Top 5 authentication solutions for secure Java apps in 2026

Authentication is a critical component of any Java application, and developers benefit from both the ecosystem's mature authentication frameworks and modern cloud-based solutions. Whether you're building a B2B SaaS platform with Spring Boot, a Kotlin-based microservices architecture, or a traditional Java web application, choosing the right authentication approach can significantly impact your development velocity and feature capabilities.

Java's enterprise heritage means authentication and security have always been first-class concerns in the ecosystem. Spring Security provides powerful authentication primitives, while Java EE (Jakarta EE) offers standard specifications. However, enterprise features like SAML SSO and SCIM provisioning typically require specialized solutions beyond what frameworks provide out of the box.

In this guide, we'll explore the top 5 authentication solutions for Java apps in 2026, from enterprise platforms to Java-native authentication frameworks.

What to look for in an auth provider for Java apps

Before diving into specific solutions, let's identify the key features that make an authentication provider ideal for Java:

• ‍Java SDK support: The best auth solutions provide native Java SDKs with idiomatic Java code, proper exception handling, and Maven/Gradle integration. Look for providers with well-maintained Java libraries that follow Java conventions.‍
• Spring Boot integration: Most modern Java applications use Spring Boot. Your auth solution should integrate naturally with Spring Security, Spring MVC, and Spring's dependency injection.‍
• Jakarta EE compatibility: For enterprise applications using Jakarta EE (formerly Java EE), your auth solution should work with standard specifications like JAAS, servlet filters, and CDI.‍
• Enterprise features: For B2B applications, you'll need SSO support (SAML, OIDC), directory sync (SCIM), multi-tenancy, and organization management. These features should be first-class, especially given Java's strong enterprise adoption.‍
• Microservices ready: Many Java applications are built as microservices. Your auth solution should support distributed authentication patterns, JWT validation, and service-to-service authentication.‍
• Database integration: If your auth solution stores users in a database, it should work naturally with JPA/Hibernate and follow Java data access patterns.‍
• Security best practices: Your provider should handle security concerns like password hashing with bcrypt/PBKDF2, secure token handling, CSRF protection, and session management following OWASP guidelines.‍
• Performance: Java applications often handle high throughput. Your auth solution needs efficient token validation and minimal latency for authorization checks.
• Kotlin support: For teams using Kotlin, look for native Kotlin SDKs with coroutines support for non-blocking operations and idiomatic Kotlin patterns rather than just Java-compatible libraries.

Now let's look at the top 5 solutions and whether they meet these criteria.

1. WorkOS

WorkOS is an enterprise authentication platform built specifically for B2B SaaS applications. It provides a comprehensive suite of authentication and user management features designed to help you sell to enterprise customers faster, with excellent Java and Kotlin SDK support that integrates seamlessly with Spring Boot and other Java frameworks.

Key features

• Kotlin SDK: Native Kotlin SDK with coroutines support and idiomatic Kotlin patterns.
• AI-powered CLI: Instantly integrate AuthKit with npx workos@latest. The CLI automatically detects your .NET project and updates your code with authentication.
• ‍Sessions model with access + refresh tokens and guidance for secure cookie storage.
• Flexible UI support via APIs and SDKs, with AuthKit as a highly customizable hosted login powered by Radix.
• Enterprise SSO with native SAML and OIDC, configurable by customers through an Admin Portal.‍
• SCIM provisioning: Automated user provisioning and deprovisioning that enterprises expect, handling the "remove this employee immediately" requests that inevitably arrive. Real-time synchronization with any identity provider (Okta, Azure AD, Google Workspace, and more).
• Tamper-proof audit logs for SOC 2, HIPAA, and GDPR.‍
• Passkeys, MFA, social logins, magic auth, and more.
• Secure session handling with server-side validation and instant session revocation capabilities.‍
• Customizable JWT claims: Add custom data to JWT payloads with JWT templates for flexible token customization.‍
• Radar for suspicious login detection and threat monitoring that alerts you to potential account compromises.
• Fine-grained authorization: Role-based access control with customizable permissions.‍
• Feature flags: Integrated feature flagging for gradual rollouts.
• First-class multi-tenancy with organization management, member invitations, and role assignment.‍
• Enterprise SLA and dedicated support.‍
• Pricing that scales with growth, with $0 for the first 1 million users.

Best for

WorkOS is ideal for B2B SaaS companies building on Java or Kotlin that need to sell to enterprise customers. If your roadmap includes features like SSO, SCIM provisioning, or advanced multi-tenancy, WorkOS provides these out of the box instead of requiring months of custom development.

Trade-offs

If you truly only need a quick OAuth login for a hobby app, WorkOS can feel like bringing a well-organized toolbox to hang a single picture. The upside is: you won’t have to rebuild your walls later.

2. Spring Security

Spring Security is the de facto standard for securing Spring-based applications, providing comprehensive authentication and authorization support. It's deeply integrated with the Spring ecosystem and offers extensive customization options.

