求的头信息，同时保护get和post方法第一步：自定义拦截器需要实现ClientHttpRequestInterceptor接口public class LoggingClientHttpRequestInterceptor implements ClientHttpRequestInterceptor { @Override public ClientHttpResponse intercept(HttpRequest request, byte[] body, ClientHttpRequestExecution execution) throws IOException { System.out.println("拦截啦！！！"); System.out.println(request.getURI()); ClientHttpResponse response = execution.execute(request, body); System.out.println(response.getHeaders()); return response; }第二步：添加到RestTemplate中 @Bean @LoadBalanced RestTemplate restTemplate() { RestTemplate restTemplate = new RestTemplate(); restTemplate.getInterceptors().add(new LoggingClientHttpRequestInterceptor()); return restTemplate; }