Spark shell command lines

问题:

I am new to Spark and trying to figure out how can I use the Spark shell.

Looked into Spark's site documentation and it doesn't show how to create directories or how to see all my files in spark shell. If anyone could help me I would appreciate it.

回答1:

In this context you can assume that Spark shell is just a normal Scala REPL so the same rules apply. You can get a list of the available commands using :help.

Welcome to       ____              __      / __/__  ___ _____/ /__     _\ \/ _ \/ _ `/ __/  '_/    /___/ .__/\_,_/_/ /_/\_\   version 2.3.0       /_/  Using Scala version 2.11.8 (OpenJDK 64-Bit Server VM, Java 1.8.0_151) Type in expressions to have them evaluated. Type :help for more information.  scala> :help All commands can be abbreviated, e.g., :he instead of :help. :edit <id>|<line>        edit history :help [command]          print this summary or command-specific help :history [num]           show the history (optional num is commands to show) :h? <string>             search the history :imports [name name ...] show import history, identifying sources of names :implicits [-v]          show the implicits in scope :javap <path|class>      disassemble a file or class name :line <id>|<line>        place line(s) at the end of history :load <path>             interpret lines in a file :paste [-raw] [path]     enter paste mode or paste a file :power                   enable power user mode :quit                    exit the interpreter :replay [options]        reset the repl and replay all previous commands :require <path>          add a jar to the classpath :reset [options]         reset the repl to its initial state, forgetting all session entries :save <path>             save replayable session to a file :sh <command line>       run a shell command (result is implicitly => List[String]) :settings <options>      update compiler options, if possible; see reset :silent                  disable/enable automatic printing of results :type [-v] <expr>        display the type of an expression without evaluating it :kind [-v] <expr>        display the kind of expression's type :warnings                show the suppressed warnings from the most recent line which had any 

As you can see above you can invoke shell commands using :sh. For example:

scala> :sh mkdir foobar res0: scala.tools.nsc.interpreter.ProcessResult = `mkdir foobar` (0 lines, exit 0)  scala> :sh touch foobar/foo res1: scala.tools.nsc.interpreter.ProcessResult = `touch foobar/foo` (0 lines, exit 0)  scala> :sh touch foobar/bar res2: scala.tools.nsc.interpreter.ProcessResult = `touch foobar/bar` (0 lines, exit 0)  scala> :sh ls foobar res3: scala.tools.nsc.interpreter.ProcessResult = `ls foobar` (2 lines, exit 0)  scala> res3.line foreach println line   lines  scala> res3.lines foreach println bar foo 

回答2:

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:q or :quit command is used to exit from scala ripple.

文章来源: Spark shell command lines