我提供了一个RestTemplate GET方法的代码片段与路径参数示例

public ResponseEntity<String> getName(int id) {
    final String url = "http://localhost:8080/springrestexample/employee/name?id={id}";
    Map<String, String> params = new HashMap<String, String>();
    params.put("id", id);
    HttpHeaders headers = new HttpHeaders();
    headers.setContentType(MediaType.APPLICATION_JSON);
    HttpEntity request = new HttpEntity(headers);
    ResponseEntity<String> response = restTemplate.exchange(url, HttpMethod.GET, String.class, params);
    return response;
}

    String uri = http://my-rest-url.org/rest/account/{account};

    Map<String, String> uriParam = new HashMap<>();
    uriParam.put("account", "my_account");

    UriComponents builder = UriComponentsBuilder.fromHttpUrl(uri)
                .queryParam("pageSize","2")
                        .queryParam("page","0")
                        .queryParam("name","my_name").build();

    HttpEntity<String> requestEntity = new HttpEntity<>(null, getHeaders());

    ResponseEntity<String> strResponse = restTemplate.exchange(builder.toUriString(),HttpMethod.GET, requestEntity,
                        String.class,uriParam);

    //final URL: http://my-rest-url.org/rest/account/my_account?pageSize=2&page=0&name=my_name

RestTemplate:使用UriComponents (URI变量和请求参数)构建动态URI

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);

public static void main(String[] args) {
         HttpHeaders httpHeaders = new HttpHeaders();
         httpHeaders.set("Accept", MediaType.APPLICATION_JSON_VALUE);
         final String url = "https://host:port/contract/{code}";
         Map<String, String> params = new HashMap<String, String>();
         params.put("code", "123456");
         HttpEntity<?> httpEntity  = new HttpEntity<>(httpHeaders); 
         RestTemplate restTemplate  = new RestTemplate();
         restTemplate.exchange(url, HttpMethod.GET, httpEntity,String.class, params);
    }

可以对String使用follow代码。

URL_EXAMPLE="http://{domain}/Index.php?Username={user}&password={password}";

String domain = "example.com";
String user = "user";
String password = "password";

String data=this.restTemplate.getForObject(URL_EXAMPLE,String.class,domain,user,password);

至少从Spring 3开始，许多RestTemplate方法不是使用UriComponentsBuilder来构建URL(这有点啰嗦)，而是在参数路径中接受占位符(不仅仅是交换)。

从文档中可以看到:

Many of the RestTemplate methods accepts a URI template and URI template variables, either as a String vararg, or as Map<String,String>. For example with a String vararg: restTemplate.getForObject( "http://example.com/hotels/{hotel}/rooms/{room}", String.class, "42", "21"); Or with a Map<String, String>: Map<String, String> vars = new HashMap<>(); vars.put("hotel", "42"); vars.put("room", "21"); restTemplate.getForObject("http://example.com/hotels/{hotel}/rooms/{room}", String.class, vars);

参考:https://docs.spring.io/spring/docs/current/spring-framework-reference/integration.html # rest-resttemplate-uri

如果你查看JavaDoc for RestTemplate并搜索“URI Template”，你可以看到哪些方法可以使用占位符。