Spring RestTemplate使用方法示例总结
作者：申城异乡人
这篇文章主要介绍了Spring RestTemplate使用方法示例总结,本文通过实例代码给大家介绍的非常详细,感兴趣的朋友一起看看吧
1. 引入依赖
首先，需要确认项目中是否直接或者间接引入过spring-web依赖，如果没有引入过，需要在pom.xml中添加以下代码引入依赖：
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-web</artifactId>
<version>4.3.24.RELEASE</version>
</dependency>2. 发送GET请求
使用RestTemplate发送GET请求主要有getForObject()和getForEntity()2个方法，每个方法分别提供了3种不同的重载。
2.1 使用getForObject发送GET请求(无参数)
使用getForObject()实现：
RestTemplate restTemplate = new RestTemplate(); String url = "https://www.example.com/getCurrentEnv"; String response = restTemplate.getForObject(url, String.class); System.out.println(response);
假设以上接口返回的报文为：
{
"serverAddress": "www.example.dev.com",
"env": "dev"
}也可以直接解析为自定义的类型：
import lombok.Getter;
import lombok.Setter;
@Getter
@Setter
public class EnvInfo {
private String serverAddress;
private String env;
}RestTemplate restTemplate = new RestTemplate(); String url = "https://www.example.com/getCurrentEnv"; EnvInfo response = restTemplate.getForObject(url, EnvInfo.class); System.out.println(JSON.toJSONString(response));
2.2 使用getForEntity发送GET请求(无参数)
也可以使用getForEntity()实现和2.1同样的功能，代码如下所示：
RestTemplate restTemplate = new RestTemplate();
String url = "https://www.example.com/getCurrentEnv";
ResponseEntity<EnvInfo> responseEntity = restTemplate.getForEntity(url, EnvInfo.class);
if (responseEntity.getStatusCode() == HttpStatus.OK) {
EnvInfo response = responseEntity.getBody();
System.out.println(JSON.toJSONString(response));
}2.3 使用getForObject发送GET请求(带参数)
第一种方法是直接在url上拼接上参数，如下所示：
RestTemplate restTemplate = new RestTemplate(); String url = "https://www.example.com/getDataList?pageIndex=1&pageSize=20"; EnvInfo response = restTemplate.getForObject(url, EnvInfo.class); System.out.println(JSON.toJSONString(response));
第二种方法是使用占位符添加参数，如下所示：
RestTemplate restTemplate = new RestTemplate();
String url = "https://www.example.com/getDataList?pageIndex={1}&pageSize={2}";
EnvInfo response = restTemplate.getForObject(url, EnvInfo.class, 1, 20);
System.out.println(JSON.toJSONString(response));以上代码也可以替换为：
RestTemplate restTemplate = new RestTemplate();
String url = "https://www.example.com/getDataList?pageIndex={pageIndex}&pageSize={pageSize}";
Map<String, String> uriVariables = new HashMap<>();
uriVariables.put("pageIndex", "1");
uriVariables.put("pageSize", "20");
EnvInfo response = restTemplate.getForObject(url, EnvInfo.class, uriVariables);
System.out.println(JSON.toJSONString(response));注意事项：
uriVariables中的key必须和url中的占位符名称一致，否则会抛出异常：
java.lang.IllegalArgumentException: Map has no value for 'pageIndex'
第三种方法是使用UriComponentsBuilder添加参数，该种方法相比于前两种方法更加灵活，可以实现动态添加参数，代码如下所示：
RestTemplate restTemplate = new RestTemplate();
String httpUrl = "https://www.example.com/getDataList";
UriComponentsBuilder uriComponentsBuilder = UriComponentsBuilder.fromHttpUrl(httpUrl);
uriComponentsBuilder.queryParam("pageIndex", 1);
uriComponentsBuilder.queryParam("pageSize", 20);
String url = uriComponentsBuilder.toUriString();
EnvInfo response = restTemplate.getForObject(url, EnvInfo.class);
System.out.println(JSON.toJSONString(response));2.4 使用getForEntity发送GET请求(带参数)
也可以使用getForEntity()实现和2.3同样的功能，代码如下所示：
RestTemplate restTemplate = new RestTemplate();
