io.debezium.relational.ddl

Class DataTypeGrammarParser

java.lang.Object

io.debezium.relational.ddl.DataTypeGrammarParser

@Immutable
public class DataTypeGrammarParser
extends Object

A parser for data type grammars that produces one DataTypeGrammarParser.DataTypePattern for a grammar, where the DataTypeGrammarParser.DataTypePattern can be used when parsing content containing data types adhering to the grammar(s).

The grammar using the following rules:

• Uppercase keyword or word tokens are considered literals that much be matched case-insensitively but completely.
• Lowercase keyword or word tokens are considered logical names of a variable and will match and single token.
• Optional tokens are delimited by '[' and ']' characters.
• The type length, L (or mantissa, M) is specified with '(L)' or '(M)', or if coupled with a scale, S, with '(L,S)' or '(M,D)'. In these cases, the length will match any positive long, and scale will match any integer value. When the length or scale are represented with integers, they will match only those values.
• The type may have a length of ..., in which case the parser will allow (but not capture) a list of values.
• The literal '{n}' signals that the grammar can allow array dimensions at this point.

For example, the following are valid data type grammars:

• BIT
• BIT(3) will match when the length is exactly 3 and will not match BIT(2).
• DECIMAL(L[,S]) will match DECIMAL(5) and DECIMAL (10,3)
• INTEGER{n} will match INTEGER[3], which is an array of integers.
• ENUM(...) will match ENUM(a,b,c,d) and ENUM(a).

Author:

Randall Hauch

See Also:

DataTypeParser

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected static class	DataTypeGrammarParser.AndPattern
protected static class	DataTypeGrammarParser.ArrayDimensionsPattern
static class	DataTypeGrammarParser.DataTypePattern
protected static class	DataTypeGrammarParser.LengthPattern
protected static class	DataTypeGrammarParser.ListPattern
protected static class	DataTypeGrammarParser.LiteralLengthPattern
protected static class	DataTypeGrammarParser.LiteralPattern
protected static class	DataTypeGrammarParser.LiteralScalePattern
protected static class	DataTypeGrammarParser.OptionalPattern
protected static class	DataTypeGrammarParser.OrPattern
protected static interface	DataTypeGrammarParser.Pattern
protected static class	DataTypeGrammarParser.ScalePattern
protected static class	DataTypeGrammarParser.VariablePattern

Field Summary

Fields

Modifier and Type	Field and Description
private DdlTokenizer	tokenizer

Constructor Summary

Constructors

Constructor and Description
DataTypeGrammarParser() Create a new instance of the data type grammar parser.

Method Summary

Modifier and Type	Method and Description
DataTypeGrammarParser.DataTypePattern	parse(int jdbcType, String dataTypeDefn) Parse the supplied grammar for a data type.
protected DataTypeGrammarParser.Pattern	parseArrayDimensions(TokenStream stream)
protected DataTypeGrammarParser.Pattern	parseLength(TokenStream stream)
protected DataTypeGrammarParser.Pattern	parseLengthLiteral(TokenStream stream)
protected DataTypeGrammarParser.Pattern	parseMultiple(TokenStream stream)
protected DataTypeGrammarParser.Pattern	parseOptional(TokenStream stream, Function<TokenStream,DataTypeGrammarParser.Pattern> inside)
protected DataTypeGrammarParser.Pattern	parsePattern(TokenStream stream)
protected DataTypeGrammarParser.Pattern	parseScale(TokenStream stream)
protected DataTypeGrammarParser.Pattern	parseScaleLiteral(TokenStream stream)

Methods inherited from class java.lang.Object

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

Field Detail

tokenizer

private final DdlTokenizer tokenizer

Constructor Detail

DataTypeGrammarParser

public DataTypeGrammarParser()

Create a new instance of the data type grammar parser.

Method Detail

parse

public DataTypeGrammarParser.DataTypePattern parse(int jdbcType,
                                                   String dataTypeDefn)
                                            throws ParsingException

Parse the supplied grammar for a data type.

Parameters:

jdbcType - the JDBC data type

dataTypeDefn - the data type grammar

Returns:

the data type pattern that can be used for pattern matching the data type; never null

Throws:

ParsingException - if the grammar cannot be parsed correctly

parseMultiple

protected DataTypeGrammarParser.Pattern parseMultiple(TokenStream stream)
                                               throws ParsingException

Throws:

ParsingException

parsePattern

protected DataTypeGrammarParser.Pattern parsePattern(TokenStream stream)
                                              throws ParsingException

Throws:

ParsingException

parseOptional

protected DataTypeGrammarParser.Pattern parseOptional(TokenStream stream,
                                                      Function<TokenStream,DataTypeGrammarParser.Pattern> inside)
                                               throws ParsingException

Throws:

ParsingException

parseArrayDimensions

protected DataTypeGrammarParser.Pattern parseArrayDimensions(TokenStream stream)
                                                      throws ParsingException

Throws:

ParsingException

parseLength

protected DataTypeGrammarParser.Pattern parseLength(TokenStream stream)
                                             throws ParsingException

Throws:

ParsingException

parseScale

protected DataTypeGrammarParser.Pattern parseScale(TokenStream stream)
                                            throws ParsingException

Throws:

ParsingException

parseLengthLiteral

protected DataTypeGrammarParser.Pattern parseLengthLiteral(TokenStream stream)
                                                    throws ParsingException

Throws:

ParsingException

parseScaleLiteral

protected DataTypeGrammarParser.Pattern parseScaleLiteral(TokenStream stream)
                                                   throws ParsingException

Throws:

ParsingException