Client Management

/**
 * AWS Lambda synchronous client interface
 * Provides access to all Lambda service operations with blocking execution
 */
public interface AWSLambda {
    /** Service endpoint prefix */
    String ENDPOINT_PREFIX = "lambda";
    
    // Function Management
    CreateFunctionResult createFunction(CreateFunctionRequest request);
    GetFunctionResult getFunction(GetFunctionRequest request);
    UpdateFunctionCodeResult updateFunctionCode(UpdateFunctionCodeRequest request);
    UpdateFunctionConfigurationResult updateFunctionConfiguration(UpdateFunctionConfigurationRequest request);
    DeleteFunctionResult deleteFunction(DeleteFunctionRequest request);
    ListFunctionsResult listFunctions(ListFunctionsRequest request);
    ListFunctionsResult listFunctions(); // Simplified overload
    GetFunctionConfigurationResult getFunctionConfiguration(GetFunctionConfigurationRequest request);
    
    // Function Invocation
    InvokeResult invoke(InvokeRequest request);
    InvokeAsyncResult invokeAsync(InvokeAsyncRequest request); // Deprecated
    
    // Version and Alias Management
    PublishVersionResult publishVersion(PublishVersionRequest request);
    ListVersionsByFunctionResult listVersionsByFunction(ListVersionsByFunctionRequest request);
    CreateAliasResult createAlias(CreateAliasRequest request);
    GetAliasResult getAlias(GetAliasRequest request);
    UpdateAliasResult updateAlias(UpdateAliasRequest request);
    DeleteAliasResult deleteAlias(DeleteAliasRequest request);
    ListAliasesResult listAliases(ListAliasesRequest request);
    
    // Event Source Mapping
    CreateEventSourceMappingResult createEventSourceMapping(CreateEventSourceMappingRequest request);
    GetEventSourceMappingResult getEventSourceMapping(GetEventSourceMappingRequest request);
    UpdateEventSourceMappingResult updateEventSourceMapping(UpdateEventSourceMappingRequest request);
    DeleteEventSourceMappingResult deleteEventSourceMapping(DeleteEventSourceMappingRequest request);
    ListEventSourceMappingsResult listEventSourceMappings(ListEventSourceMappingsRequest request);
    ListEventSourceMappingsResult listEventSourceMappings(); // Simplified overload
    
    // Layer Management
    PublishLayerVersionResult publishLayerVersion(PublishLayerVersionRequest request);
    GetLayerVersionResult getLayerVersion(GetLayerVersionRequest request);
    GetLayerVersionByArnResult getLayerVersionByArn(GetLayerVersionByArnRequest request);
    DeleteLayerVersionResult deleteLayerVersion(DeleteLayerVersionRequest request);
    ListLayersResult listLayers(ListLayersRequest request);
    ListLayerVersionsResult listLayerVersions(ListLayerVersionsRequest request);
    AddLayerVersionPermissionResult addLayerVersionPermission(AddLayerVersionPermissionRequest request);
    RemoveLayerVersionPermissionResult removeLayerVersionPermission(RemoveLayerVersionPermissionRequest request);
    GetLayerVersionPolicyResult getLayerVersionPolicy(GetLayerVersionPolicyRequest request);
    
    // Concurrency Management
    PutFunctionConcurrencyResult putFunctionConcurrency(PutFunctionConcurrencyRequest request);
    GetFunctionConcurrencyResult getFunctionConcurrency(GetFunctionConcurrencyRequest request);
    DeleteFunctionConcurrencyResult deleteFunctionConcurrency(DeleteFunctionConcurrencyRequest request);
    PutProvisionedConcurrencyConfigResult putProvisionedConcurrencyConfig(PutProvisionedConcurrencyConfigRequest request);
    GetProvisionedConcurrencyConfigResult getProvisionedConcurrencyConfig(GetProvisionedConcurrencyConfigRequest request);
    DeleteProvisionedConcurrencyConfigResult deleteProvisionedConcurrencyConfig(DeleteProvisionedConcurrencyConfigRequest request);
    ListProvisionedConcurrencyConfigsResult listProvisionedConcurrencyConfigs(ListProvisionedConcurrencyConfigsRequest request);
    