String httpUrl = "https://www.example.com/getDataList";
UriComponentsBuilder uriComponentsBuilder = UriComponentsBuilder.fromHttpUrl(httpUrl);
uriComponentsBuilder.queryParam("pageIndex", 1);
uriComponentsBuilder.queryParam("pageSize", 20);
String url = uriComponentsBuilder.toUriString();
ResponseEntity<EnvInfo> responseEntity = restTemplate.getForEntity(url, EnvInfo.class);
if (responseEntity.getStatusCode() == HttpStatus.OK) {
EnvInfo response = responseEntity.getBody();
System.out.println(JSON.toJSONString(response));
}
2.5 getForObject与getForEntity的区别
getForEntity()与getForObject()相比，返回值用了ResponseEntity进行封装，可以多获取到以下2种信息：
- HTTP状态码
- Response Headers
代码示例：
RestTemplate restTemplate = new RestTemplate();
String httpUrl = "https://www.example.com/getDataList";
UriComponentsBuilder uriComponentsBuilder = UriComponentsBuilder.fromHttpUrl(httpUrl);
uriComponentsBuilder.queryParam("pageIndex", 1);
uriComponentsBuilder.queryParam("pageSize", 20);
String url = uriComponentsBuilder.toUriString();
ResponseEntity<EnvInfo> responseEntity = restTemplate.getForEntity(url, EnvInfo.class);
System.out.println("statusCode: " + responseEntity.getStatusCode().toString());
System.out.println("statusCodeValue: " + responseEntity.getStatusCodeValue());
responseEntity.getHeaders().forEach((key, values) -> {
System.out.println(key + ": " + values);
});输出结果：
statusCode: 200
statusCodeValue: 200
Server: [openresty]
Date: [Thu, 10 Apr 2025 05:39:02 GMT]
Content-Type: [application/json]
Transfer-Encoding: [chunked]
Connection: [keep-alive]
其中Response Headers输出部分和Chrome浏览器Network中的Response Headers是一致的：
2.6 发送GET请求(带参数及请求头)
一般情况下，请求第三方接口都需要签名、时间戳等请求头，但getForObject()和getForEntity()都不支持，
此时需要使用exchange()方法，代码如下所示：
RestTemplate restTemplate = new RestTemplate();
String httpUrl = "https://www.example.com/getDataList";
UriComponentsBuilder uriComponentsBuilder = UriComponentsBuilder.fromHttpUrl(httpUrl);
uriComponentsBuilder.queryParam("pageIndex", 1);
uriComponentsBuilder.queryParam("pageSize", 20);
HttpHeaders headers = new HttpHeaders();
headers.set("signature", "3045022100875efcef9eb54626bb0168a6baa7c61265d0001d49243f");
headers.set("timestamp", String.valueOf(System.currentTimeMillis()));
String url = uriComponentsBuilder.toUriString();
ResponseEntity<EnvInfo> responseEntity = restTemplate.exchange(url,
HttpMethod.GET,
new HttpEntity<>(headers),
EnvInfo.class);
if (responseEntity.getStatusCode() == HttpStatus.OK) {
EnvInfo response = responseEntity.getBody();
System.out.println(JSON.toJSONString(response));
}3. 发送POST请求
使用RestTemplate发送POST请求主要有postForObject()和postForEntity()2个方法，每个方法分别提供了3种不同的重载。
3.1 发送POST请求(带参数、json方式)
使用postForObject()实现：
RestTemplate restTemplate = new RestTemplate();
HttpHeaders headers = new HttpHeaders();
headers.setContentType(MediaType.APPLICATION_JSON_UTF8);
LoginParams loginParams = new LoginParams();
loginParams.setUsername("zhangsan");
loginParams.setPassword("123456");
HttpEntity<LoginParams> request = new HttpEntity<>(loginParams, headers);
String url = "https://www.example.com/login";
String response = restTemplate.postForObject(url, request, String.class);
System.out.println(response);LoginParams的定义如下所示：
