nl.toolforge.karma.console.CommandRenderer.java Source code

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Here is the source code for nl.toolforge.karma.console.CommandRenderer.java

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/*
Karma CLI - Command Line Interface for the Karma application
Copyright (C) 2004  Toolforge <www.toolforge.nl>
    
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
    
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
Lesser General Public License for more details.
    
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/
package nl.toolforge.karma.console;

import nl.toolforge.core.util.lang.NiftyStringUtils;
import nl.toolforge.karma.core.cmd.CommandDescriptor;
import nl.toolforge.karma.core.cmd.CommandException;
import nl.toolforge.karma.core.cmd.CommandFactory;
import nl.toolforge.karma.core.cmd.CommandLoadException;
import org.apache.commons.cli.Option;
import org.apache.commons.lang.StringUtils;

import java.util.Collection;
import java.util.Hashtable;
import java.util.Iterator;
import java.util.Map;

public final class CommandRenderer {

    public static final int COMMAND_FILL = 40;
    public static final int OPTION_FILL = 50;

    public static String commands = null;

    private static Map helpCache = null;

    private CommandRenderer() {
    }

    /**
     * Provides a <code>String</code> view on <code>command</code>.
     *
     * @param commandName The name (or an alias) for the command.
     * @return A <code>String</code> with help info for the command.
     */
    public static String renderCommand(String commandName) throws CommandLoadException, CommandException {

        if (helpCache == null) {
            helpCache = new Hashtable();
        } else {
            if (helpCache.containsKey(commandName)) {
                return (String) helpCache.get(commandName);
            }
        }

        CommandDescriptor descriptor = CommandFactory.getInstance().getCommandDescriptor(commandName);

        if (descriptor == null) {
            throw new CommandException(CommandException.UNKNOWN_COMMAND, new Object[] { commandName });
        }

        Collection optionsCollection = descriptor.getOptions().getOptions();
        Option[] options = (Option[]) optionsCollection.toArray(new Option[optionsCollection.size()]);

        String cachedItem = printCommand(descriptor, options, true, true).toString();
        helpCache.put(commandName, cachedItem);

        return cachedItem;
    }

    /**
     * Provides a <code>String</code> view on all commands, nicely rendered.
     *
     * @param commandDescriptors
     *   A <code>Collection</code> with all command descriptors for the commands applicable to the Karma runtime.
     *
     * @return
     *   A <code>String</code> with all command usages, rendered much like what a shell (like <code>sh</code>) would
     *   provide.
     */
    public static String renderedCommands(Collection commandDescriptors) {

        if (commands == null) {

            StringBuffer buffer = new StringBuffer();

            for (Iterator i = commandDescriptors.iterator(); i.hasNext();) {

                CommandDescriptor descriptor = (CommandDescriptor) i.next();

                Collection optionsCollection = descriptor.getOptions().getOptions();
                Option[] options = (Option[]) optionsCollection.toArray(new Option[optionsCollection.size()]);

                buffer.append(printCommand(descriptor, options, false, false));
            }
            commands = buffer.toString();
        }

        return commands;
    }

    private static StringBuffer printCommand(CommandDescriptor descriptor, Option[] options, boolean showOptions,
            boolean showHelp) {

        StringBuffer buffer = new StringBuffer();
        String commandNameAlias = descriptor.getName() + " (" + descriptor.getAlias() + ")";

        buffer.append(commandNameAlias).append(StringUtils.repeat(" ", COMMAND_FILL - commandNameAlias.length()));
        if (!showOptions) {
            buffer.append(descriptor.getDescription());
        }
        buffer.append("\n");

        if (showOptions) {
            for (int j = 0; j < options.length; j++) {

                Option o = options[j];

                String leftPadding = "   ";

                buffer.append(leftPadding).append("-" + o.getOpt()).append(", --" + o.getLongOpt());

                String args = "";
                if (o.hasArg()) {
                    args = " <".concat(o.getArgName()).concat(">");
                }

                // todo when the commands are described with too much of text, then FILL will run out of count ...
                //
                buffer.append(args.concat(StringUtils.repeat(" ", OPTION_FILL - (o.getLongOpt() + args).length())));
                buffer.append(leftPadding);
                if (!o.isRequired()) {
                    buffer.append("(Optional) ");
                }
                buffer.append(o.getDescription());
                buffer.append("\n");
            }
        }

        if (showHelp) {
            buffer.append("\n");

            String trimmed = NiftyStringUtils.deleteWhiteSpaceExceptOne(descriptor.getHelp());
            String[] split = NiftyStringUtils.split(trimmed, " ", 120);
            String joined = StringUtils.join(split, "\n");

            buffer.append(joined);
            buffer.append("\n");
        }

        return buffer;
    }
}