de.unkrig.commons.text.scanner

Class StatelessScanner<TT extends Enum<TT>>

java.lang.Object

de.unkrig.commons.text.scanner.AbstractScanner<TT>

de.unkrig.commons.text.scanner.StatelessScanner<TT>

Type Parameters:

TT - Enumerates the scanner-specific token types

All Implemented Interfaces:

ProducerWhichThrows<AbstractScanner.Token<TT>,ScanException>, StringScanner<TT>

public class StatelessScanner<TT extends Enum<TT>>
extends AbstractScanner<TT>

A scanner that produces AbstractScanner.Tokens. Before produce() is called, the scanner must be configured by invoking its addRule(String, Enum) methods. These define how character sequences are converted into AbstractScanner.Tokens.

For an example usage, see the source code of Scanner

Nested Class Summary

Nested classes/interfaces inherited from class de.unkrig.commons.text.scanner.AbstractScanner

AbstractScanner.Token<TT extends Enum<TT>>

Field Summary

Fields inherited from class de.unkrig.commons.text.scanner.AbstractScanner

cs, offset, previousTokenOffset

Constructor Summary

Constructors

Constructor and Description
StatelessScanner()

Method Summary

Modifier and Type	Method and Description
void	addRule(String regex, TT tokenType) Adds a rule that produces the given tokenType if the next characters of the input match the given regex.
AbstractScanner.Token<TT>	produce() Before StringScanner.setInput(CharSequence) is called, this method returns null.

Methods inherited from class de.unkrig.commons.text.scanner.AbstractScanner

getOffset, getPreviousTokenOffset, setInput, suppress, suppress, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

StatelessScanner

public StatelessScanner()

Method Detail

addRule

public void addRule(String regex,
                    TT tokenType)

Adds a rule that produces the given tokenType if the next characters of the input match the given regex.

produce

@Nullable
public AbstractScanner.Token<TT> produce()
                                             throws ScanException

Description copied from interface: StringScanner

Before StringScanner.setInput(CharSequence) is called, this method returns null. After StringScanner.setInput(CharSequence) was called, this method breaks the input char character sequence up into tokens and returns them one by one. When the input char sequence is exhausted, null is returned until StringScanner.setInput(CharSequence) is called again.

Returns:

null iff the input string is exhausted

Throws:

ScanException