import net.sourceforge.argparse4j.internal.HelpScreenException; //导入依赖的package包/类
public int parseArguments(final String[] args) {
    try {
        this.ns = this.parser.parseArgs(args);
    }
    catch (ArgumentParserException e) {
        this.parser.handleError(e);
        if (e instanceof HelpScreenException) {
            return 1;
        }
        if (e instanceof UnsupportedTargetException) {
            printTargets();
        }
        return -1;
    }

    this.command = Command.getByName(ns.getString("command"));
    this.assignTarget(ns);
    this.assignGlobalOptions(ns);
    this.assignCommandOptions(ns);

    if (this.debug > 1) {
        System.out.println(ns);
        this.printArgs();
    }
    return 0;
}
 

import net.sourceforge.argparse4j.internal.HelpScreenException; //导入依赖的package包/类
/**
 * @throws HelpScreenException help text printed, nameSpace is not updated!
 * @throws UserErrorException
 */
private void parseArgs() throws HelpScreenException, UserErrorException {
	
	try {
		nameSpace = parser.parseArgs(args);		
		
	} catch (ArgumentParserException e) {
		if (e instanceof HelpScreenException) {
			throw (HelpScreenException)e;
		} else {
			throw new UserErrorException(e.getMessage());
		}
	}
}
 

import net.sourceforge.argparse4j.internal.HelpScreenException; //导入依赖的package包/类
public static void main(final String[] args) {
    final ArgumentParser parser = ArgumentParsers.newArgumentParser(CLTool.class.getSimpleName())
        .description("Tool to pseudonymize certain DNS packets packets in PCAP or PCAPNG files.")
        .version("0.0.1");

    final ArgumentGroup requiredGroup = parser.addArgumentGroup("required arguments");

    requiredGroup.addArgument("-i", "--infile")
        .required(true)
        .metavar("infile")
        .type(String.class)
        .action(new FileCheckAction())
        .help("the input file to process (either PCAP or PCAPNG)");
    requiredGroup.addArgument("-o", "--outfile")
        .required(true)
        .metavar("outfile")
        .type(String.class)
        .help("the output file to create and write to");
    parser.addArgument("-v", "--version")
        .action(Arguments.version())
        .help("show the program version");
    parser.addArgument("-4", "--pseudo4")
        .nargs(2)
        .metavar("key", "mask")
        .action(new Pseudo4CheckAction())
        .help("pseudonymize the masked part of IPv4 addresses using FPE, with given key");
    parser.addArgument("-6", "--pseudo6")
        .nargs(2)
        .metavar("key", "mask")
        .action(new Pseudo6CheckAction())
        .help("pseudonymize the masked part of IPv6 addresses using FPE, with given key");
    parser.addArgument("-c", "--checksum")
        .nargs(1)
        .metavar("[ipv4,udp,icmp] or all")
        .action(new ChecksumCheckAction())
        .help("recalculate checksums of given protocols (given as comma separated list or 'all')");
    parser.addArgument("-m", "--multithread")
        .metavar("numthreads")
        .type(Integer.class)
        .choices(Arguments.range(1, 127)) // TODO: range as [1, maxDetectedCores]?
        .help("use multithreading with specified number of threads, in range of [1, 127]");

    try {
        final Namespace cmdResult = parser.parseArgs(args);
        runTool(cmdResult);
    }
    catch (final HelpScreenException hse) {
        // this is the normal behaviour, throwing exception when asking for help
        // in this case, do nothing
    }
    catch (final ArgumentParserException ape) {
        System.err.println(parser.formatUsage() + CLTool.class.getSimpleName() + ": error: " + ape.getMessage());
    }
}