001/* 002 * Copyright 2012-2016 the original author or authors. 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * http://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 */ 016 017package org.springframework.boot.cli.command.core; 018 019import java.util.ArrayList; 020import java.util.Collections; 021import java.util.List; 022 023import org.springframework.boot.cli.command.AbstractCommand; 024import org.springframework.boot.cli.command.Command; 025import org.springframework.boot.cli.command.CommandRunner; 026import org.springframework.boot.cli.command.options.OptionHelp; 027import org.springframework.boot.cli.command.status.ExitStatus; 028import org.springframework.boot.cli.util.Log; 029 030/** 031 * Internal {@link Command} to provide hints for shell auto-completion. Expects to be 032 * called with the current index followed by a list of arguments already typed. 033 * 034 * @author Phillip Webb 035 */ 036public class HintCommand extends AbstractCommand { 037 038 private final CommandRunner commandRunner; 039 040 public HintCommand(CommandRunner commandRunner) { 041 super("hint", "Provides hints for shell auto-completion"); 042 this.commandRunner = commandRunner; 043 } 044 045 @Override 046 public ExitStatus run(String... args) throws Exception { 047 try { 048 int index = (args.length == 0 ? 0 : Integer.valueOf(args[0]) - 1); 049 List<String> arguments = new ArrayList<String>(args.length); 050 for (int i = 2; i < args.length; i++) { 051 arguments.add(args[i]); 052 } 053 String starting = ""; 054 if (index < arguments.size()) { 055 starting = arguments.remove(index); 056 } 057 if (index == 0) { 058 showCommandHints(starting); 059 } 060 else if (!arguments.isEmpty() && (starting.length() > 0)) { 061 String command = arguments.remove(0); 062 showCommandOptionHints(command, Collections.unmodifiableList(arguments), 063 starting); 064 } 065 } 066 catch (Exception ex) { 067 // Swallow and provide no hints 068 return ExitStatus.ERROR; 069 } 070 return ExitStatus.OK; 071 } 072 073 private void showCommandHints(String starting) { 074 for (Command command : this.commandRunner) { 075 if (isHintMatch(command, starting)) { 076 Log.info(command.getName() + " " + command.getDescription()); 077 } 078 } 079 } 080 081 private boolean isHintMatch(Command command, String starting) { 082 if (command instanceof HintCommand) { 083 return false; 084 } 085 return command.getName().startsWith(starting) 086 || (this.commandRunner.isOptionCommand(command) 087 && ("--" + command.getName()).startsWith(starting)); 088 } 089 090 private void showCommandOptionHints(String commandName, 091 List<String> specifiedArguments, String starting) { 092 Command command = this.commandRunner.findCommand(commandName); 093 if (command != null) { 094 for (OptionHelp help : command.getOptionsHelp()) { 095 if (!alreadyUsed(help, specifiedArguments)) { 096 for (String option : help.getOptions()) { 097 if (option.startsWith(starting)) { 098 Log.info(option + " " + help.getUsageHelp()); 099 } 100 } 101 } 102 } 103 } 104 } 105 106 private boolean alreadyUsed(OptionHelp help, List<String> specifiedArguments) { 107 for (String argument : specifiedArguments) { 108 if (help.getOptions().contains(argument)) { 109 return true; 110 } 111 } 112 return false; 113 } 114 115}