| /** |
| * 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.distributedlog.tools; |
| |
| import org.apache.bookkeeper.util.ReflectionUtils; |
| import org.apache.commons.cli.BasicParser; |
| import org.apache.commons.cli.CommandLine; |
| import org.apache.commons.cli.HelpFormatter; |
| import org.apache.commons.cli.Options; |
| import org.apache.commons.cli.ParseException; |
| |
| import java.util.Map; |
| import java.util.TreeMap; |
| |
| /** |
| * A Tool Framework |
| */ |
| public abstract class Tool { |
| |
| /** |
| * Interface of a command to run in a tool. |
| */ |
| protected interface Command { |
| String getName(); |
| String getDescription(); |
| int runCmd(String[] args) throws Exception; |
| void printUsage(); |
| } |
| |
| /** |
| * {@link org.apache.commons.cli.Options} based command. |
| */ |
| protected abstract static class OptsCommand implements Command { |
| |
| /** |
| * @return options used by this command. |
| */ |
| protected abstract Options getOptions(); |
| |
| /** |
| * @return usage of this command. |
| */ |
| protected String getUsage() { |
| return cmdName + " [options]"; |
| } |
| |
| /** |
| * Run given command line <i>commandLine</i>. |
| * |
| * @param commandLine |
| * command line to run. |
| * @return return code of this command. |
| * @throws Exception |
| */ |
| protected abstract int runCmd(CommandLine commandLine) throws Exception; |
| |
| protected String cmdName; |
| protected String description; |
| |
| protected OptsCommand(String name, String description) { |
| this.cmdName = name; |
| this.description = description; |
| } |
| |
| @Override |
| public String getName() { |
| return cmdName; |
| } |
| |
| @Override |
| public String getDescription() { |
| return description; |
| } |
| |
| @Override |
| public int runCmd(String[] args) throws Exception { |
| try { |
| BasicParser parser = new BasicParser(); |
| CommandLine cmdline = parser.parse(getOptions(), args); |
| return runCmd(cmdline); |
| } catch (ParseException e) { |
| printUsage(); |
| return -1; |
| } |
| } |
| |
| @Override |
| public void printUsage() { |
| HelpFormatter helpFormatter = new HelpFormatter(); |
| println(cmdName + ": " + getDescription()); |
| helpFormatter.printHelp(getUsage(), getOptions()); |
| } |
| } |
| |
| public class HelpCommand implements Command { |
| |
| @Override |
| public String getName() { |
| return "help"; |
| } |
| |
| @Override |
| public String getDescription() { |
| return "describe the usage of this tool or its sub-commands."; |
| } |
| |
| @Override |
| public int runCmd(String[] args) throws Exception { |
| if (args.length == 0) { |
| printToolUsage(); |
| return -1; |
| } |
| String cmdName = args[0]; |
| Command command = commands.get(cmdName); |
| if (null == command) { |
| System.err.println("Unknown command " + cmdName); |
| printToolUsage(); |
| return -1; |
| } |
| command.printUsage(); |
| println(""); |
| return 0; |
| } |
| |
| @Override |
| public void printUsage() { |
| println(getName() + ": " + getDescription()); |
| println(""); |
| println("usage: " + getName() + " <command>"); |
| } |
| } |
| |
| // Commands managed by a tool |
| protected final Map<String, Command> commands = |
| new TreeMap<String, Command>(); |
| |
| protected Tool() { |
| addCommand(new HelpCommand()); |
| } |
| |
| /** |
| * @return tool name. |
| */ |
| protected abstract String getName(); |
| |
| /** |
| * Add a command in this tool. |
| * |
| * @param command |
| * command to run in this tool. |
| */ |
| protected void addCommand(Command command) { |
| commands.put(command.getName(), command); |
| } |
| |
| /** |
| * Print a message in this tool. |
| * |
| * @param msg |
| * message to print |
| */ |
| protected static void println(String msg) { |
| System.out.println(msg); |
| } |
| |
| /** |
| * print tool usage. |
| */ |
| protected void printToolUsage() { |
| println("Usage: " + getName() + " <command>"); |
| println(""); |
| int maxKeyLength = 0; |
| for (String key : commands.keySet()) { |
| if (key.length() > maxKeyLength) { |
| maxKeyLength = key.length(); |
| } |
| } |
| maxKeyLength += 2; |
| for (Map.Entry<String, Command> entry : commands.entrySet()) { |
| StringBuilder spacesBuilder = new StringBuilder(); |
| int numSpaces = maxKeyLength - entry.getKey().length(); |
| for (int i = 0; i < numSpaces; i++) { |
| spacesBuilder.append(" "); |
| } |
| println("\t" + entry.getKey() + spacesBuilder.toString() + ": " + entry.getValue().getDescription()); |
| } |
| println(""); |
| } |
| |
| public int run(String[] args) throws Exception { |
| if (args.length <= 0) { |
| printToolUsage(); |
| return -1; |
| } |
| String cmdName = args[0]; |
| Command cmd = commands.get(cmdName); |
| if (null == cmd) { |
| System.err.println("ERROR: Unknown command " + cmdName); |
| printToolUsage(); |
| return -1; |
| } |
| // prepare new args |
| String[] newArgs = new String[args.length - 1]; |
| System.arraycopy(args, 1, newArgs, 0, newArgs.length); |
| return cmd.runCmd(newArgs); |
| } |
| |
| public static void main(String args[]) { |
| int rc = -1; |
| if (args.length <= 0) { |
| System.err.println("No tool to run."); |
| System.err.println(""); |
| System.err.println("Usage : Tool <tool_class_name> <options>"); |
| System.exit(-1); |
| } |
| String toolClass = args[0]; |
| try { |
| Tool tool = ReflectionUtils.newInstance(toolClass, Tool.class); |
| String[] newArgs = new String[args.length - 1]; |
| System.arraycopy(args, 1, newArgs, 0, newArgs.length); |
| rc = tool.run(newArgs); |
| } catch (Throwable t) { |
| System.err.println("Fail to run tool " + toolClass + " : "); |
| t.printStackTrace(); |
| } |
| System.exit(rc); |
| } |
| } |