1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/java/copy-image-resizer/src/cz/frantovo/copyImageResizer/cli/CLIParser.java Sun Nov 16 21:59:13 2014 +0100
1.3 @@ -0,0 +1,139 @@
1.4 +/**
1.5 + * copy-image-resizer
1.6 + * Copyright © 2014 František Kučera (frantovo.cz)
1.7 + *
1.8 + * This program is free software: you can redistribute it and/or modify
1.9 + * it under the terms of the GNU General Public License as published by
1.10 + * the Free Software Foundation, either version 3 of the License, or
1.11 + * (at your option) any later version.
1.12 + *
1.13 + * This program is distributed in the hope that it will be useful,
1.14 + * but WITHOUT ANY WARRANTY; without even the implied warranty of
1.15 + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
1.16 + * GNU General Public License for more details.
1.17 + *
1.18 + * You should have received a copy of the GNU General Public License
1.19 + * along with this program. If not, see <http://www.gnu.org/licenses/>.
1.20 + */
1.21 +package cz.frantovo.copyImageResizer.cli;
1.22 +
1.23 +import java.io.File;
1.24 +import java.util.Arrays;
1.25 +import java.util.Collection;
1.26 +
1.27 +/**
1.28 + *
1.29 + * @author Ing. František Kučera (frantovo.cz)
1.30 + */
1.31 +public class CLIParser {
1.32 +
1.33 + public CLIOptions parseOptions(String[] args) throws CLIParserException {
1.34 + CLIOptions options = new CLIOptions();
1.35 +
1.36 + for (int i = 0; i < args.length; i++) {
1.37 + String arg = args[i];
1.38 +
1.39 + boolean matches = false;
1.40 +
1.41 + for (Token t : Token.values()) {
1.42 + if (t.matches(arg)) {
1.43 + int parsedArgs = t.parse(args, i, options);
1.44 + i = i + parsedArgs;
1.45 + matches = true;
1.46 + }
1.47 + }
1.48 +
1.49 + if (!matches) {
1.50 + throw new CLIParserException("Unknown option: " + arg);
1.51 + }
1.52 + }
1.53 +
1.54 + return options;
1.55 + }
1.56 +
1.57 + private static String fetchNext(String[] args, int index) throws CLIParserException {
1.58 + if (index < args.length) {
1.59 + return args[index];
1.60 + } else {
1.61 + throw new CLIParserException("Expecting value for option: " + args[index - 1]);
1.62 + }
1.63 + }
1.64 +
1.65 + private static enum Token {
1.66 +
1.67 + INPUT_DIR("--input-dir") { // bash-completion: option
1.68 + @Override
1.69 + public int parse(String[] args, int index, CLIOptions options) throws CLIParserException {
1.70 + int originalIndex = index;
1.71 + String name = fetchNext(args, ++index);
1.72 + options.setInput(new File(name));
1.73 + return index - originalIndex;
1.74 + }
1.75 + },
1.76 + OUTPUT_DIR("--output-dir") { // bash-completion: option
1.77 + @Override
1.78 + public int parse(String[] args, int index, CLIOptions options) throws CLIParserException {
1.79 + int originalIndex = index;
1.80 + String name = fetchNext(args, ++index);
1.81 + options.setOutput(new File(name));
1.82 + return index - originalIndex;
1.83 + }
1.84 + },
1.85 + SIZE("--size") { // bash-completion: option
1.86 + @Override
1.87 + public int parse(String[] args, int index, CLIOptions options) throws CLIParserException {
1.88 + int originalIndex = index;
1.89 + int width = parseInt(fetchNext(args, ++index));
1.90 + int height = parseInt(fetchNext(args, ++index));
1.91 + String directory = width + "x" + height;
1.92 + options.addSize(new CLIOptions.SizeSpecification(width, height, directory));
1.93 + return index - originalIndex;
1.94 + }
1.95 + },
1.96 + SIZE_NAMED("--size-named") { // bash-completion: option
1.97 + @Override
1.98 + public int parse(String[] args, int index, CLIOptions options) throws CLIParserException {
1.99 + int originalIndex = index;
1.100 + int width = parseInt(fetchNext(args, ++index));
1.101 + int height = parseInt(fetchNext(args, ++index));
1.102 + String directory = fetchNext(args, ++index);
1.103 + options.addSize(new CLIOptions.SizeSpecification(width, height, directory));
1.104 + return index - originalIndex;
1.105 + }
1.106 + };
1.107 +
1.108 + private final Collection<String> options;
1.109 +
1.110 + private Token(String... options) {
1.111 + this.options = Arrays.asList(options);
1.112 + }
1.113 +
1.114 + /**
1.115 + * @param option e.g. „--input-file“
1.116 + * @return whether option is this token
1.117 + */
1.118 + public boolean matches(String option) {
1.119 + return options.contains(option);
1.120 + }
1.121 +
1.122 + private static int parseInt(String number) throws CLIParserException {
1.123 + try {
1.124 + return Integer.parseInt(number);
1.125 + } catch (Exception e) {
1.126 + throw new CLIParserException("Unable to parse integer: " + number, e);
1.127 + }
1.128 + }
1.129 +
1.130 + /**
1.131 + * Parse String arguments and fill values into the options object.
1.132 + *
1.133 + * @param args CLI arguments
1.134 + * @param index index of the option matched by this token, like „--input-file“
1.135 + * @param options object to be filled
1.136 + * @return number of parsed arguments – if option has no arguments (just boolean flag),
1.137 + * return 0, otherwise return positive integer: number of eaten arguments.
1.138 + * @throws CLIParserException
1.139 + */
1.140 + public abstract int parse(String[] args, int index, CLIOptions options) throws CLIParserException;
1.141 + }
1.142 +}