Apache Flink Clients

// CLI Frontend for command-line operations
import org.apache.flink.client.cli.CliFrontend;

// Core cluster client interface
import org.apache.flink.client.program.ClusterClient;

// Program packaging and execution
import org.apache.flink.client.program.PackagedProgram;

// Deployment management
import org.apache.flink.client.deployment.ClusterDescriptor;
import org.apache.flink.client.deployment.ClusterClientFactory;

// Application mode deployment
import org.apache.flink.client.deployment.application.ApplicationRunner;
import org.apache.flink.client.deployment.application.ApplicationConfiguration;

import org.apache.flink.client.program.ClusterClient;
import org.apache.flink.client.program.PackagedProgram;
import org.apache.flink.client.program.rest.RestClusterClient;
import org.apache.flink.client.program.rest.RestClusterClientConfiguration;
import org.apache.flink.configuration.Configuration;
import org.apache.flink.configuration.RestOptions;

// Create cluster client configuration
Configuration config = new Configuration();
config.setString(RestOptions.ADDRESS, "localhost");
config.setInteger(RestOptions.PORT, 8081);

// Create REST cluster client
RestClusterClientConfiguration clientConfig = 
    RestClusterClientConfiguration.fromConfiguration(config);
try (ClusterClient<?> client = new RestClusterClient<>(clientConfig, "default")) {
    
    // Package and submit a job
    PackagedProgram program = PackagedProgram.newBuilder()
        .setJarFile(new File("/path/to/job.jar"))
        .setArguments(new String[]{"--input", "input.txt"})
        .build();
    
    // Submit job to cluster
    JobID jobId = ClientUtils.executeProgram(
        new DefaultExecutorServiceLoader(), 
        config, 
        program, 
        false, 
        false
    ).getJobID();
    
    System.out.println("Submitted job: " + jobId);
}

public class CliFrontend {
    public static void main(String[] args);
    public int parseAndRun(String[] args);
}

public interface ClusterClient<T> extends AutoCloseable {
    T getClusterId();
    Configuration getFlinkConfiguration();
    CompletableFuture<Collection<JobStatusMessage>> listJobs() throws Exception;
    CompletableFuture<JobID> submitJob(ExecutionPlan executionPlan);
    CompletableFuture<JobStatus> getJobStatus(JobID jobId);
    String getWebInterfaceURL();
    void shutDownCluster();
}

public class PackagedProgram implements AutoCloseable {
    public static Builder newBuilder();
    public Class<?> getMainClass() throws ProgramInvocationException;
    public String[] getArguments();
    public void invokeInteractiveModeForExecution() throws ProgramInvocationException;
}

public interface ClusterDescriptor<T> extends AutoCloseable {
    ClusterClientProvider<T> retrieve(T clusterId) throws ClusterRetrieveException;
    ClusterClientProvider<T> deploySessionCluster(ClusterSpecification clusterSpecification) 
        throws ClusterDeploymentException;
}

public interface ClusterClientFactory<T> {
    boolean isCompatibleWith(Configuration configuration);
    ClusterDescriptor<T> createClusterDescriptor(Configuration configuration);
}

public interface ApplicationRunner {
    CompletableFuture<Void> run(
        DispatcherGateway dispatcherGateway,
        ScheduledExecutor scheduledExecutor,
        ApplicationConfiguration applicationConfiguration
    );
}

public class ApplicationConfiguration {
    public static Builder fromConfiguration(Configuration configuration);
    public String[] getProgramArguments();
    public String[] getApplicationArgs();
}

public interface ArtifactFetcher {
    CompletableFuture<File> fetch(
        URI uri,
        Configuration flinkConf,
        File targetDir,
        @Nullable String filename
    ) throws Exception;
}

public class ArtifactFetchManager {
    public static ArtifactFetchManager fromConfiguration(Configuration configuration);
    public CompletableFuture<File> fetchArtifact(URI uri, File targetDir) throws Exception;
}

// Core types used across multiple capabilities
public class JobID extends AbstractID {
    public static JobID generate();
}

public enum JobStatus {
    CREATED, RUNNING, FAILING, FAILED, CANCELLING, CANCELED, FINISHED, RESTARTING, SUSPENDED, RECONCILING
}

public class JobStatusMessage {
    public JobID getJobId();
    public String getJobName();
    public JobStatus getJobState();
    public long getStartTime();
}

public class ClusterSpecification {
    public int getMasterMemoryMB();
    public int getTaskManagerMemoryMB();
    public int getNumberTaskManagers();
}

// Exception types
public class ProgramInvocationException extends FlinkException {
    public ProgramInvocationException(String message);
    public ProgramInvocationException(String message, Throwable cause);
}

public class ClusterDeploymentException extends FlinkException {
    public ClusterDeploymentException(String message);
    public ClusterDeploymentException(String message, Throwable cause);
}

public class ClusterRetrieveException extends FlinkException {
    public ClusterRetrieveException(String message);
    public ClusterRetrieveException(String message, Throwable cause);
}