com.github.rvesse.airline.examples.simple.Simple Maven / Gradle / Ivy

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Provides a variety of examples of using Airline
There is a newer version: 3.0.0
/**
 * Copyright (C) 2010-16 the original author or authors.
 *
 * Licensed 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 com.github.rvesse.airline.examples.simple;

import java.util.List;

import javax.inject.Inject;

import org.apache.commons.lang3.StringUtils;

import com.github.rvesse.airline.HelpOption;
import com.github.rvesse.airline.annotations.Arguments;
import com.github.rvesse.airline.annotations.Command;
import com.github.rvesse.airline.annotations.Option;
import com.github.rvesse.airline.examples.ExampleExecutor;
import com.github.rvesse.airline.examples.ExampleRunnable;

/**
 * A simple example that demonstrates most of the basic concepts
 * 
 * We use the {@link Command} annotation to indicate that a class is going to
 * represent a command and then the {@link Option} annotation to indicate fields
 * whose values should be populated by options
 * 
 *
 */
@Command(name = "simple", description = "A simple example command")
public class Simple implements ExampleRunnable {

    /**
     * The special {@link HelpOption} provides a {@code -h} and {@code --help}
     * option that can be used to request that help be shown.
     * 
     * Developers need to check the {@link HelpOption#showHelpIfRequested()}
     * method which will display help if requested and return {@code true} if
     * the user requested the help
     * 
     */
    @Inject
    private HelpOption help;

    @Option(name = { "-f", "--flag" }, description = "An option that requires no arguments")
    private boolean flag = false;

    /**
     * Here we declare an option that requires a value by using the
     * {@code arity} field of the {@link Option} annotation
     */
    @Option(name = { "-n", "--name" }, title = "Name", arity = 1, description = "An option that takes an argument")
    private String name;

    /**
     * As we declare this field to be of type {@code int} Airline will ensure
     * that the value passed to this option can be converted to an integer and
     * throws an error if this is not possible
     */
    @Option(name = { "--number" }, title = "Number", arity = 1, description = "An option that takes a numeric argument")
    private int number;

    /**
     * The {@link Arguments} annotation allows commands to take in additional
     * arbitrary arguments
     */
    @Arguments
    private List args;

    public static void main(String[] args) {
        ExampleExecutor.executeSingleCommand(Simple.class, args);
    }

    @Override
    public int run() {
        if (help.showHelpIfRequested())
            return 0;
        System.out.println("Flag was " + (this.flag ? "set" : "not set"));
        System.out.println("Name was " + this.name);
        System.out.println("Number was " + this.number);
        if (args != null)
            System.out.println("Arguments were " + StringUtils.join(args, ","));

        return 0;
    }
}