henplus.AbstractCommand.java Source code

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Here is the source code for henplus.AbstractCommand.java

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/*
 * This is free software, licensed under the Gnu Public License (GPL) get a copy from <http://www.gnu.org/licenses/gpl.html>
 * 
 * author: Henner Zeller <H.Zeller@acm.org>
 */
package henplus;

import java.util.Collection;
import java.util.Collections;
import java.util.Iterator;
import java.util.StringTokenizer;

import org.apache.commons.cli.CommandLine;
import org.apache.commons.cli.Option;

/**
 * Implementation of a Command with default settings. Override what is necessary in your Command. It makes sense to derive plug-ins
 * from this AbstractCommand - this makes the plug-in more robust with regard to newly added methods.
 * 
 * @author Henner Zeller
 */
public abstract class AbstractCommand implements Command {

    // no description by default.
    @Override
    public String getShortDescription() {
        return null;
    }

    @Override
    public String getLongDescription(final String cmd) {
        final Collection<Option> handledCommandLineOptions = getHandledCommandLineOptions();
        if (handledCommandLineOptions != null && handledCommandLineOptions.size() > 0) {
            final StringBuilder sb = new StringBuilder("\tRecognized options are:\n");
            for (final Option option : handledCommandLineOptions) {
                sb.append(String.format("\t -%s %s\n", option.getOpt(), option.getDescription()));
            }
            return sb.toString();
        }
        return null;
    }

    @Override
    public String getSynopsis(final String cmd) {
        return null;
    }

    // All commands are completed by default.
    @Override
    public boolean participateInCommandCompletion() {
        return true;
    }

    // no completion support by the commmand
    @Override
    public Iterator<String> complete(final CommandDispatcher disp, final String partialCommand,
            final String lastWord) {
        return null;
    }

    @Override
    public void shutdown() { /* don't care */
    }

    // the simple commands are always complete on newline or semicolon
    @Override
    public boolean isComplete(final String command) {
        return true;
    }

    @Override
    public boolean requiresValidSession(final String cmd) {
        return true;
    }

    /**
     * convenience method: returns the number of elements in this string, separated by whitespace.
     */
    protected int argumentCount(final String command) {
        return new StringTokenizer(command).countTokens();
    }

    /**
     * Override this method if you want to register command-specific options.
     * 
     * @param r
     */
    @Override
    public Collection<Option> getHandledCommandLineOptions() {
        return Collections.emptyList();
    }

    @Override
    public void handleCommandline(final CommandLine line) {

    }
}

/*
 * Local variables: c-basic-offset: 4 compile-command:
 * "ant -emacs -find build.xml" End:
 */