CLI Interface

/**
 * Main entry point for Flink command line interface
 */
public class CliFrontend {
    /**
     * Creates CLI frontend with configuration and custom command lines
     * @param configuration Flink configuration
     * @param customCommandLines List of custom command line implementations
     */
    public CliFrontend(Configuration configuration, List<CustomCommandLine> customCommandLines);

    /**
     * Main method for CLI execution
     * @param args Command line arguments
     */
    public static void main(String[] args);

    /**
     * Runs CLI with given arguments
     * @param args Command line arguments
     * @return Exit code (0 for success, non-zero for error)
     */
    public int run(String[] args);

    /**
     * Lists jobs on the cluster
     * @param args Command line arguments for list operation
     * @return Exit code
     */
    public int list(String[] args);

    /**
     * Cancels a running job
     * @param args Command line arguments for cancel operation
     * @return Exit code
     */
    public int cancel(String[] args);

    /**
     * Stops a running job
     * @param args Command line arguments for stop operation
     * @return Exit code
     */
    public int stop(String[] args);

    /**
     * Manages savepoints (create, dispose, etc.)
     * @param args Command line arguments for savepoint operation
     * @return Exit code
     */
    public int savepoint(String[] args);
}

import org.apache.flink.client.cli.CliFrontend;
import org.apache.flink.configuration.Configuration;

// Create CLI frontend
Configuration config = new Configuration();
List<CustomCommandLine> customCLIs = Arrays.asList(new DefaultCLI(), new GenericCLI());
CliFrontend cli = new CliFrontend(config, customCLIs);

// Execute CLI commands programmatically
int exitCode;

// List jobs
exitCode = cli.list(new String[]{"list"});

// Cancel a job
exitCode = cli.cancel(new String[]{"cancel", "a1b2c3d4e5f6"});

// Create savepoint
exitCode = cli.savepoint(new String[]{"savepoint", "a1b2c3d4e5f6", "/path/to/savepoint"});

/**
 * Interface for custom command line implementations
 */
public interface CustomCommandLine {
    /**
     * Checks if this command line is active for given arguments
     * @param commandLine Parsed command line
     * @return true if this CLI should handle the command
     */
    boolean isActive(CommandLine commandLine);

    /**
     * Gets the unique identifier for this command line
     * @return Unique string identifier
     */
    String getId();

    /**
     * Adds run options to the options parser
     * @param options Options instance to add to
     */
    void addRunOptions(Options options);

    /**
     * Adds general options to the options parser
     * @param options Options instance to add to
     */
    void addGeneralOptions(Options options);

    /**
     * Applies command line options to configuration
     * @param commandLine Parsed command line
     * @return Updated configuration with CLI options applied
     */
    Configuration applyCommandLineOptionsToConfiguration(CommandLine commandLine);
}

/**
 * Base class for custom command line interfaces
 */
public abstract class AbstractCustomCommandLine implements CustomCommandLine {
    @Override
    public boolean isActive(CommandLine commandLine);

    @Override
    public String getId();

    @Override
    public void addRunOptions(Options options);

    @Override
    public void addGeneralOptions(Options options);
}

/**
 * Default command line interface implementation
 */
public class DefaultCLI extends AbstractCustomCommandLine {
    // Default implementation for standard Flink CLI operations
}

/**
 * Generic command line interface
 */
public class GenericCLI implements CustomCommandLine {
    @Override
    public boolean isActive(CommandLine commandLine);

    @Override
    public String getId();

    @Override
    public void addRunOptions(Options options);

    @Override
    public void addGeneralOptions(Options options);

    @Override
    public Configuration applyCommandLineOptionsToConfiguration(CommandLine commandLine);
}

/**
 * Parses command line arguments for Flink CLI
 */
public class CliFrontendParser {
    /**
     * Parses command line arguments
     * @param options Available options
     * @param args Arguments to parse
     * @param stopAtNonOptions Whether to stop parsing at non-options
     * @return Parsed CommandLine instance
     */
    public static CommandLine parse(Options options, String[] args, boolean stopAtNonOptions);

    /**
     * Gets options for run command
     * @return Options instance with run command options
     */
    public static Options getRunCommandOptions();

