是由 Spring 软件系统开发定制提供的一个 HTTP 请求工具,软件系统开发定制它提供了常见的REST请求方案的模版,例如 GET 请求、POST 请求、PUT 请求、DELETE 请求以及一些通用的请求执行方法 exchange 以及 execute。RestTemplate 继承自 InterceptingHttpAccessor 并且实现了 RestOperations 接口,其中 RestOperations 接口定义了基本的 RESTful 操作,这些操作在 RestTemplate 中都得到了实现。
POST请求
postForObject
1、使用LinkedMultiValueMap作为参数(Form表单提交)
- RestTemplate template = new RestTemplate();
- String url = "http://127.0.0.1:8800/product/update";
-
- MultiValueMap<String, Object> paramMap = new LinkedMultiValueMap<String, Object>();
- paramMap.add("id", "123");
- paramMap.add("name", "张三");
- String result = template.postForObject(url, paramMap, String.class);
- System.out.println("result:" + result);
2、使用Object作为参数(JSON提交)
- RestTemplate template = new RestTemplate();
- String url = "http://127.0.0.1:8800/product/update";
-
- User user = new User(123, "张三");
- String result = template.postForObject(url, user, String.class);
- System.out.println("result:" + result);
3、使用JSONObject作为参数(JSON提交)
- RestTemplate template = new RestTemplate();
- String url = "http://127.0.0.1:8800/product/update";
-
- JSONObject obj = new JSONObject();
- obj.put("id", "123");
- obj.put("name", "张三");
- String result = template.postForObject(url, obj, String.class);
- System.out.println("result:" + result);
postForEntity
1、使用LinkedMultiValueMap作为参数(Form表单提交)
- RestTemplate template = new RestTemplate();
- String url = "http://127.0.0.1:8800/product/update";
-
- HttpHeaders headers = new HttpHeaders();
- headers.set("token", "asdf");
-
- MultiValueMap<String, Object> paramMap = new LinkedMultiValueMap<String, Object>();
- paramMap.add("id", "123");
- paramMap.add("name", "张三");
-
- HttpEntity<MultiValueMap<String, Object>> httpEntity = new HttpEntity<MultiValueMap<String, Object>>(paramMap, headers);
- ResponseEntity<String> response = template.postForEntity(url, httpEntity, String.class);
- System.out.println("result:" + response.getBody());
2、使用Object作为参数(JSON提交)
- RestTemplate template = new RestTemplate();
- String url = "http://127.0.0.1:8800/product/update";
-
- HttpHeaders headers = new HttpHeaders();
-
- User user = new User(123, "张三");
- HttpEntity<User> httpEntity = new HttpEntity<User>(user, headers);
- ResponseEntity<String> response = template.postForEntity(url, httpEntity, String.class);
- System.out.println("result:" + response.getBody());
3、使用JSONObject为参数(JSON提交)
- RestTemplate template = new RestTemplate();
- String url = "http://127.0.0.1:8800/product/update";
-
- HttpHeaders headers = new HttpHeaders();
-
- JSONObject obj = new JSONObject();
- obj.put("id", "123");
- obj.put("name", "张三");
- HttpEntity<JSONObject> httpEntity = new HttpEntity<JSONObject>(obj, headers);
- ResponseEntity<String> response = template.postForEntity(url, httpEntity, String.class);
- System.out.println("result:" + response.getBody());
exchange
- RestTemplate template = new RestTemplate();
- String url = "http://127.0.0.1:8800/product/productDetail";
-
- HttpHeaders headers = new HttpHeaders();
- MultiValueMap<String, Object> paramMap = new LinkedMultiValueMap<String, Object>();
- paramMap.add("id", "123");
-
- HttpEntity<MultiValueMap<String, Object>> httpEntity = new HttpEntity<MultiValueMap<String, Object>>(paramMap, headers);
- ResponseEntity<String> response = template.exchange(url, HttpMethod.POST, httpEntity, String.class);
- System.out.println("result:" + response.getBody());
postForObject和postForEntity方法的区别主要在于可以在postForEntity方法中设置header的属性,当需要指定header的属性值的时候,使用postForEntity方法。
exchange方法和postForEntity类似,但是更灵活,exchange还可以调用get、put、delete请求。
GET请求
getForObject
- RestTemplate template = new RestTemplate();
- String url = "http://127.0.0.1:8800/product/detail?id={id}";
-
- Map<String, Object> paramMap = new HashMap<String, Object>();
- paramMap.put("id", "123");
-
- String result = template.getForObject(url, String.class, paramMap);
- System.out.println("result:" + result);
getForEntity
- RestTemplate template = new RestTemplate();
- String url = "http://127.0.0.1:8800/product/detail?id={id}";
-
- Map<String, Object> paramMap = new HashMap<String, Object>();
- paramMap.put("id", "123");
-
- ResponseEntity<String> response1 = template.getForEntity(url, String.class, paramMap);
- System.out.println("result:" + response1.getBody());
exchange
- RestTemplate template = new RestTemplate();
- String url = "http://127.0.0.1:8800/product/productDetail";
-
- HttpHeaders headers = new HttpHeaders();
- headers.set("token", "asdf");
-
- HttpEntity<MultiValueMap<String, Object>> httpEntity = new HttpEntity<MultiValueMap<String, Object>>(null, headers);
- ResponseEntity<String> response = template.exchange(url, HttpMethod.GET, httpEntity, String.class,paramMap);
- System.out.println("result:" + response.getBody());