Question

我正在尝试使用Apache HttpClient从站点的API获取JSON响应，但是它给了我一个“IllegalStateException：目标主机不能为null，或者在参数中设置。”

Java代码：

private String orderInURL = "https://r-test.ordr.in";

public String deliveryList(String datetime, String zip, String city, String addr) throws ClientProtocolException, IOException {
    String listURL = orderInURL+"/dl/" + datetime + "/" + zip + "/" + city + "/" + 
                addr + "?_auth=1," + this.privateKey;
    DefaultHttpClient httpClient = new DefaultHttpClient();
    HttpGet getRequest = new HttpGet(URLEncoder.encode(listURL, "UTF-8"));

    //header
    getRequest.setHeader("accept", "application/json");

    HttpResponse response = httpClient.execute(getRequest);

    if (response.getStatusLine().getStatusCode() != 200) {
        throw new RuntimeException("Failed : HTTP error code : "
           + response.getStatusLine().getStatusCode());
    }

    BufferedReader br = new BufferedReader(
            new InputStreamReader((response.getEntity().getContent())));

    String output;
    System.out.println("Output from Server .... \n");
    while ((output = br.readLine()) != null) {
        System.out.println(output);
    }

    httpClient.getConnectionManager().shutdown();
    return output;
}


 ....
 System.out.println(orderin.deliveryList("ASAP", "11111", "MyCity", "100 My Address"));

GET网址原为：

https://r-test.ordr.in/dl/ASAP/11111/MyCity/100%20My%20Address?_auth=1,XXXXXXXXXXXXXXXXX

如果用私钥替换XXXXXXXXX ....如果我只是复制了这个URL并将其放入浏览器中，那么返回正确的JSON。我不知道为什么它不能在Java中返回正确的结果。任何帮助表示赞赏。

Answer 1

不确定问题是什么，但有一种更简单的方法从URL读取JSON。尝试这样的事情：

public static String readJsonFromUrl(String url) throws IOException
{
    InputStream is = new URL(url).openStream();
    try {
      BufferedReader rd = new BufferedReader(
              new InputStreamReader(is, Charset.forName("UTF-8")));
      String jsonText = readAll(rd);
      return jsonText;
    } finally {
      is.close();
    }
    return "";
}

private static String readAll(Reader rd) throws IOException 
{
    StringBuilder sb = new StringBuilder();
    int cp;
    while ((cp = rd.read()) != -1) {
      sb.append((char) cp);
    }
    return sb.toString();
}

Answer 2

rfc2616要求HTTP 1.1服务器在没有主机标头的情况下拒绝HTTP请求，请参阅rfc2616第14.23节。在调用httpClient.execute之前尝试添加以下行：

getRequest.setHeader("host", "r-test.ordr.in");

Apache HttpClient错误：目标主机不能为空，或者在参数中设置

2 个答案: