de.unkrig.commons.text.parser
Class AbstractParser<TT extends java.lang.Enum<TT>>

java.lang.Object
  de.unkrig.commons.text.parser.AbstractParser<TT>

Type Parameters:

TT - The enumerator representing the scanner's token types

Direct Known Subclasses:

JsonParser, Parser

public class AbstractParser<TT extends java.lang.Enum<TT>>
extends java.lang.Object

The base class for implementing parsers. Typically, you would declare methods named 'parse...()' which invoke each other and the 'peek...()', 'read...()' and 'peekRead...()' methods to parse a document.

Field Summary

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

scanner The source of tokens that are processed by this parser.

Constructor Summary

AbstractParser(ProducerWhichThrows<AbstractScanner.Token<TT>,ScanException> scanner)

Method Summary

void	eoi()
AbstractScanner.Token<TT>	peek() Checks the next token, but does not consume it.
int	peek(java.lang.Object... tokenTypeOrText) Checks the next token, but does not consume it.
boolean	peek(java.lang.String text) Checks the next token, but does not consume it.
java.lang.String	peek(TT tokenType) Checks the next token, but does not consume it.
int	peekRead(java.lang.String... texts) Checks the next token and consumes it if its text equals any of texts.
boolean	peekRead(java.lang.String text) Checks the next token and consumes it if its text equals text.
AbstractScanner.Token<TT>	peekRead(TT... tokenTypes) Checks the next token and consumes it if its type is one of the tokenTypes.
java.lang.String	peekRead(TT tokenType) Checks the next token and consumes it if its type is tokenType.
<T extends java.lang.Enum<T>> T	peekReadEnum(T... values) Checks the next token and consumes it if its text equals the return value of toString() of one of the values.
AbstractScanner.Token<TT>	read() Consumes the next token.
int	read(java.lang.Object... tokenTypeOrText) Consumes the next token.
void	read(java.lang.String text) Consumes the next token.
java.lang.String	read(TT tokenType) Consumes the next token.

Methods inherited from class java.lang.Object

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

Field Detail

scanner

protected final ProducerWhichThrows<AbstractScanner.Token<TT extends java.lang.Enum<TT>>,ScanException> scanner

The source of tokens that are processed by this parser.

Constructor Detail

AbstractParser

public AbstractParser(ProducerWhichThrows<AbstractScanner.Token<TT>,ScanException> scanner)

Parameters:

scanner - Its toString() method returns a human-readable indication of the scanner location

Method Detail

peek

@Nullable
public AbstractScanner.Token<TT> peek()
                                                          throws ParseException

Checks the next token, but does not consume it.

Returns:

The next token, or null if the scanner is at end-of-input

Throws:

ParseException

peek

@Nullable
public java.lang.String peek(TT tokenType)
                      throws ParseException

Checks the next token, but does not consume it.

Returns:

The next token's text, or null if the next token's type is not tokenType, or if the scanner is at end-of-input

Throws:

ParseException

peek

public boolean peek(java.lang.String text)
             throws ParseException

Checks the next token, but does not consume it.

Returns:

Whether the scanner is not at end-of-input and the next token's text equals text

Throws:

ParseException

peek

public int peek(java.lang.Object... tokenTypeOrText)
         throws ParseException

Checks the next token, but does not consume it.

Returns:

The index of the first of tokenTypeOrText which equals either the next token's type or text, or -1

Throws:

ParseException

peekRead

@Nullable
public java.lang.String peekRead(TT tokenType)
                          throws ParseException

Checks the next token and consumes it if its type is tokenType.

Returns:

The text of the next token, or null if the next token's type is not tokenType, or if the scanner is at end-of-input

Throws:

ParseException

peekRead

public boolean peekRead(java.lang.String text)
                 throws ParseException

Checks the next token and consumes it if its text equals text.

Returns:

Whether the scanner is not at end-of-input and the next token's text equals text

Throws:

ParseException

peekRead

public int peekRead(java.lang.String... texts)
             throws ParseException

Checks the next token and consumes it if its text equals any of texts.

Returns:

The index of the first of texts which equals the next token's text, or -1

Throws:

ParseException

peekReadEnum

@Nullable
public <T extends java.lang.Enum<T>> T peekReadEnum(T... values)
                                         throws ParseException

Checks the next token and consumes it if its text equals the return value of toString() of one of the values.

Returns:

The matched value, or null if none matches

Throws:

ParseException

peekRead

@Nullable
public AbstractScanner.Token<TT> peekRead(TT... tokenTypes)
                                                              throws ParseException

Checks the next token and consumes it if its type is one of the tokenTypes.

Returns:

The matched token, or null iff none matches

Throws:

ParseException

read

public AbstractScanner.Token<TT> read()
                                                          throws ParseException

Consumes the next token.

Returns:

The next token

Throws:

ParseException - The scanner is at end-of-input

read

public java.lang.String read(TT tokenType)
                      throws ParseException

Consumes the next token.

Returns:

The next token's text

Throws:

ParseException - The next token's type is not tokenType

ParseException - The scanner is at end-of-input

read

public void read(java.lang.String text)
          throws ParseException

Consumes the next token.

Throws:

ParseException - The next token's text does not equal text

ParseException - The scanner is at end-of-input

See Also:

eoi()

read

public int read(java.lang.Object... tokenTypeOrText)
         throws ParseException

Consumes the next token.

Returns:

The index of the first of tokenTypeOrText which equals either the next token's type or text

Throws:

ParseException - Neither the next token's type nor its text equals any of tokenTypeOrText

ParseException - The scanner is at end-of-input

eoi

public void eoi()
         throws ParseException

Throws:

ParseException - Iff the scanner is not at end-of-input