Togglz: Feature Toggle Framework for Java

Togglz is a feature toggle (feature flag) framework for Java applications that enables you to control feature availability at runtime without redeploying code.

Key Features

Core Concepts

1. Feature Enum

Define your features as an enum:

public enum MyFeatures implements Feature {
    @Label("New Dashboard")
    NEW_DASHBOARD,

    @Label("Beta Checkout")
    BETA_CHECKOUT,

    @Label("Advanced Analytics")
    ADVANCED_ANALYTICS;

    public String name() {
        return toString().toLowerCase();
    }
}

2. Feature State Provider

Determines if a feature is active:

@Configuration
public class TogglzConfiguration {

    @Bean
    public FeatureProvider featureProvider() {
        return new InMemoryStateRepository();
    }

    @Bean
    public UserProvider userProvider() {
        return new UserProvider() {
            @Override
            public FeatureUser getCurrentUser() {
                Authentication auth = SecurityContextHolder.getContext().getAuthentication();
                return new FeatureUser(auth.getName(), auth.getAuthorities()
                    .stream()
                    .map(GrantedAuthority::getAuthority)
                    .collect(Collectors.toList()));
            }
        };
    }
}

3. Using Feature Toggles

@Service
public class OrderService {

    @Autowired
    private FeatureManager featureManager;

    public void processOrder(Order order) {
        if (featureManager.isActive(MyFeatures.BETA_CHECKOUT)) {
            // New checkout logic
            processBetaCheckout(order);
        } else {
            // Legacy checkout logic
            processLegacyCheckout(order);
        }
    }
}

4. Annotation-Based Approach

@Service
public class DashboardService {

    @FeatureActive(MyFeatures.NEW_DASHBOARD)
    public Dashboard getNewDashboard() {
        return new ModernDashboard();
    }

    public Dashboard getDashboard() {
        if (featureManager.isActive(MyFeatures.NEW_DASHBOARD)) {
            return getNewDashboard();
        }
        return getLegacyDashboard();
    }
}

Configuration Example

@Configuration
@EnableTogglz
public class TogglzConfig {

    @Bean
    public TogglzConfig togglzConfig() {
        return TogglzConfig.builder()
            .featureProvider(new InMemoryStateRepository())
            .userProvider(new UserProvider() {
                @Override
                public FeatureUser getCurrentUser() {
                    // Return current user
                    return null;
                }
            })
            .stateRepository(new InMemoryStateRepository())
            .console()
                .path("/togglz-console")
                .enabled(true)
                .build();
    }
}

State Repositories

// File-based
new FileBasedStateRepository(new File("togglz.properties"))

// Database
new JDBCStateRepository(dataSource)

// In-memory
new InMemoryStateRepository()

// Redis
new RedisStateRepository(redisClient)

Admin Console

Access the web console at /togglz-console to:

• View all features
• Enable/disable features
• Set user-specific activations
• View activation strategies

Activation Strategies

featureManager.isActive(MyFeatures.NEW_DASHBOARD, 
    new ActivationStrategy() {
        @Override
        public boolean isActive(Feature feature, ActivationContext context) {
            // Custom logic
            return context.getUser().getName().startsWith("admin");
        }
    });

Benefits

✅ Zero Downtime Deployments - Deploy code with features disabled
✅ Gradual Rollouts - Enable for percentage of users
✅ Quick Rollback - Disable problematic features instantly
✅ A/B Testing - Compare feature variants
✅ Operational Control - Non-technical users can manage toggles

Maven Dependency

<dependency>
    <groupId>org.togglz</groupId>
    <artifactId>togglz-spring-boot-starter</artifactId>
    <version>3.4.0</version>
</dependency>

Togglz is essential for modern continuous deployment practices, enabling teams to decouple feature releases from code deployments.