    /**
     * Gets options for cancel command
     * @return Options instance with cancel command options
     */
    public static Options getCancelCommandOptions();

    /**
     * Gets options for stop command
     * @return Options instance with stop command options
     */
    public static Options getStopCommandOptions();

    /**
     * Gets options for savepoint command
     * @return Options instance with savepoint command options
     */
    public static Options getSavepointCommandOptions();

    /**
     * Gets options for list command
     * @return Options instance with list command options
     */
    public static Options getListCommandOptions();
}

/**
 * Base class for command line option parsing
 */
public abstract class CommandLineOptions {
    /**
     * Creates command line options from parsed command line
     * @param cmdLine Parsed command line
     */
    protected CommandLineOptions(CommandLine cmdLine);
}

/**
 * Command line options for cancel operations
 */
public class CancelOptions extends CommandLineOptions {
    /**
     * Creates cancel options from command line
     * @param cmdLine Parsed command line
     */
    public CancelOptions(CommandLine cmdLine);

    /**
     * Gets the job ID to cancel
     * @return JobID instance
     */
    public JobID getJobId();
}

/**
 * Options for list operations
 */
public class ListOptions extends CommandLineOptions {
    /**
     * Creates list options from command line
     * @param cmdLine Parsed command line
     */
    public ListOptions(CommandLine cmdLine);

    /**
     * Checks if running jobs should be shown
     * @return true if showing running jobs
     */
    public boolean showRunning();

    /**
     * Checks if scheduled jobs should be shown
     * @return true if showing scheduled jobs
     */
    public boolean showScheduled();

    /**
     * Checks if all jobs should be shown
     * @return true if showing all jobs
     */
    public boolean showAll();
}

/**
 * Program-specific command line options
 */
public class ProgramOptions extends CommandLineOptions {
    /**
     * Creates program options from command line
     * @param cmdLine Parsed command line
     */
    public ProgramOptions(CommandLine cmdLine);

    /**
     * Gets the JAR file path
     * @return Path to JAR file
     */
    public String getJarFilePath();

    /**
     * Gets the entry point class name
     * @return Fully qualified class name
     */
    public String getEntryPointClassName();

    /**
     * Gets program arguments
     * @return Array of program arguments
     */
    public String[] getProgramArgs();

    /**
     * Gets additional classpaths
     * @return List of classpath URLs
     */
    public List<URL> getClasspaths();

    /**
     * Gets the parallelism setting
     * @return Parallelism value, -1 if not set
     */
    public int getParallelism();

    /**
     * Gets detached mode setting
     * @return true if running in detached mode
     */
    public boolean getDetachedMode();

    /**
     * Gets shutdown on attached exit setting
     * @return true if should shutdown on exit
     */
    public boolean isShutdownOnAttachedExit();
}

/**
 * Options for savepoint operations
 */
public class SavepointOptions extends CommandLineOptions {
    /**
     * Creates savepoint options from command line
     * @param cmdLine Parsed command line
     */
    public SavepointOptions(CommandLine cmdLine);

    /**
     * Gets the job ID for savepoint operation
     * @return JobID instance
     */
    public JobID getJobId();

    /**
     * Gets the savepoint path
     * @return Path to savepoint
     */
    public String getSavepointPath();

    /**
     * Checks if this is a dispose operation
     * @return true if disposing savepoint
     */
    public boolean isDispose();

    /**
     * Gets the target directory for savepoint
     * @return Target directory path
     */
    public String getTargetDirectory();
}

/**
 * Options for stop operations
 */
public class StopOptions extends CommandLineOptions {
    /**
     * Creates stop options from command line
     * @param cmdLine Parsed command line
     */
    public StopOptions(CommandLine cmdLine);

    /**
     * Gets the job ID to stop
     * @return JobID instance
     */
    public JobID getJobId();

    /**
     * Checks if savepoint flag is set
     * @return true if creating savepoint on stop
     */
    public boolean hasSavepointFlag();

    /**
     * Gets the target directory for savepoint on stop
     * @return Target directory path
     */
    public String getTargetDirectory();

    /**
     * Checks if should advance to end of event time
     * @return true if advancing to end of event time
     */
    public boolean shouldAdvanceToEndOfEventTime();
}

import org.apache.flink.client.cli.*;
import org.apache.commons.cli.CommandLine;

