Client applications

Instantiate an application

Pre-requisites

Before instantiating your app with MSAL4J:

1. Understand the types of Client applications available- Public Client and Confidential Client applications.
2. You'll need to register the application with Microsoft Entra ID. You will therefore know:
   • Its clientID (a string representing a GUID)
   • The identity provider URL (named the instance) and the sign-in audience for your application. These two parameters are collectively known as the authority.
   • Possibly the TenantID in the case you are writing a line of business application (just for your organization, also named single-tenant application)
   • In case it's a confidential client app, its application secret (clientSecret string) or certificate
   • For web apps, you'll have also set the redirectUri where the identity provider will contact back your application with the security tokens.

Instantiate a Public Client application

String PUBLIC_CLIENT_ID;
String AUTHORITY;

PublicClientApplication app = 
    PublicClientApplication
        .builder(PUBLIC_CLIENT_ID)
        .authority(AUTHORITY)
        .build();

Instantiate a Confidential Client application

You will need either a secret or a certificate, as described in Client Credentials.

If you have a secret:

String PUBLIC_CLIENT_ID;
String AUTHORITY;
String CLIENT_SECRET;

IClientCredential credential = ClientCredentialFactory.createFromSecret(CLIENT_SECRET);
ConfidentialClientApplication app = 
    ConfidentialClientApplication
        .builder(PUBLIC_CLIENT_ID, credential)
        .authority(AUTHORITY)
        .build();

If you have a certificate:

String PUBLIC_CLIENT_ID;
String AUTHORITY;
PrivateKey PRIVATE_KEY;  
X509Certificate PUBLIC_KEY;

IClientCredential credential = ClientCredentialFactory.createFromCertificate(PRIVATE_KEY, PUBLIC_KEY);
ConfidentialClientApplication app = 
    ConfidentialClientApplication
        .builder(PUBLIC_CLIENT_ID, credential)
        .authority(AUTHORITY)
        .build();