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package io.dropwizard.core.cli;

import io.dropwizard.core.setup.Bootstrap;
import net.sourceforge.argparse4j.inf.Namespace;
import net.sourceforge.argparse4j.inf.Subparser;

/**
 * A basic CLI command.
 */
public abstract class Command {
    private final String name;
    private final String description;

    /**
     * Create a new command with the given name and description.
     *
     * @param name        the name of the command, used for command line invocation
     * @param description a description of the command's purpose
     */
    protected Command(String name, String description) {
        this.name = name;
        this.description = description;
    }

    /**
     * Returns the command's name.
     *
     * @return the command's name
     */
    public final String getName() {
        return name;
    }

    /**
     * Returns the command's description.
     *
     * @return the command's description
     */
    public final String getDescription() {
        return description;
    }

    /**
     * Configure the command's {@link Subparser}.
     *
     * @param subparser the {@link Subparser} specific to the command
     */
    public abstract void configure(Subparser subparser);

    /**
     * Executes when the user runs this specific command.
     *
     * @param bootstrap the bootstrap bootstrap
     * @param namespace the parsed command line namespace
     * @throws Exception if something goes wrong
     */
    public abstract void run(Bootstrap bootstrap, Namespace namespace) throws Exception;

    /**
     * Method is called if there is an issue parsing configuration, setting up the
     * environment, or running the command itself. The default is printing the stacktrace
     * to facilitate debugging, but can be customized per command.
     *
     * @param cli contains the streams for stdout and stderr
     * @param namespace the parsed arguments from the commandline
     * @param e The exception that was thrown when setting up or running the command
     */
    public void onError(Cli cli, Namespace namespace, Throwable e) {
        e.printStackTrace(cli.getStdErr());
    }
}