    // Code Signing
    CreateCodeSigningConfigResult createCodeSigningConfig(CreateCodeSigningConfigRequest request);
    GetCodeSigningConfigResult getCodeSigningConfig(GetCodeSigningConfigRequest request);
    UpdateCodeSigningConfigResult updateCodeSigningConfig(UpdateCodeSigningConfigRequest request);
    DeleteCodeSigningConfigResult deleteCodeSigningConfig(DeleteCodeSigningConfigRequest request);
    ListCodeSigningConfigsResult listCodeSigningConfigs(ListCodeSigningConfigsRequest request);
    PutFunctionCodeSigningConfigResult putFunctionCodeSigningConfig(PutFunctionCodeSigningConfigRequest request);
    GetFunctionCodeSigningConfigResult getFunctionCodeSigningConfig(GetFunctionCodeSigningConfigRequest request);
    DeleteFunctionCodeSigningConfigResult deleteFunctionCodeSigningConfig(DeleteFunctionCodeSigningConfigRequest request);
    ListFunctionsByCodeSigningConfigResult listFunctionsByCodeSigningConfig(ListFunctionsByCodeSigningConfigRequest request);
    
    // Function URLs
    CreateFunctionUrlConfigResult createFunctionUrlConfig(CreateFunctionUrlConfigRequest request);
    GetFunctionUrlConfigResult getFunctionUrlConfig(GetFunctionUrlConfigRequest request);
    UpdateFunctionUrlConfigResult updateFunctionUrlConfig(UpdateFunctionUrlConfigRequest request);
    DeleteFunctionUrlConfigResult deleteFunctionUrlConfig(DeleteFunctionUrlConfigRequest request);
    ListFunctionUrlConfigsResult listFunctionUrlConfigs(ListFunctionUrlConfigsRequest request);
    
    // Event Invoke Configuration
    PutFunctionEventInvokeConfigResult putFunctionEventInvokeConfig(PutFunctionEventInvokeConfigRequest request);
    GetFunctionEventInvokeConfigResult getFunctionEventInvokeConfig(GetFunctionEventInvokeConfigRequest request);
    UpdateFunctionEventInvokeConfigResult updateFunctionEventInvokeConfig(UpdateFunctionEventInvokeConfigRequest request);
    DeleteFunctionEventInvokeConfigResult deleteFunctionEventInvokeConfig(DeleteFunctionEventInvokeConfigRequest request);
    ListFunctionEventInvokeConfigsResult listFunctionEventInvokeConfigs(ListFunctionEventInvokeConfigsRequest request);
    
    // Permissions and Policies
    AddPermissionResult addPermission(AddPermissionRequest request);
    RemovePermissionResult removePermission(RemovePermissionRequest request);
    GetPolicyResult getPolicy(GetPolicyRequest request);
    
    // Tagging
    TagResourceResult tagResource(TagResourceRequest request);
    UntagResourceResult untagResource(UntagResourceRequest request);
    ListTagsResult listTags(ListTagsRequest request);
    
    // Account and Runtime Management
    GetAccountSettingsResult getAccountSettings(GetAccountSettingsRequest request);
    GetRuntimeManagementConfigResult getRuntimeManagementConfig(GetRuntimeManagementConfigRequest request);
    PutRuntimeManagementConfigResult putRuntimeManagementConfig(PutRuntimeManagementConfigRequest request);
    
    // Utility Methods
    void shutdown();
    ResponseMetadata getCachedResponseMetadata(AmazonWebServiceRequest request);
    AWSLambdaWaiters waiters();
}

/**
 * AWS Lambda asynchronous client interface
 * All operations return Future objects and support AsyncHandler callbacks
 */
public interface AWSLambdaAsync extends AWSLambda {
    // All methods from AWSLambda plus async versions:
    
    /**
     * Asynchronous function creation with callback support
     * @param request Function creation parameters
     * @param asyncHandler Optional callback handler for completion notification
     * @return Future containing CreateFunctionResult
     */
    Future<CreateFunctionResult> createFunctionAsync(
        CreateFunctionRequest request,
        AsyncHandler<CreateFunctionRequest, CreateFunctionResult> asyncHandler
    );
    
