(Java) Dropbox Refresh OAuth2 Access Token

See more Dropbox Examples

Demonstrates how to mint a new access token using the refresh token obtained when originally getting the OAuth2 access token.

For more information, see https://www.dropbox.com/developers/documentation/http/documentation

Chilkat Java Downloads Java Libs for Windows, MacOS, Linux, Alpine Linux, Solaris Java Libs for Android

import com.chilkatsoft.*;

public class ChilkatExample {

  static {
    try {
        System.loadLibrary("chilkat");
    } catch (UnsatisfiedLinkError e) {
      System.err.println("Native code library failed to load.\n" + e);
      System.exit(1);
    }
  }

  public static void main(String argv[])
  {
    // This example assumes the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    CkHttp http = new CkHttp();
    boolean success;

    // Implements the following CURL command:

    // curl -X GET https://api.dropbox.com/oauth2/token \
    //     -d grant_type=refresh_token \
    //     -d refresh_token=<YOUR_REFRESH_TOKEN> \
    //     -u <YOUR_APP_KEY>:<YOUR_APP_SECRET>

    // Use the following online tool to generate HTTP code from a CURL command
    // Convert a cURL Command to HTTP Source Code

    http.put_Login("DROPBOX_APP_KEY");
    http.put_Password("DROPBOX_APP_SECRET");

    // Get the refresh token from the JSON we saved when originally getting the access token.
    // (See Get Dropbox OAuth2 Access Token w/ Refresh Token
    CkJsonObject json = new CkJsonObject();
    success = json.LoadFile("qa_data/tokens/dropbox.json");
    if (success == false) {
        System.out.println(json.lastErrorText());
        return;
        }

    CkHttpRequest req = new CkHttpRequest();
    req.AddParam("grant_type","refresh_token");
    req.AddParam("refresh_token",json.stringOf("refresh_token"));

    CkHttpResponse resp = http.PostUrlEncoded("https://api.dropbox.com/oauth2/token",req);
    if (http.get_LastMethodSuccess() == false) {
        System.out.println(http.lastErrorText());
        return;
        }

    CkStringBuilder sbResponseBody = new CkStringBuilder();
    resp.GetBodySb(sbResponseBody);

    CkJsonObject jResp = new CkJsonObject();
    jResp.LoadSb(sbResponseBody);
    jResp.put_EmitCompact(false);

    System.out.println("Response Body:");
    System.out.println(jResp.emit());

    int respStatusCode = resp.get_StatusCode();
    System.out.println("Response Status Code = " + respStatusCode);
    if (respStatusCode >= 400) {
        System.out.println("Response Header:");
        System.out.println(resp.header());
        System.out.println("Failed.");

        return;
        }

    // Sample JSON response:
    // (Sample code for parsing the JSON response is shown below)

    // {
    //   "access_token": "sl.AC75WPYRqOi0mxcRqlimbV9FKHu04biz5qHwatG3MTgzFK7kLrGVlM9EgP4603tE7bWw0s1rMbTKiHsf37TUshPYvq-3r0qeBr_PrZIAibN8XOQicvboiOnqx6JrDekq-w8D-tE",
    //   "token_type": "bearer",
    //   "expires_in": 14400
    // }

    String access_token = jResp.stringOf("access_token");
    System.out.println("New Access Token: " + access_token);

    // Perhaps update our Dropbox JSON file with the new access token.
    // (The existing refresh token does not change, and can be used over and over to mint new access tokens.)
    json.UpdateString("access_token",access_token);

    json.WriteFile("qa_data/tokens/dropbox.json");
  }
}