Configuration Overrides

/**
 * Abstract base class for runtime configuration overrides
 */
public abstract class ConfigOverride {
    
    // Static factory methods for simple key-value overrides
    /**
     * Create a simple configuration override with default prefix
     * @param key Configuration property key (will be prefixed with "dw.")
     * @param value Configuration property value
     * @return ConfigOverride instance for the key-value pair
     */
    public static ConfigOverride config(String key, String value);
    
    /**
     * Create a configuration override with custom prefix
     * @param propertyPrefix Custom prefix for the configuration property
     * @param key Configuration property key
     * @param value Configuration property value
     * @return ConfigOverride instance for the prefixed key-value pair
     */
    public static ConfigOverride config(String propertyPrefix, String key, String value);
    
    // Static factory methods for lazy-evaluated overrides
    /**
     * Create a configuration override with lazy-evaluated value
     * @param key Configuration property key (will be prefixed with "dw.")
     * @param value Supplier providing the configuration value when needed
     * @return ConfigOverride instance with lazy evaluation
     */
    public static ConfigOverride config(String key, Supplier<String> value);
    
    /**
     * Create a configuration override with custom prefix and lazy evaluation
     * @param propertyPrefix Custom prefix for the configuration property
     * @param key Configuration property key
     * @param value Supplier providing the configuration value when needed
     * @return ConfigOverride instance with custom prefix and lazy evaluation
     */
    public static ConfigOverride config(String propertyPrefix, String key, Supplier<String> value);
    
    // Static factory methods for random port assignment
    /**
     * Create random port assignments for server.applicationConnectors[0].port and 
     * server.adminConnectors[0].port using default prefix
     * @return ConfigOverride instance for random port assignment
     */
    public static ConfigOverride randomPorts();
    
    /**
     * Create random port assignments with custom property prefix
     * @param propertyPrefix Custom prefix for port configuration properties
     * @return ConfigOverride instance for random port assignment with custom prefix
     */
    public static ConfigOverride randomPorts(String propertyPrefix);
    
    // Abstract lifecycle methods
    /**
     * Apply the configuration override to system properties
     * Called before application startup
     */
    public abstract void addToSystemProperties();
    
    /**
     * Remove the configuration override from system properties
     * Called after application shutdown for cleanup
     */
    public abstract void removeFromSystemProperties();
    
    // Constants
    /**
     * Default property prefix used by Dropwizard configuration system
     */
    public static final String DEFAULT_PREFIX = "dw.";
}

// Simple property override
ConfigOverride dbOverride = ConfigOverride.config("database.url", "jdbc:h2:mem:test");

// Custom prefix override
ConfigOverride customOverride = ConfigOverride.config("myapp.", "feature.enabled", "true");

// Lazy evaluation for dynamic values
ConfigOverride dynamicOverride = ConfigOverride.config("timestamp", 
    () -> String.valueOf(System.currentTimeMillis()));

// Random port assignment (most common use case)
ConfigOverride randomPorts = ConfigOverride.randomPorts();

// Random ports with custom prefix
ConfigOverride customRandomPorts = ConfigOverride.randomPorts("myapp.");

// Use with DropwizardTestSupport
DropwizardTestSupport<MyConfiguration> testSupport = 
    new DropwizardTestSupport<>(
        MyApplication.class,
        "test-config.yml",
        ConfigOverride.randomPorts(),
        ConfigOverride.config("database.url", "jdbc:h2:mem:test"),
        ConfigOverride.config("redis.enabled", "false")
    );

// Multiple overrides for complex test scenarios
ConfigOverride[] overrides = {
    ConfigOverride.randomPorts(),
    ConfigOverride.config("database.url", "jdbc:h2:mem:test"),
    ConfigOverride.config("database.user", "sa"),
    ConfigOverride.config("database.password", ""),
    ConfigOverride.config("logging.level", "DEBUG"),
    ConfigOverride.config("metrics.enabled", "false")
};

DropwizardTestSupport<MyConfiguration> testSupport = 
    new DropwizardTestSupport<>(MyApplication.class, "test-config.yml", overrides);

/**
 * Concrete implementation for key-value configuration overrides
 * Created by ConfigOverride.config() factory methods
 */
class ConfigOverrideValue extends ConfigOverride {
    // Package-private implementation class
    // Use ConfigOverride.config() factory methods to create instances
}

/**
 * Concrete implementation for random port assignment
 * Created by ConfigOverride.randomPorts() factory methods
 */
class ConfigOverrideRandomPorts extends ConfigOverride {
    // Package-private implementation class
    // Use ConfigOverride.randomPorts() factory methods to create instances
}

// H2 in-memory database for testing
ConfigOverride.config("database.url", "jdbc:h2:mem:test"),
ConfigOverride.config("database.user", "sa"),
ConfigOverride.config("database.password", ""),
ConfigOverride.config("database.driverClass", "org.h2.Driver")

// PostgreSQL test database
ConfigOverride.config("database.url", "jdbc:postgresql://localhost:5432/test_db"),
ConfigOverride.config("database.user", "test_user"),
ConfigOverride.config("database.password", "test_password")

// Enable debug logging for tests
ConfigOverride.config("logging.level", "DEBUG"),
ConfigOverride.config("logging.loggers.com.mycompany", "TRACE")

// Disable logging for performance tests
ConfigOverride.config("logging.level", "OFF")

// Disable external service integrations
ConfigOverride.config("externalServices.enabled", "false"),
ConfigOverride.config("caching.enabled", "false"),
ConfigOverride.config("metrics.enabled", "false")

// Enable test-specific features
ConfigOverride.config("testMode.enabled", "true"),
ConfigOverride.config("testData.autoLoad", "true")

// Random ports (most common)
ConfigOverride.randomPorts()

// Specific ports for integration tests
ConfigOverride.config("server.applicationConnectors[0].port", "8080"),
ConfigOverride.config("server.adminConnectors[0].port", "8081")

// Custom connector configurations
ConfigOverride.config("server.applicationConnectors[0].type", "http"),
ConfigOverride.config("server.applicationConnectors[0].bindHost", "localhost")

// Disable authentication for testing
ConfigOverride.config("auth.enabled", "false"),
ConfigOverride.config("csrf.enabled", "false")

// Test-specific authentication
ConfigOverride.config("auth.testMode", "true"),
ConfigOverride.config("auth.testUser", "test@example.com")