Key features

• Spring native: Deep integration with Spring Boot, Spring MVC, and the entire Spring ecosystem.
• Multiple authentication mechanisms: Form login, HTTP Basic, OAuth2, SAML, LDAP support.
• Method security: Protect methods using annotations like @PreAuthorize and @Secured.
• Session management: Built-in session fixation protection, concurrent session control.
• CSRF protection: Automatic CSRF token generation and validation.
• Security filters: Extensive filter chain for request processing and authentication.

Best for

Spring Security works for Java applications built with Spring Boot or Spring Framework that need full control over authentication implementation. It's suitable for teams with strong Spring expertise who want to own their authentication logic and customize every aspect of security, though you'll need to implement enterprise features yourself.

Trade-offs

• Configuration complexity for advanced use cases. Spring Security's power comes with a steep learning curve.
• No enterprise SSO out of the box. While Spring Security supports OAuth2 and SAML, integrating with specific enterprise IdPs requires significant custom configuration.
• No SCIM provisioning or directory sync. Enterprise user lifecycle management requires custom development.
• Multi-tenancy requires custom architecture. No built-in multi-tenant patterns for B2B SaaS.
• No pre-built UI components. You'll need to build login pages, password reset flows, and account management interfaces.
• No built-in audit logging for compliance. Tracking authentication events requires custom implementation.
• Session management across microservices is complex. Distributed session handling requires additional infrastructure like Redis.
• Social login requires manual OAuth2 client configuration for each provider.
• Magic links and passwordless authentication require custom implementation.
• No admin dashboard or user management interface. All user administration must be custom-built.

3. Apache Shiro

Apache Shiro is a lightweight, powerful Java security framework that provides authentication, authorization, cryptography, and session management. It's designed to be simple to use while providing comprehensive security features for Java applications.

Key features

• Simple API: Easy-to-understand API with straightforward authentication and authorization patterns.
• Framework agnostic: Works with Spring, Grails, Guice, web frameworks, and standalone Java applications.
• Session management: Built-in session management that works in any environment, not just web applications.
• Cryptography: Built-in cryptographic ciphers for password hashing and data encryption.
• Realm support: Pluggable data sources (JDBC, LDAP, Active Directory, custom) for user authentication.
• Caching: Built-in caching support for improved performance.

Best for

Apache Shiro works for Java applications that need a lightweight, straightforward security framework without the complexity of Spring Security. It's suitable for teams building applications outside the Spring ecosystem or those wanting simpler security patterns, though you'll need to handle enterprise features and infrastructure yourself.

Trade-offs

• No enterprise SSO support. SAML and advanced OIDC integration require custom development or third-party extensions.
• No SCIM provisioning or directory sync capabilities for enterprise user lifecycle management.
• Multi-tenancy requires custom architecture and implementation.
• Smaller community compared to Spring Security. Fewer resources, examples, and third-party integrations available.
• No pre-built UI components. You'll need to build authentication interfaces yourself.
• No built-in audit logging for compliance. Tracking security events requires custom implementation.
• Session management in distributed systems requires careful configuration. Clustering and session replication need manual setup.
• Limited OAuth2 support. Modern OAuth flows require additional libraries or custom implementation.
• No magic links or passwordless authentication built-in.
• Documentation can be sparse for advanced use cases compared to more popular frameworks.

4. Pac4j

Pac4j is a comprehensive Java security framework that provides authentication and authorization across multiple protocols and frameworks. It's designed to work with various Java frameworks (Spring, Play, Vertx, etc.) and supports multiple authentication protocols in a unified way.

Key features

• Multi-protocol support: OAuth, SAML, CAS, OpenID Connect, LDAP, JWT, and more in one framework.
• Framework agnostic: Works with Spring Boot, Play Framework, Spark Java, Vertx, Javalin, and others.
• Unified API: Single consistent API for all authentication mechanisms and protocols.
• Social authentication: Pre-built support for 50+ OAuth providers (Google, Facebook, GitHub, etc.).
• Authorization support: Profile-based and role-based authorization patterns.
• Client and server: Can act as both authentication client and authorization server.

Best for

Pac4j works for Java applications that need to support multiple authentication protocols (OAuth, SAML, OIDC) with a unified API, or applications using frameworks outside the Spring ecosystem. It's suitable for teams that need protocol flexibility and don't want to be locked into a single framework, though you'll need to handle infrastructure, enterprise directory sync, and UI components yourself.

Trade-offs

• Configuration can be complex. Supporting multiple protocols means understanding each protocol's nuances and configuration.
• No SCIM provisioning or directory sync. Enterprise user lifecycle management requires custom development.
• Multi-tenancy requires custom architecture on top of Pac4j's authentication mechanisms.
• No pre-built UI components. You'll need to build login pages and authentication flows yourself.
• Limited Spring Boot integration compared to Spring Security. Requires manual configuration and setup.
• No built-in audit logging for compliance. Tracking authentication events requires custom implementation.
• Documentation quality varies. Some protocols and integrations have better documentation than others.
• Session management in distributed systems requires external solutions. No built-in distributed session handling.
• No admin dashboard or user management interface. All user administration must be custom-built.
• Smaller community than Spring Security. Fewer examples and third-party resources available.