import lombok.Getter;
import lombok.Setter;
@Getter
@Setter
public class LoginParams {
private String username;
private String password;
}假设以上接口返回的报文为：
{
"code": 200,
"expire": "2025-04-11 14:42:22",
"token": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJleHAiOjE3NDQzNTM3NDIsImlkZW50aXR5"
}也可以直接解析为自定义的类型：
import lombok.Getter;
import lombok.Setter;
@Getter
@Setter
public class LoginResponse {
private Integer code;
private String expire;
private String token;
}RestTemplate restTemplate = new RestTemplate();
HttpHeaders headers = new HttpHeaders();
headers.setContentType(MediaType.APPLICATION_JSON_UTF8);
LoginParams loginParams = new LoginParams();
loginParams.setUsername("zhangsan");
loginParams.setPassword("123456");
HttpEntity<LoginParams> request = new HttpEntity<>(loginParams, headers);
String url = "https://www.example.com/login";
LoginResponse response = restTemplate.postForObject(url, request, LoginResponse.class);
System.out.println(JSON.toJSONString(response));也可以使用postForEntity()实现同样的功能，代码如下所示：
ResponseEntity<LoginResponse> responseEntity = restTemplate.postForEntity(url, request, LoginResponse.class);
if (responseEntity.getStatusCode() == HttpStatus.OK) {
LoginResponse response = responseEntity.getBody();
System.out.println(JSON.toJSONString(response));
}3.2 发送POST请求(带参数、form表单方式)
使用postForObject()实现：
RestTemplate restTemplate = new RestTemplate();
HttpHeaders headers = new HttpHeaders();
headers.setContentType(MediaType.APPLICATION_FORM_URLENCODED);
MultiValueMap<String, String> map = new LinkedMultiValueMap<>();
map.add("username", "zhangsan");
map.add("password", "123456");
HttpEntity<MultiValueMap<String, String>> request = new HttpEntity<>(map, headers);
String url = "https://www.example.com/login";
LoginResponse response = restTemplate.postForObject(url, request, LoginResponse.class);
System.out.println(JSON.toJSONString(response));也可以使用postForEntity()实现同样的功能，代码如下所示：
ResponseEntity<LoginResponse> responseEntity = restTemplate.postForEntity(url, request, LoginResponse.class);
if (responseEntity.getStatusCode() == HttpStatus.OK) {
LoginResponse response = responseEntity.getBody();
System.out.println(JSON.toJSONString(response));
}3.3 postForObject与postForEntity的区别
postForObject()与postForEntity()的区别，与getForEntity()与getForObject()的区别一样，
返回值用了ResponseEntity进行封装。
4. 超时时间设置
如果需要自定义HTTP请求的连接超时时间和数据传输超时时间，代码如下所示：
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.client.SimpleClientHttpRequestFactory;
import org.springframework.web.client.RestTemplate;
@Configuration
public class RestTemplateConfig {
@Value("${restTemplate.connectTimeout:5000}")
private int connectTimeout;
@Value("${restTemplate.readTimeout:10000}")
private int readTimeout;
@Bean
public RestTemplate restTemplate() {
SimpleClientHttpRequestFactory simpleClientHttpRequestFactory = new SimpleClientHttpRequestFactory();
simpleClientHttpRequestFactory.setConnectTimeout(connectTimeout);
simpleClientHttpRequestFactory.setReadTimeout(readTimeout);
return new RestTemplate(simpleClientHttpRequestFactory);
}
}到此这篇关于Spring RestTemplate使用方法总结的文章就介绍到这了,更多相关Spring RestTemplate使用内容请搜索脚本之家以前的文章或继续浏览下面的相关文章希望大家以后多多支持脚本之家！
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