在Java请求中使用$ filter参数以动态CRM时的400状态代码

Question

I'm trying query data from dynamics CRM through java HttpUrlConnection object. I always get an HTTP 400 status code when my request include the $filter parameter. But when I remove this parameter my request works fine. I have tried my request directly on a browser and it works fine too. The code below shows how I built my request

public String getContactByPhoneNumber(String phoneNumber) throws Exception {
    HttpURLConnection connection = null;
    URL url = new URL(completeURL + "/contacts?select=lastname&$filter=telephone1 eq '"+phoneNumber+"'");
    connection = (HttpURLConnection) url.openConnection();
    connection.setRequestMethod("GET");
    connection.setRequestProperty("OData-MaxVersion", "4.0");
    connection.setRequestProperty("OData-Version", "4.0");
    connection.setRequestProperty("Accept", "application/json");
    connection.setRequestProperty("Prefer", "odata.include-annotations=\"*\"");
    connection.setRequestProperty("Content-Type", "application/json; charset=utf-8");
    connection.addRequestProperty("Authorization", "Bearer " + token);
    if (connection.getResponseCode() == 200) {
        String response = getResponseAsString(connection);
        return response;
    } else {
        String error = getErrorAsString(connection);
        System.err.println(error);
        return null;
    }

}

Did anyone met this error? How can I solve it?

Answer 1

I haven't tested this myself, so I can't guarantee that it works, but you could try URL-encoding the $filter parameter name and its value:

import java.net.URLEncoder;

// ... 

  URL url = new URL(
    completeURL + "/contacts?select=lastname&"
    + URLEncoder.encode("$filter", "UTF-8") + "="
    + URLEncoder.encode("telephone1 eq '"+phoneNumber+"'", "UTF-8"));

Answer 2

Luke mentioned you had misspelled "filter" in your original text. That may have something to do with it if it was not just a typo here in your post.

Also, "$" is a reserved character in URI syntax according to RFC 2396. http://www.faqs.org/rfcs/rfc2396.html

2.2. Reserved Characters

 Many URI include components consisting of or delimited by, certain
special characters.  These characters are called "reserved", since
their usage within the URI component is limited to their reserved
purpose.  If the data for a URI component would conflict with the
reserved purpose, then the conflicting data must be escaped before
forming the URI.

  reserved    = ";" | "/" | "?" | ":" | "@" | "&" | "=" | "+" |
                "$" | ","

The "reserved" syntax class above refers to those characters that are
allowed within a URI, but which may not be allowed within a
particular component of the generic URI syntax; they are used as
delimiters of the components described in Section 3.

Characters in the "reserved" set are not reserved in all contexts.
The set of characters actually reserved within any given URI
component is defined by that component. In general, a character is
reserved if the semantics of the URI changes if the character is
replaced with its escaped US-ASCII encoding.

You could try to form the URL without it and see if that works.