Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You under the Apache License, Version 2.0 * (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.apache.jackrabbit.standalone.cli.info; import java.io.PrintWriter; import java.util.Collection; import java.util.Iterator; import java.util.MissingResourceException; import java.util.ResourceBundle; import org.apache.commons.chain.Command; import org.apache.commons.chain.Context; import org.apache.commons.cli.HelpFormatter; import org.apache.jackrabbit.standalone.cli.AbstractParameter; import org.apache.jackrabbit.standalone.cli.Argument; import org.apache.jackrabbit.standalone.cli.CommandException; import org.apache.jackrabbit.standalone.cli.CommandHelper; import org.apache.jackrabbit.standalone.cli.CommandLine; import org.apache.jackrabbit.standalone.cli.CommandLineFactory; import org.apache.jackrabbit.standalone.cli.Flag; import org.apache.jackrabbit.standalone.cli.Option; /** * Show available <code>Command</code>s. If a <code>Command</code> is * specified it will show its description, usage and parameters. */ public class Help implements Command { /** bundle */ private static ResourceBundle bundle = CommandHelper.getBundle(); /** Command factory */ private CommandLineFactory factory = CommandLineFactory.getInstance(); /** Help formatter */ private HelpFormatter hf = new HelpFormatter(); /** command key */ private String commandKey = "command"; /** * {@inheritDoc} */ public boolean execute(Context ctx) throws Exception { String command = (String) ctx.get(this.commandKey); PrintWriter out = CommandHelper.getOutput(ctx); out.println(); if (command == null) { helpAll(ctx); } else { helpCommand(ctx); } return false; } /** * Writes help for all the commands * @param ctx * the current working <code>Context</code> * @throws CommandException */ private void helpAll(Context ctx) throws CommandException { PrintWriter out = CommandHelper.getOutput(ctx); Collection descriptors = factory.getCommandLines(); Iterator iter = descriptors.iterator(); // Tab position int tabPos = 20; while (iter.hasNext()) { CommandLine desc = (CommandLine) iter.next(); if (desc.getName().length() > tabPos) { tabPos = desc.getName().length() + 1; } } iter = descriptors.iterator(); while (iter.hasNext()) { CommandLine desc = (CommandLine) iter.next(); StringBuffer buf = new StringBuffer(desc.getName()); buf.setLength(tabPos); for (int i = desc.getName().length(); i < buf.length(); i++) { buf.setCharAt(i, ' '); } buf.append(desc.getLocalizedDescription()); hf.printWrapped(out, 70, tabPos, buf.toString()); } } /** * Writes detailed help for the given command * @param ctx * the current working <code>Context</code> * @throws CommandException */ private void helpCommand(Context ctx) throws CommandException { PrintWriter out = CommandHelper.getOutput(ctx); String cmdName = (String) ctx.get(this.commandKey); CommandLine desc = factory.getCommandLine(cmdName); out.println(getString(bundle, "word.description") + ": "); out.println(desc.getLocalizedDescription()); out.println(); // Usage out.print(getString(bundle, "word.usage") + ":"); out.print(desc.getName() + " "); // Arguments Iterator iter = desc.getArguments().values().iterator(); while (iter.hasNext()) { Argument arg = (Argument) iter.next(); out.print("<" + arg.getLocalizedArgName() + "> "); } // Options iter = desc.getOptions().values().iterator(); while (iter.hasNext()) { Option arg = (Option) iter.next(); out.print("-" + arg.getName() + " <" + arg.getLocalizedArgName() + "> "); } // flags iter = desc.getFlags().values().iterator(); while (iter.hasNext()) { Flag arg = (Flag) iter.next(); out.print("-" + arg.getName() + " "); } out.println(); // Alias if (desc.getAlias().size() > 0) { out.print(getString(bundle, "word.alias") + ":"); iter = desc.getAlias().iterator(); while (iter.hasNext()) { out.print((String) iter.next() + " "); } out.println(); } out.println(); // Arguments details if (desc.getArguments().size() > 0) { out.println("<" + getString(bundle, "word.arguments") + ">"); printParam(ctx, desc.getArguments().values()); } // Options details if (desc.getOptions().values().size() > 0) { out.println(); out.println("<" + getString(bundle, "word.options") + ">"); printParam(ctx, desc.getOptions().values()); } // flag details if (desc.getFlags().values().size() > 0) { out.println(); out.println("<" + getString(bundle, "word.flags") + ">"); printParam(ctx, desc.getFlags().values()); } } /** * @param ctx * the current working <code>Context</code> * @param params * the parameters */ private void printParam(Context ctx, Collection params) { int[] width = new int[] { 10, 10, 10, 40 }; String[] header = new String[] { getString(bundle, "word.name"), getString(bundle, "word.argument"), getString(bundle, "word.required"), getString(bundle, "word.description") }; PrintHelper.printRow(ctx, width, header); PrintHelper.printSeparatorRow(ctx, width, '-'); Iterator iter = params.iterator(); while (iter.hasNext()) { AbstractParameter p = (AbstractParameter) iter.next(); String[] item = new String[] { p.getName(), p.getLocalizedArgName(), Boolean.toString(p.isRequired()), p.getLocalizedDescription() }; PrintHelper.printRow(ctx, width, item); } } /** * @return the command key */ public String getCommandKey() { return commandKey; } /** * @param commandKey * the command key to set */ public void setCommandKey(String commandKey) { this.commandKey = commandKey; } private String getString(ResourceBundle bundle, String key) { try { return bundle.getString(key); } catch (MissingResourceException e) { return "not available"; } } }