The Apache Commons CLI library provides an API for parsing command line options passed to programs. It's also able to print help messages detailing the options available for a command line tool.
Apache Commons CLI库提供了一批API,用来解析以命令行形式传递给程序的参数。同事,也可以用来打印 如何使用这些参数的help信息。
Apache Commons CLI支持的类型有:
- 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)
一个典型的Apache Commons CLI使用方式如下:
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 <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