com.persistit

Class CLI

java.lang.Object

com.persistit.CLI

public class CLI
extends Object

Handle commands delivered interactively as command strings. For example, the following loads a Persistit database located in directory /var/lib/data, selects a volume named xyz, and displays page 42 of that volume:

 load datapath=/var/lib/data
 select volume=xyz
 view page=42
 

CLI operates in one of two modes: "live" and "standalone".

In live mode you use one of several access methods to invoke commands to be processed within an actively running server process that has initialized Persistit. Access methods include the AdminUI utility, the Persistit management MBean, a simple network server that can receive command lines from an external tool, or via an application program using the Management interface.

In stand-alone mode you specify through the open command a path on which to find Persistit database files; the open command creates a read-only version Persistit instance capable of performing read-only operations such as save, backup or icheck on the data found in those files.

CLI can set up an extremely simple network server that works with telnet, curl or the simple client built into the main(String[]) method of this class. The advantage is that you can then issue commands interactively from a simple network client using the full facilities of the shell, including piping the output to tools such as grep and more.

To run the CLI in standalone mode, simply execute

 java -cp persisit.jar com.persistit.Persistit cliport=9999
 

or

 java -cp persisit.jar com.persistit.Persistit script=pathname
 

where persistit.jar contains the Persistit library. The first option specifies a port on which CLI will listen for commands. (Use a port number larger than 1024 to avoid permissions problems.) The second option executes commands from a text file in batch mode.

The following *nix client script works with the network server facility:

   #!/bin/sh
   java -cp persistit.jar com.persistit.CLI 9999 $*
 

(Substitute the port number assigned to the cliport parameter above.)

With this script you can then enter command such as this at the shell:

 pcli init datapath=/var/lib/data
 pcli select volume=xyz
 pcli view page=42
 

Commands are defined below in methods annotated with @Cmd having parameters annotated with @Arg. The format of the argument annotation is specified in ArgParser. Enter the command 'help' to see a readable list of commands and their arguments.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	CLI.Arg Annotation for parameters of command methods
static interface	CLI.Cmd Annotation for methods that implement commands

Constructor Summary

Constructors

Constructor and Description
CLI(Persistit persistit)
CLI(Persistit persistit, BufferedReader reader, PrintWriter writer)
CLI(Persistit persistit, int port)

Method Summary

Modifier and Type	Method and Description
static void	main(String[] args) Simple client for CLI server.
static List<String>	pieces(String commandLine) Parse a command line string consisting of a command followed by flags and name=value parameters, all separate by spaces.
static void	registerCommands(Class<?> clazz) Registers command methods provided by the supplied Class.
static void	runScript(Persistit persistit, BufferedReader reader, PrintWriter writer) Invoke lines read from the supplied BufferedReader as CLI commands and write any generated output to the supplied PrintWriter.

Methods inherited from class java.lang.Object

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

Constructor Detail

CLI

public CLI(Persistit persistit)

CLI

public CLI(Persistit persistit,
           int port)
    throws IOException

Throws:

IOException

CLI

public CLI(Persistit persistit,
           BufferedReader reader,
           PrintWriter writer)

Method Detail

registerCommands

public static void registerCommands(Class<?> clazz)

Registers command methods provided by the supplied Class. To be registered as a CLI command, a method must be identified by a @Cmd annotation, and its arguments must be defined with @Arg annotations. This method allows applications to extend the CLI.

Parameters:

clazz -

main

public static void main(String[] args)
                 throws Exception

Simple client for CLI server. Run the command

 
 java -cp classpath com.persistit.CLI port command arg arg arg ...
 
 

to execute a CLI command on the CLI server, e.g.,

 
 java -cp persistit.jar com.persistit.CLI 9999 select volume=akiban_data
 
 

To execute the select command on a server on port 9999.

Parameters:

args -

Throws:

Exception

runScript

public static void runScript(Persistit persistit,
                             BufferedReader reader,
                             PrintWriter writer)
                      throws Exception

Invoke lines read from the supplied BufferedReader as CLI commands and write any generated output to the supplied PrintWriter.

Parameters:

persistit -

reader -

writer -

Throws:

Exception

pieces

public static List<String> pieces(String commandLine)

Parse a command line string consisting of a command followed by flags and name=value parameters, all separate by spaces. Argument values containing spaces can be quoted by a leading backslash.

Parameters:

commandLine -

Returns:

List of String values, one per command name or argument token.