public class GenericOptionsParser extends Object
GenericOptionsParser
is a utility to parse command line
arguments generic to the Hadoop framework.
GenericOptionsParser
recognizes several standarad command
line arguments, enabling applications to easily specify a namenode, a
jobtracker, additional configuration resources etc.
The supported generic options are:
-conf <configuration file> specify a configuration file -D <property=value> use value for given property -fs <local|namenode:port> specify a namenode -jt <local|jobtracker:port> specify a job tracker -files <comma separated list of files> specify comma separated files to be copied to the map reduce cluster -libjars <comma separated list of jars> specify comma separated jar files to include in the classpath. -archives <comma separated list of archives> specify comma separated archives to be unarchived on the compute machines.
The general command line syntax is:
bin/hadoop command [genericOptions] [commandOptions]
Generic command line arguments might modify
Configuration
objects, given to constructors.
The functionality is implemented using Commons CLI.
Examples:
$ bin/hadoop dfs -fs darwin:8020 -ls /data list /data directory in dfs with namenode darwin:8020 $ bin/hadoop dfs -D fs.default.name=darwin:8020 -ls /data list /data directory in dfs with namenode darwin:8020 $ bin/hadoop dfs -conf hadoop-site.xml -ls /data list /data directory in dfs with conf specified in hadoop-site.xml $ bin/hadoop job -D mapred.job.tracker=darwin:50020 -submit job.xml submit a job to job tracker darwin:50020 $ bin/hadoop job -jt darwin:50020 -submit job.xml submit a job to job tracker darwin:50020 $ bin/hadoop job -jt local -submit job.xml submit a job to local runner $ bin/hadoop jar -libjars testlib.jar -archives test.tgz -files file.txt inputjar args job submission with libjars, files and archives
Tool
,
ToolRunner
构造器和说明 |
---|
GenericOptionsParser(Configuration conf,
org.apache.commons.cli.Options options,
String[] args)
Create a
GenericOptionsParser to parse given options as well
as generic Hadoop options. |
GenericOptionsParser(Configuration conf,
String[] args)
Create a GenericOptionsParser
|
GenericOptionsParser(org.apache.commons.cli.Options opts,
String[] args)
Create an options parser with the given options to parse the args.
|
GenericOptionsParser(String[] args)
Create an options parser to parse the args.
|
限定符和类型 | 方法和说明 |
---|---|
org.apache.commons.cli.CommandLine |
getCommandLine()
Returns the commons-cli
CommandLine object
to process the parsed arguments. |
Configuration |
getConfiguration()
Get the modified configuration
|
static URL[] |
getLibJars(Configuration conf)
If libjars are set in the conf, parse the libjars.
|
String[] |
getRemainingArgs()
Returns an array of Strings containing only application-specific arguments.
|
static void |
printGenericCommandUsage(PrintStream out)
Print the usage message for generic command-line options supported.
|
public GenericOptionsParser(org.apache.commons.cli.Options opts, String[] args) throws IOException
opts
- the optionsargs
- the command line argumentsIOException
public GenericOptionsParser(String[] args) throws IOException
args
- the command line argumentsIOException
public GenericOptionsParser(Configuration conf, String[] args) throws IOException
GenericOptionsParser to parse only the generic Hadoop
arguments.
The array of string arguments other than the generic arguments can be
obtained by getRemainingArgs()
.
- 参数:
conf
- the Configuration
to modify.args
- command-line arguments.
- 抛出:
IOException
-
GenericOptionsParser
public GenericOptionsParser(Configuration conf,
org.apache.commons.cli.Options options,
String[] args)
throws IOException
Create a GenericOptionsParser
to parse given options as well
as generic Hadoop options.
The resulting CommandLine
object can be obtained by
getCommandLine()
.
- 参数:
conf
- the configuration to modifyoptions
- options built by the callerargs
- User-specified arguments
- 抛出:
IOException
-
方法详细资料
-
getRemainingArgs
public String[] getRemainingArgs()
Returns an array of Strings containing only application-specific arguments.
- 返回:
- array of
String
s containing the un-parsed arguments
or empty array if commandLine was not defined.
-
getConfiguration
public Configuration getConfiguration()
Get the modified configuration
- 返回:
- the configuration that has the modified parameters.
-
getCommandLine
public org.apache.commons.cli.CommandLine getCommandLine()
Returns the commons-cli CommandLine
object
to process the parsed arguments.
Note: If the object is created with
GenericOptionsParser(Configuration, String[])
, then returned
object will only contain parsed generic options.
- 返回:
CommandLine
representing list of arguments
parsed against Options descriptor.
-
getLibJars
public static URL[] getLibJars(Configuration conf)
throws IOException
If libjars are set in the conf, parse the libjars.
- 参数:
conf
-
- 返回:
- libjar urls
- 抛出:
IOException
-
printGenericCommandUsage
public static void printGenericCommandUsage(PrintStream out)
Print the usage message for generic command-line options supported.
- 参数:
out
- stream to print the usage message to.
Copyright © 2009 The Apache Software Foundation