    /**
     * Asynchronous function invocation
     * @param request Invocation parameters
     * @param asyncHandler Optional callback handler
     * @return Future containing InvokeResult
     */
    Future<InvokeResult> invokeAsync(
        InvokeRequest request,
        AsyncHandler<InvokeRequest, InvokeResult> asyncHandler
    );
    
    // Similar async methods for all other operations...
}

/**
 * Builder for creating AWSLambda client instances with custom configuration
 */
public final class AWSLambdaClientBuilder 
    extends AwsSyncClientBuilder<AWSLambdaClientBuilder, AWSLambda> {
    
    /**
     * Create default builder instance
     * @return New AWSLambdaClientBuilder
     */
    public static AWSLambdaClientBuilder standard();
    
    /**
     * Create default client with standard configuration
     * @return Configured AWSLambda client
     */
    public static AWSLambda defaultClient();
    
    /**
     * Build the configured client
     * @return AWSLambda client instance
     */
    @Override
    public AWSLambda build();
}

/**
 * Builder for creating AWSLambdaAsync client instances
 */
public final class AWSLambdaAsyncClientBuilder 
    extends AwsAsyncClientBuilder<AWSLambdaAsyncClientBuilder, AWSLambdaAsync> {
    
    /**
     * Create default async builder
     * @return New AWSLambdaAsyncClientBuilder
     */
    public static AWSLambdaAsyncClientBuilder standard();
    
    /**
     * Create default async client
     * @return Configured AWSLambdaAsync client
     */
    public static AWSLambdaAsync defaultClient();
    
    /**
     * Build the configured async client
     * @return AWSLambdaAsync client instance
     */
    @Override
    public AWSLambdaAsync build();
}

/**
 * Abstract base class for custom AWSLambda implementations
 * Provides default implementations for utility methods
 */
public abstract class AbstractAWSLambda implements AWSLambda {
    protected AbstractAWSLambda();
    
    @Override
    public void shutdown() {
        // Default implementation
    }
    
    @Override
    public ResponseMetadata getCachedResponseMetadata(AmazonWebServiceRequest request) {
        // Default implementation
        return null;
    }
    
    @Override
    public AWSLambdaWaiters waiters() {
        // Default waiter implementation
        return new AWSLambdaWaiters(this);
    }
}

/**
 * Abstract base class for custom AWSLambdaAsync implementations
 */
public abstract class AbstractAWSLambdaAsync extends AbstractAWSLambda implements AWSLambdaAsync {
    protected AbstractAWSLambdaAsync();
    
    // Provides default async implementations that delegate to sync methods
    @Override
    public Future<CreateFunctionResult> createFunctionAsync(
        CreateFunctionRequest request,
        AsyncHandler<CreateFunctionRequest, CreateFunctionResult> asyncHandler
    ) {
        // Default async delegation implementation
        return null;
    }
    
    // Similar default implementations for other async methods...
}

import com.amazonaws.services.lambda.*;
import com.amazonaws.auth.profile.ProfileCredentialsProvider;
import com.amazonaws.regions.Regions;

// Standard synchronous client
AWSLambda lambdaClient = AWSLambdaClientBuilder.standard()
    .withRegion(Regions.US_EAST_1)
    .build();

// Configured synchronous client
AWSLambda configuredClient = AWSLambdaClientBuilder.standard()
    .withRegion(Regions.US_WEST_2)
    .withCredentials(new ProfileCredentialsProvider("myprofile"))
    .build();

// Asynchronous client
AWSLambdaAsync asyncClient = AWSLambdaAsyncClientBuilder.standard()
    .withRegion(Regions.EU_WEST_1)
    .build();

// Default clients (uses default credential chain and region)
AWSLambda defaultClient = AWSLambdaClientBuilder.defaultClient();
AWSLambdaAsync defaultAsync = AWSLambdaAsyncClientBuilder.defaultClient();

// Don't forget to shutdown when done
lambdaClient.shutdown();
asyncClient.shutdown();