ADAL to MSAL migration guide for Java

Artigo
01/27/2024

This article highlights changes you need to make to migrate an application that uses the Azure Active Directory Authentication Library (ADAL) to the Microsoft Authentication Library (MSAL).

Both the Microsoft Authentication Library for Java (MSAL4J) and Azure AD Authentication Library for Java (ADAL4J) are used to authenticate Microsoft Entra entities and request tokens from Microsoft Entra ID. Until now, most developers have worked with Azure AD for developers (v1.0) to authenticate with various identities, such as work and school accounts, by requesting tokens using Azure AD Authentication Library (ADAL).

MSAL offers the following benefits:

Because it uses the newer Microsoft identity platform, you can authenticate a broader set of Microsoft identities such as Microsoft Entra identities, Microsoft accounts, social and local accounts through Azure AD Business to Consumer (Azure AD B2C), and social or local customer accounts through Microsoft Entra External ID.
Your users will get the best single-sign-on experience.
Your application can enable incremental consent, as well as support new features, such as Conditional Access.

MSAL for Java is the authentication library we recommend you use with the Microsoft identity platform. No new features will be implemented on ADAL4J. All efforts going forward are focused on improving MSAL.

You can learn more about MSAL and get started with an overview of the Microsoft Authentication Library.

Scopes not resources

ADAL4J acquires tokens for resources whereas MSAL for Java acquires tokens for scopes. Many MSAL for Java classes require a scopes parameter. This parameter is a list of strings that declare the desired permissions and resources that are requested. See Microsoft Graph's scopes to see example scopes.

You can add the /.default scope suffix to the resource to help migrate your apps from the ADAL to MSAL. For example, for the resource value of https://graph.microsoft.com, the equivalent scope value is https://graph.microsoft.com/.default. If the resource isn't in the URL form, but a resource ID of the form XXXXXXXX-XXXX-XXXX-XXXXXXXXXXXX, you can still use the scope value as XXXXXXXX-XXXX-XXXX-XXXXXXXXXXXX/.default.

For more details about the different types of scopes, refer Permissions and consent in the Microsoft identity platform and the Scopes for a Web API accepting v1.0 tokens articles.

Core classes

In ADAL4J, the AuthenticationContext class represents your connection to the Security Token Service (STS), or authorization server, through an Authority. However, MSAL for Java is designed around client applications. It provides two separate classes: PublicClientApplication and ConfidentialClientApplication to represent client applications. The latter, ConfidentialClientApplication, represents an application that is designed to securely maintain a secret such as an application identifier for a daemon app.

The following table shows how ADAL4J functions map to the new MSAL for Java functions:

ADAL4J method	MSAL4J method
acquireToken(String resource, ClientCredential credential, AuthenticationCallback callback)	ClientCredentialParameters
acquireToken(String resource, ClientAssertion assertion, AuthenticationCallback callback)	ClientCredentialParameters
acquireToken(String resource, AsymmetricKeyCredential credential, AuthenticationCallback callback)	ClientCredentialParameters
acquireToken(String resource, String clientId, String username, String password, AuthenticationCallback callback)	UserNamePasswordParameters
acquireToken(String resource, String clientId, String username, String password=null, AuthenticationCallback callback)	IntegratedWindowsAuthenticationParameters
acquireToken(String resource, UserAssertion userAssertion, ClientCredential credential, AuthenticationCallback callback)	OnBehalfOfParameters
acquireTokenByAuthorizationCode()	AuthorizationCodeParameters
acquireDeviceCode() and acquireTokenByDeviceCode()	DeviceCodeFlowParameters
acquireTokenByRefreshToken()	SilentParameters

IAccount instead of IUser

ADAL4J handled users. Although a user represents a single human or software agent, it can have one or more accounts in the Microsoft identity system. For example, a user may have several Microsoft Entra ID, Azure AD B2C, or Microsoft personal accounts.

MSAL for Java defines the concept of Account via the IAccount interface. This is a breaking change from ADAL4J. It captures the fact that the same user can have several accounts, and perhaps even in different Microsoft Entra directories. MSAL for Java provides better information in guest scenarios because home account information is provided.

Cache persistence

ADAL4J didn't have support for token cache. MSAL for Java adds a token cache to simplify managing token lifetimes by automatically refreshing expired tokens when possible and preventing unnecessary prompts for the user to provide credentials when possible.

Common Authority

In v1.0, if you use the https://login.microsoftonline.com/common authority, users can sign in with any Microsoft Entra account (for any organization).

If you use the https://login.microsoftonline.com/common authority in v2.0, users can sign in with any Microsoft Entra organization, or even a Microsoft personal account (MSA). In MSAL for Java, if you want to restrict login to any Microsoft Entra account, use the https://login.microsoftonline.com/organizations authority (which is the same behavior as with ADAL4J). To specify an authority, set the authority parameter in the PublicClientApplication.Builder method when you instantiate a PublicClientApplication class.

v1.0 and v2.0 tokens

The v1.0 endpoint (used by ADAL) only emits v1.0 tokens.

The v2.0 endpoint (used by MSAL) can emit v1.0 and v2.0 tokens. A property of the application manifest of the web API enables developers to choose which version of token is accepted. See accessTokenAcceptedVersion in the application manifest reference documentation.

For more information about v1.0 and v2.0 tokens, see Microsoft Entra access tokens.

ADAL to MSAL migration

In ADAL4J, the refresh tokens were exposed--which allowed developers to cache them. They would then use AcquireTokenByRefreshToken() to enable solutions such as implementing long-running services that refresh dashboards on behalf of the user when the user is no longer connected.

MSAL for Java doesn't expose refresh tokens for security reasons. Instead, MSAL handles refreshing tokens for you.

MSAL for Java has an API that allows you to migrate refresh tokens acquired with ADAL4J into the ClientApplication: RefreshTokenParameters. With this method, you can provide the previously used refresh token along with any scopes (resources) you desire. The refresh token will be exchanged for a new one and cached for use by your application.

The following code snippet shows a simple migration code snippet in a confidential client application:

String rt = GetCachedRefreshTokenForSignedInUser(); // Get refresh token from where you have them stored
Set<String> scopes = Collections.singleton("SCOPE_FOR_REFRESH_TOKEN");

RefreshTokenParameters parameters = RefreshTokenParameters.builder(scopes, rt).build();

PublicClientApplication app = PublicClientApplication.builder(CLIENT_ID) // ClientId for your application
                .authority(AUTHORITY)  //plug in your authority
                .build();

IAuthenticationResult result = app.acquireToken(parameters);

The IAuthenticationResult returns an access token and ID token, while your new refresh token is stored in the cache. The application will also now contain an IAccount:

Set<IAccount> accounts =  app.getAccounts().join();

To use the tokens that are now in the cache, call:

SilentParameters parameters = SilentParameters.builder(scope, accounts.iterator().next()).build();
IAuthenticationResult result = app.acquireToken(parameters);

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