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Java

SharePoint OAuth2 Client Credentials Authentication

Demonstrates how to authenticate with OAuth 2.0 using the client credentials grant type. This is for SharePoint Online which is the cloud-based service provided by Microsoft as part of Office 365. (Users access SharePoint Online through a web browser, and the service is hosted on Microsoft's servers.)

Chilkat Java Downloads

Java
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[])
  {
    boolean success = false;

    // This requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    CkHttp http = new CkHttp();

    // Provide the information needed for Chilkat to automatically fetch the OAuth2.0 
    // access token as needed.
    CkJsonObject jsonOAuthCC = new CkJsonObject();

    // --------------------------------------------------------------------------------------------------------
    // You'll need to have registered an app in Azure beforehand.
    // See How to Create SharePoint App Registration for OAuth 2.0 Client Credentials
    // --------------------------------------------------------------------------------------------------------

    // Use the values from your App Registration in Azure.
    jsonOAuthCC.UpdateString("client_id","CLIENT_ID");
    jsonOAuthCC.UpdateString("client_secret","SECRET_VALUE");

    // You'll always use this scope for client credentials, because the allowed actions
    // are determined by the App Permissions defined when you registered the app in Azure.
    jsonOAuthCC.UpdateString("scope","https://graph.microsoft.com/.default");

    // The token endpoint includes your tenant ID. 
    jsonOAuthCC.UpdateString("token_endpoint","https://login.microsoftonline.com/TENANT_ID/oauth2/v2.0/token");

    // Provide the OAuth2 information. Chilkat will use this information to automatically fetch the OAuth2 access token as needed,
    http.put_AuthToken(jsonOAuthCC.emit());

    // Get information about all SharePoint sites.
    CkStringBuilder sbJson = new CkStringBuilder();
    success = http.QuickGetSb("https://graph.microsoft.com/v1.0/sites/getAllSites",sbJson);
    if (success == false) {
        System.out.println(http.lastErrorText());
        return;
        }

    int statusCode = http.get_LastStatus();

    System.out.println("Response status code = " + statusCode);

    if (statusCode != 200) {
        System.out.println(sbJson.getAsString());
        System.out.println("Failed.");
        return;
        }

    CkJsonObject jsonResp = new CkJsonObject();
    jsonResp.LoadSb(sbJson);
    jsonResp.put_EmitCompact(false);

    System.out.println(jsonResp.emit());
    System.out.println("Success.");

    // Use this online tool to generate parsing code from sample JSON: 
    // Generate Parsing Code from JSON
  }
}