RestTemplate的使用

RestTemplate是Spring提供的用于访问Rest服务的客户端，RestTemplate提供了多种便捷访问远程Http服务的方法,能够大大提高客户端的编写效率。

1、写配置项

import org.springframework.boot.web.client.RestTemplateBuilder;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.client.RestTemplate;

@Configuration
public class WebMvcConfig {
    @Bean
    public RestTemplate restTemplate(RestTemplateBuilder builder) {
        return builder.build();
    }
}

2、注入

 @Autowired
    private RestTemplate restTemplate;

3、使用

     MerchantOrdersVO merchantOrdersVO = new MerchantOrdersVO();
        merchantOrdersVO.setReturnUrl(payReturnUrl);
        HttpHeaders headers = new HttpHeaders();
        headers.setContentType(MediaType.APPLICATION_JSON);
        headers.add("imoocUserId", "imooc");
        headers.add("password", "imooc");
        HttpEntity<MerchantOrdersVO> entity = new HttpEntity<>(merchantOrdersVO, headers);
        ResponseEntity<IMOOCJSONResult> responseEntity
                = restTemplate.postForEntity(paymentUrl, entity, IMOOCJSONResult.class); // paymentUrl要访问的url,IMOOCResult.class返回值类型
        IMOOCJSONResult paymentResult = responseEntity.getBody();
        if(paymentResult.getStatus() != 200){
            return IMOOCJSONResult.errorMsg("支付中心订单创建失败，请联系管理员");
        }
        return IMOOCJSONResult.ok(orderVO.getOrderId());