Set Up Authorization with OAuth 2.0

1public static void oAuthSessionProvider(String loginHost, String username,
2        String password, String clientId, String secret)
3        throws HttpException, IOException 
4{
5    // Set up an HTTP client that makes a connection to REST API.
6    DefaultHttpClient client = new DefaultHttpClient();
7    HttpParams params = client.getParams();
8    HttpClientParams.setCookiePolicy(params, CookiePolicy.RFC_2109);
9    params.setParameter(HttpConnectionParams.CONNECTION_TIMEOUT, 30000);
10
11    // Set the SID.
12    System.out.println("Logging in as " + username + " in environment " + loginHost);
13    String baseUrl = loginHost + "/services/oauth2/token";
14    // Send a post request to the OAuth URL.
15    HttpPost oauthPost = new HttpPost(baseUrl);
16    // The request body must contain these 5 values.
17    List<BasicNameValuePair> parametersBody = new ArrayList<BasicNameValuePair>();
18    parametersBody.add(new BasicNameValuePair("grant_type", "password"));
19    parametersBody.add(new BasicNameValuePair("username", username));
20    parametersBody.add(new BasicNameValuePair("password", password));
21    parametersBody.add(new BasicNameValuePair("client_id", clientId));
22    parametersBody.add(new BasicNameValuePair("client_secret", secret));
23    oauthPost.setEntity(new UrlEncodedFormEntity(parametersBody, HTTP.UTF_8));
24
25    // Execute the request.
26    System.out.println("POST " + baseUrl + "...\n");
27    HttpResponse response = client.execute(oauthPost);
28    int code = response.getStatusLine().getStatusCode();
29    Map<String, String> oauthLoginResponse = (Map<String, String>)
30        JSON.parse(EntityUtils.toString(response.getEntity()));
31    System.out.println("OAuth login response");
32    for (Map.Entry<String, String> entry : oauthLoginResponse.entrySet()) 
33    {
34        System.out.println(String.format("  %s = %s", entry.getKey(), entry.getValue()));
35    }
36    System.out.println("");
37
38    // Get user info.
39    String userIdEndpoint = oauthLoginResponse.get("id");
40    String accessToken = oauthLoginResponse.get("access_token");
41    List<BasicNameValuePair> qsList = new ArrayList<BasicNameValuePair>();
42    qsList.add(new BasicNameValuePair("oauth_token", accessToken));
43    String queryString = URLEncodedUtils.format(qsList, HTTP.UTF_8);
44    HttpGet userInfoRequest = new HttpGet(userIdEndpoint + "?" + queryString);
45    HttpResponse userInfoResponse = client.execute(userInfoRequest);
46    Map<String, Object> userInfo = (Map<String, Object>)
47        JSON.parse(EntityUtils.toString(userInfoResponse.getEntity()));
48    System.out.println("User info response");
49    for (Map.Entry<String, Object> entry : userInfo.entrySet()) 
50    {
51        System.out.println(String.format("  %s = %s", entry.getKey(), entry.getValue()));
52    }
53    System.out.println("");
54
55    // Use the user info in interesting ways.
56    System.out.println("Username is " + userInfo.get("username"));
57    System.out.println("User's email is " + userInfo.get("email"));
58    Map<String, String> urls = (Map<String, String>)userInfo.get("urls");
59    System.out.println("REST API url is " + urls.get("rest").replace("{version}", "53.0"));
60}