de.weltraumschaf.commons.shell

Class DefaultParser

java.lang.Object

de.weltraumschaf.commons.shell.DefaultParser

All Implemented Interfaces:

Parser

class DefaultParser
extends Object
implements Parser

Default parses implementation.

Parsed grammar:

 imputline  = command { argument } .
 command    = keyword [ keyword ] .
 keyword    = character { character } .
 argument   = literal | number | string | boolean.
 literal    = alphanum { alphanum } .
 number     = integer | float .
 integer    = [ sign ] digit { digit } .
 float      = [ sign ] digit { digit } '.' digit { digit } [ exponent ] .
 exponent   = ( 'e' | 'E' ) [ sign ] digit { digit } .
 boolean    = 'true' | 'false' .
 string     = '\'' alphanum { whitespace | alphanum } '\''
              | '"' alphanum { whitespace | alphanum } '"' .
 alphanum   = character
            | digit .
 character  = 'a' .. 'z'
            | 'A' .. 'Z' .
 digit      = '0' .. '9' .
 sign       = '-' | '+' .
 whitespace = ' ' .
 

Since:

1.0.0

Author:

Sven Strittmatter <weltraumschaf@googlemail.com>

Field Summary

Fields

Modifier and Type	Field and Description
private LiteralCommandMap	commandMap Map used to determine command keywords.
private Scanner	scanner Tokenize the input line.
private CommandVerifier	verifier Verifies the parsed commands.

Constructor Summary

Constructors

Constructor and Description
DefaultParser(Scanner scanner, CommandVerifier verifier, LiteralCommandMap commandMap) Dedicated constructor.

Method Summary

Modifier and Type	Method and Description
ShellCommand	parse(String input) Parses given input line.

Methods inherited from class java.lang.Object

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

Field Detail

scanner

private final Scanner scanner

Tokenize the input line.

verifier

private final CommandVerifier verifier

Verifies the parsed commands.

commandMap

private final LiteralCommandMap commandMap

Map used to determine command keywords.

Constructor Detail

DefaultParser

public DefaultParser(Scanner scanner,
                     CommandVerifier verifier,
                     LiteralCommandMap commandMap)

Dedicated constructor.

Parameters:

scanner - must not be null

verifier - must not be null

commandMap - must not be null

Method Detail

parse

public ShellCommand parse(String input)
                   throws SyntaxException

Parses given input line. Parses given input line.

Specified by:

parse in interface Parser

Parameters:

input - line to parse

Returns:

recognized shell command

Throws:

SyntaxException - if, the parsed line has syntax errors