我必须进行REST调用,其中包括自定义头和查询参数。我设置我的HttpEntity只有头(没有正文),我使用RestTemplate.exchange()方法如下:

HttpHeaders headers = new HttpHeaders();
headers.set("Accept", "application/json");

Map<String, String> params = new HashMap<String, String>();
params.put("msisdn", msisdn);
params.put("email", email);
params.put("clientVersion", clientVersion);
params.put("clientType", clientType);
params.put("issuerName", issuerName);
params.put("applicationName", applicationName);

HttpEntity entity = new HttpEntity(headers);

HttpEntity<String> response = restTemplate.exchange(url, HttpMethod.GET, entity, String.class, params);

这在客户端失败,因为调度程序servlet无法将请求解析到处理程序。调试之后,似乎没有发送请求参数。

当我使用请求体和没有查询参数的POST做一个交换时,它工作得很好。

有人有什么想法吗?


当前回答

在Spring Web 4.3.6中我也看到了

public <T> T getForObject(String url, Class<T> responseType, Object... uriVariables)

这意味着你不必创建一个丑陋的地图

如果你有这个url

http://my-url/action?param1={param1}&param2={param2}

你可以选择

restTemplate.getForObject(url, Response.class, param1, param2)

or

restTemplate.getForObject(url, Response.class, param [])

其他回答

还有一个解决方法:

private String execute(String url, Map<String, String> params) {
    UriComponentsBuilder uriBuilder = UriComponentsBuilder.fromUriString(url)
    // predefined params
            .queryParam("user", "userValue")
            .queryParam("password", "passwordValue");
    params.forEach(uriBuilder::queryParam);
    HttpHeaders headers = new HttpHeaders() {{
        setContentType(MediaType.APPLICATION_FORM_URLENCODED);
        setAccept(List.of(MediaType.APPLICATION_JSON));
    }};
    ResponseEntity<String> request = restTemplate.exchange(uriBuilder.toUriString(), 
                HttpMethod.GET, new HttpEntity<>(headers), String.class);
    return request.getBody();

}

在Spring Web 4.3.6中我也看到了

public <T> T getForObject(String url, Class<T> responseType, Object... uriVariables)

这意味着你不必创建一个丑陋的地图

如果你有这个url

http://my-url/action?param1={param1}&param2={param2}

你可以选择

restTemplate.getForObject(url, Response.class, param1, param2)

or

restTemplate.getForObject(url, Response.class, param [])

我也尝试过类似的东西,RoboSpice的例子帮助我解决了这个问题:

HttpHeaders headers = new HttpHeaders();
headers.set("Accept", "application/json");

HttpEntity<String> request = new HttpEntity<>(input, createHeader());

String url = "http://awesomesite.org";
Uri.Builder uriBuilder = Uri.parse(url).buildUpon();
uriBuilder.appendQueryParameter(key, value);
uriBuilder.appendQueryParameter(key, value);
...

String url = uriBuilder.build().toString();

HttpEntity<String> response = restTemplate.exchange(url, HttpMethod.GET, request , String.class);

将哈希映射转换为查询参数字符串:

Map<String, String> params = new HashMap<>();
params.put("msisdn", msisdn);
params.put("email", email);
params.put("clientVersion", clientVersion);
params.put("clientType", clientType);
params.put("issuerName", issuerName);
params.put("applicationName", applicationName);

UriComponentsBuilder builder = UriComponentsBuilder.fromHttpUrl(url);
for (Map.Entry<String, String> entry : params.entrySet()) {
    builder.queryParam(entry.getKey(), entry.getValue());
}

HttpHeaders headers = new HttpHeaders();
headers.set("Accept", "application/json");

HttpEntity<String> response = restTemplate.exchange(builder.toUriString(), HttpMethod.GET, new HttpEntity(headers), String.class);

我真是个白痴,我把查询参数和url参数搞混了。我有点希望有一个更好的方式来填充我的查询参数,而不是一个丑陋的连接字符串,但我们有。这只是一个用正确的参数构建URL的例子。如果你把它作为一个字符串传递,Spring也会为你处理编码。