alluxio.cli

Class CommandUtils

java.lang.Object

alluxio.cli.CommandUtils

@ThreadSafe
public final class CommandUtils
extends Object

Class for convenience methods used by instances of Command.

Method Summary

Modifier and Type	Method and Description
static void	checkNumOfArgsEquals(Command cmd, org.apache.commons.cli.CommandLine cl, int n) Checks the number of non-option arguments equals n for command.
static void	checkNumOfArgsNoLessThan(Command cmd, org.apache.commons.cli.CommandLine cl, int n) Checks the number of non-option arguments is no less than n for command.
static void	checkNumOfArgsNoMoreThan(Command cmd, org.apache.commons.cli.CommandLine cl, int n) Checks the number of non-option arguments is no more than n for command.
static Map<String,Command>	loadCommands(String pkgName, Class[] classArgs, Object[] objectArgs) Get instances of all subclasses of Command in a sub-package called "command" the given package.
static Set<String>	readNodeList(String confDir, String fileName) Reads a list of nodes from given file name ignoring comments and empty lines.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

loadCommands

public static Map<String,Command> loadCommands(String pkgName,
                                               Class[] classArgs,
                                               Object[] objectArgs)

Get instances of all subclasses of Command in a sub-package called "command" the given package.

Parameters:

pkgName - package prefix to look in

classArgs - type of args to instantiate the class

objectArgs - args to instantiate the class

Returns:

a mapping from command name to command instance

checkNumOfArgsEquals

public static void checkNumOfArgsEquals(Command cmd,
                                        org.apache.commons.cli.CommandLine cl,
                                        int n)
                                 throws InvalidArgumentException

Checks the number of non-option arguments equals n for command.

Parameters:

cmd - command instance

cl - parsed commandline arguments

n - an integer

Throws:

InvalidArgumentException - if the number does not equal n

checkNumOfArgsNoLessThan

public static void checkNumOfArgsNoLessThan(Command cmd,
                                            org.apache.commons.cli.CommandLine cl,
                                            int n)
                                     throws InvalidArgumentException

Checks the number of non-option arguments is no less than n for command.

Parameters:

cmd - command instance

cl - parsed commandline arguments

n - an integer

Throws:

InvalidArgumentException - if the number is smaller than n

checkNumOfArgsNoMoreThan

public static void checkNumOfArgsNoMoreThan(Command cmd,
                                            org.apache.commons.cli.CommandLine cl,
                                            int n)
                                     throws InvalidArgumentException

Checks the number of non-option arguments is no more than n for command.

Parameters:

cmd - command instance

cl - parsed commandline arguments

n - an integer

Throws:

InvalidArgumentException - if the number is greater than n

readNodeList

@Nullable
public static Set<String> readNodeList(String confDir,
                                                 String fileName)

Reads a list of nodes from given file name ignoring comments and empty lines. Can be used to read conf/workers or conf/masters.

Parameters:

confDir - directory that holds the configuration

fileName - name of a file that contains the list of the nodes

Returns:

list of the node names, null when file fails to read