// Parse program options
String[] args = {"run", "-p", "4", "-c", "com.example.Main", "app.jar", "--input", "data"};
Options options = CliFrontendParser.getRunCommandOptions();
CommandLine cmdLine = CliFrontendParser.parse(options, args, true);

ProgramOptions programOpts = new ProgramOptions(cmdLine);
System.out.println("JAR file: " + programOpts.getJarFilePath());
System.out.println("Main class: " + programOpts.getEntryPointClassName());
System.out.println("Parallelism: " + programOpts.getParallelism());
System.out.println("Args: " + Arrays.toString(programOpts.getProgramArgs()));

// Parse cancel options
String[] cancelArgs = {"cancel", "a1b2c3d4e5f6"};
Options cancelOptions = CliFrontendParser.getCancelCommandOptions();
CommandLine cancelCmdLine = CliFrontendParser.parse(cancelOptions, cancelArgs, false);

CancelOptions cancelOpts = new CancelOptions(cancelCmdLine);
System.out.println("Job to cancel: " + cancelOpts.getJobId());

/**
 * Configuration options for Flink client
 */
public class ClientOptions {
    /**
     * Client retry period configuration option
     */
    public static final ConfigOption<String> CLIENT_RETRY_PERIOD;

    /**
     * Client timeout configuration option
     */
    public static final ConfigOption<Integer> CLIENT_TIMEOUT;
}

/**
 * Utilities for program options
 */
public class ProgramOptionsUtils {
    /**
     * Creates configuration from program options
     * @param programOptions Program options to convert
     * @return Configuration with program options applied
     */
    public static Configuration createConfigurationFromOptions(ProgramOptions programOptions);
}

/**
 * Utilities for handling dynamic properties
 */
public class DynamicPropertiesUtil {
    /**
     * Creates configuration from dynamic properties
     * @param dynamicProperties List of dynamic property strings (key=value format)
     * @return Configuration with dynamic properties applied
     */
    public static Configuration createConfigFromDynamicProperties(List<String> dynamicProperties);
}

/**
 * Access and manipulate execution configuration
 */
public class ExecutionConfigAccessor {
    /**
     * Creates ExecutionConfig from Configuration
     * @param configuration Flink configuration
     * @return ExecutionConfig instance
     */
    public static ExecutionConfig fromConfiguration(Configuration configuration);
}

import org.apache.flink.client.cli.ProgramOptionsUtils;
import org.apache.flink.client.cli.DynamicPropertiesUtil;

// Create configuration from program options
Configuration config = ProgramOptionsUtils.createConfigurationFromOptions(programOptions);

// Apply dynamic properties
List<String> dynamicProps = Arrays.asList(
    "parallelism.default=8",
    "taskmanager.memory.process.size=2g"
);
Configuration dynamicConfig = DynamicPropertiesUtil.createConfigFromDynamicProperties(dynamicProps);

// Merge configurations
config.addAll(dynamicConfig);

// Get execution config
ExecutionConfig execConfig = ExecutionConfigAccessor.fromConfiguration(config);

/**
 * Exception for command line argument errors
 */
public class CliArgsException extends Exception {
    /**
     * Creates exception with message
     * @param message Error message
     */
    public CliArgsException(String message);

    /**
     * Creates exception with message and cause
     * @param message Error message
     * @param cause Root cause throwable
     */
    public CliArgsException(String message, Throwable cause);
}

public class CommandLine {
    // Apache Commons CLI CommandLine class
    public String[] getArgs();
    public String getOptionValue(String opt);
    public boolean hasOption(String opt);
    public String[] getOptionValues(String opt);
}

public class Options {
    // Apache Commons CLI Options class
    public Options addOption(String opt, boolean hasArg, String description);
    public Options addOption(String opt, String longOpt, boolean hasArg, String description);
}

public interface ConfigOption<T> {
    String key();
    T defaultValue();
    Class<T> getClazz();
}

public class ExecutionConfig implements Serializable {
    public void setParallelism(int parallelism);
    public int getParallelism();
    public void setMaxParallelism(int maxParallelism);
    public int getMaxParallelism();
}