resttemplate调用

Map<String, Object> queryForHttp(String url, Map<String, Object> header, Map<String, Object> param, HttpMethod method) throws Exception{
    // 默认使用Get方法查询
    if (method == null)
        method = HttpMethod.GET;
    HttpHeaders headers = new HttpHeaders();
    //设置默认为短连接
    headers.add("Connection", "close");
    if (!CollectionUtils.isEmpty(header)) {
        for (String key : header.keySet()) {
            headers.add(key, header.get(key).toString());
        }
    }
    HttpEntity request = new HttpEntity<>(param, headers);

    ResponseEntity<HashMap> exchange = restTemplate.exchange(url, method, request, HashMap.class);
    HashMap result = null;
    if (exchange != null && exchange.getBody() != null) {
        result = exchange.getBody();
    }
    return result;
}