java 命令类_Java命令行参数类 Commons CLI使用

一、介绍

Commons CLI库是apache的一个子项目，比较起来，其使用方法相对规范。  http://commons.apache.org/proper/commons-cli/

Commons CLI supports different types of options:

POSIX like options (ie. tar -zxvf foo.tar.gz)

GNU like long options (ie. du --human-readable --max-depth=1)

Java like properties (ie. java -Djava.awt.headless=true -Djava.net.useSystemProxies=true Foo)

Short options with value attached (ie. gcc -O2 foo.c)

long options with single hyphen (ie. ant -projecthelp)

A typical help message displayed by Commons CLI looks like this:

usage: ls

-A,--almost-all          do not list implied . and ..

-a,--all                 do not hide entries starting with .

-B,--ignore-backups      do not list implied entried ending with ~

-b,--escape              print octal escapes for nongraphic characters

--block-size    use SIZE-byte blocks

-c                       with -lt: sort by, and show, ctime (time of last

modification of file status information) with

-l:show ctime and sort by name otherwise: sort

by ctime

-C                       list entries by columns

二、例子

package Test;

import org.apache.commons.cli.BasicParser;

import org.apache.commons.cli.CommandLine;

import org.apache.commons.cli.CommandLineParser;

import org.apache.commons.cli.GnuParser;

import org.apache.commons.cli.HelpFormatter;

import org.apache.commons.cli.Option;

import org.apache.commons.cli.Options;

import org.apache.commons.cli.ParseException;

import org.apache.commons.cli.PosixParser;

public class CLITest {

public static void main(String[] args) throws ParseException {

Options options = new Options();

//短选项，长选项，选项后是否有参数，描述

Option option = new Option("n", "name", true, "the name of this agent");

option.setRequired(true);//必须设置

options.addOption(option);

option = new Option("f", "conf-file", true,

"specify a config file (required if -z missing)");

option.setRequired(false);

options.addOption(option);

option = new Option("h", "help", false, "display help text");

options.addOption(option);

//CommandLineParser parser = new PosixParser();//Posix风格

CommandLineParser parser = new GnuParser();//gun风格

CommandLine commandLine = parser.parse(options, args);

//判断

if (commandLine.hasOption('h')) {

//格式化输出

new HelpFormatter().printHelp("flume-ng agent", options, true);

return;

}

if (commandLine.hasOption('f')) {

//获取参数

String file = commandLine.getOptionValue('f');

}

}

}