restTemplate get请求传body

一、jari包

<dependency>
    <groupId>org.apache.httpcomponents</groupId>
    <artifactId>httpclient</artifactId>
    <version>4.5.2</version>
</dependency>

二、定义HttpComponentsClientRestfulHttpRequestFactory

import org.apache.http.client.methods.HttpEntityEnclosingRequestBase;
import org.apache.http.client.methods.HttpUriRequest;
import org.springframework.http.HttpMethod;
import org.springframework.http.client.HttpComponentsClientHttpRequestFactory;

import java.net.URI;

public class HttpComponentsClientRestfulHttpRequestFactory extends HttpComponentsClientHttpRequestFactory {

    @Override
    protected HttpUriRequest createHttpUriRequest(HttpMethod httpMethod, URI uri) {
        if (httpMethod == HttpMethod.GET) {
            return new HttpGetRequestWithEntity(uri);
        }
        return super.createHttpUriRequest(httpMethod, uri);
    }
    //核心代码
    private static final class HttpGetRequestWithEntity extends HttpEntityEnclosingRequestBase {
        public HttpGetRequestWithEntity(final URI uri) {
            super.setURI(uri);
        }

        @Override
        public String getMethod() {
            return HttpMethod.GET.name();
        }
    }

}

三、使用

RestTemplate restTemplate = new RestTemplate();
//修改restTemplate的RequestFactory使其支持Get携带body参数
restTemplate.setRequestFactory(new HttpComponentsClientRestfulHttpRequestFactory());

HttpHeaders headers = new HttpHeaders();
headers.setContentType(MediaType.APPLICATION_JSON);
Map map= new HashMap();
map.put("param", 123);
HttpEntity<String> httpEntity = new HttpEntity<>(JSON.toJSONString(map), headers);

ResponseEntity<String> exchange = restTemplate.exchange("your url", HttpMethod.GET, httpEntity, String.class);