5. Keycloak

Keycloak is an open-source identity and access management (IAM) platform that provides comprehensive authentication and authorization capabilities. Built in Java and designed for enterprise use, it's a natural fit for Java applications requiring self-hosted identity infrastructure.

Key features

• Open-source IAM: Complete identity and access management platform with no licensing fees.
• Single sign-on (SSO): Support for SAML, OpenID Connect, and OAuth 2.0 protocols.
• Identity brokering: Authenticate users via external identity providers like Google, Facebook, or enterprise IdPs.
• User federation: Connect to existing user databases via LDAP or Active Directory.
• Admin console: Web-based admin interface for managing realms, clients, users, and roles.
• Java native: Built in Java with excellent integration for Java applications.

Best for

Keycloak works for Java organizations that need enterprise IAM features, want to self-host their authentication infrastructure, and have operational expertise to deploy and maintain the platform. It's particularly well-suited for Java shops given its Java foundation and natural integration with Java applications, though you'll need to manage infrastructure and handle configuration complexity yourself.

Trade-offs

• Self-hosted infrastructure. You're responsible for deploying, scaling, monitoring, and maintaining Keycloak servers and databases.
• Configuration complexity. While powerful, Keycloak's extensive configuration options can be overwhelming and require time to learn.
• Spring Boot integration requires custom work. While Keycloak provides Java adapters, deep Spring Security integration requires configuration.
• Resource-intensive. Keycloak can be heavy on resources, especially for high-traffic applications.
• UI customization is limited. While you can theme login pages, creating custom authentication flows requires deeper modifications.
• Updates and maintenance burden. Security patches, version upgrades, and database migrations are your responsibility.
• No built-in multi-tenancy for B2B SaaS. You'll need to design realm-per-tenant or shared-realm architectures yourself.
• No SCIM provisioning built-in. Enterprise directory sync requires additional development.
• Operational expertise required. Running Keycloak at scale with high availability requires infrastructure knowledge.

Choosing the right solution for your Java apps

The best authentication solution depends on your specific needs:

Choose WorkOS if you're building a B2B SaaS application that needs to sell to enterprise customers. The enterprise SSO, SCIM, multi-tenancy, admin portal, fine-grained authorization, and managed service mean you can focus on building your application instead of authentication infrastructure. WorkOS is the only solution that combines enterprise features, Java/Kotlin SDKs, and managed service without requiring deep authentication expertise.

Choose Spring Security if you're building a Spring-based application and want full control over authentication implementation with deep framework integration. It's perfect for teams with strong Spring expertise, though you'll need to implement enterprise features, UI components, multi-tenancy, and audit logging yourself.

Choose Apache Shiro if you want a lightweight, straightforward security framework without Spring Security's complexity or if you're building outside the Spring ecosystem. It provides simpler security patterns with good performance, though you'll need to handle enterprise features, protocol integrations, and infrastructure yourself.

Choose Pac4j if you need to support multiple authentication protocols (OAuth, SAML, OIDC) with a unified API, or you're using Java frameworks outside the Spring ecosystem. It provides protocol flexibility and framework agnosticism, though configuration can be complex and you'll need to build enterprise features and UI components yourself.

Choose Keycloak if you need enterprise IAM features, want to self-host your authentication infrastructure, and have operational expertise with Java applications. Being Java-native makes it a natural fit for Java shops, though you'll need to manage infrastructure, handle configuration complexity, and implement features like SCIM yourself.

Conclusion

Authentication in Java can be as straightforward or sophisticated as your requirements demand. The ecosystem's mature frameworks and enterprise focus provide excellent options for any authentication scenario, from traditional web applications to modern microservices architectures.

Java-native frameworks like Spring Security, Apache Shiro, and Pac4j provide deep integration and control but require significant development effort for enterprise features. Self-hosted solutions like Keycloak offer comprehensive IAM capabilities but come with operational overhead.

For B2B SaaS companies building on Java or Kotlin that need to sell to enterprise customers, WorkOS provides the most complete solution. The Java and Kotlin SDKs integrate seamlessly with Spring Boot and other Java frameworks. Enterprise SSO, SCIM provisioning, directory sync, and multi-tenancy work out of the box, not as features requiring months of custom development. Fine-grained authorization, audit logging, and feature flags are built into the platform. And the managed service means you can focus on building your application instead of maintaining authentication infrastructure.

If you're building for enterprise customers and need a solution that combines Java-native integration, enterprise features, and managed service reliability, WorkOS provides the comprehensive authentication platform Java applications need in 2026.