GPattern pattern matching

Author:junwen 2019-10-2

Qq:294712221

https://github.com/junwen12221/GPattern

中文介绍

https://github.com/junwen12221/GPattern/blob/master/README-CN.md

complementary https://github.com/JoanZapata/string-format

Quick Start

GPatternBuilder patternBuilder = new GPatternBuilder(0);
Int id = patternBuilder.addRule("SELECT id FROM {table} LIMIT 1;");
GPattern gPattern = patternBuilder.createGroupPattern();
GPatternMatcher matcher = gPattern.matcher("SELECT id FROM travelrecord LIMIT 1;");
Assert.assertTrue(matcher.acceptAll());
Assert.assertEquals(0, id);
Assert.assertEquals("travelrecord", gPattern.toContextMap(matcher).get("table"));

lexical analyzer

aims

UTF8 or ASCII byte count components into multiple lexical units according to the following lexical rules

Space

Space-separated lexical unit

 
\t
\f

Comments

Comments are used to add hints, notes, suggestions, warnings, etc. to the source code. These information are ignored in lexical analysis.

Single line comment (single-line comment)

-- Single line comment
// single line comment
#单行注

Multi-line comment (multiple-line comment)

/* Multi-line comments */
/*

Multi-line comment

*/

lexical unit (Token)

Direct quantity

Direct quantities only support ASCII characters

String Direct Quantity

'id'
"id"

escaped string direct quantity

`id`

Identifier

Identifies the sequence of ASCII direct quantifiers in the pattern.

Single character

ASCII characters separated by spaces and length 1

Character sequence

A space-separated sequence of characters containing letters or numbers or underscores ("_") or dollar signs ("$") (length greater than 1)

Uppercase

By default case is ignored, the size is converted to lowercase, you can turn off this feature

pattern matching

Name capture

Capture multiple or one lexical units, save them at the beginning and end of the byte array, and get their range in the byte array by name

{name}, where name must be an ASCII character

The byte array to be matched allows UTF8 characters

A lexical unit capture

mode:

SELECT id FROM {table} LIMIT 1;

Pending string

SELECT id FROM travelrecord LIMIT 1;

You can get travelrecord according to 'table'

Multiple lexical unit capture

Pending string

SELECT id FROM travelrecord , travelrecord2 LIMIT 1;

Can be obtained by 'table'

Travelrecord ,travelrecord2

Direct quantity priority matching

mode:

SELECT id FROM {table} LIMIT 1;// Mode 1
SELECT id FROM {table} LIMIT {n};// mode 2

Pending string

SELECT id FROM travelrecord LIMIT 1;

Mode 1 match

pattern ID

GPatternBuilder patternBuilder = new GPatternBuilder(0);
int id = patternBuilder.addRule("{any} FROM travelrecord {any2}");//the mode corresponds to an id
GPattern gPattern = patternBuilder.createGroupPattern();
GPatternMatcher matcher = gPattern.matcher("SELECT id FROM travelrecord LIMIT 1");
Assert.assertTrue(matcher.acceptAll());
Assert.assertEquals(0, id);
Assert.assertEquals(id, matcher.id());// After the pattern matching is successful, the id corresponding to the mode can be obtained according to the matcher.
Map<String, String> map = gPattern.toContextMap(matcher);
Assert.assertEquals("SELECT id", map.get("any"));
Assert.assertEquals("LIMIT 1", map.get("any2"));

License

GPLv3

(http://creativecommons.org/licenses/by-sa/4.0/)

This work is licensed under a [Creative Commons Attribution-ShareAlike 4.0 International License] (http://creativecommons.org/licenses/by-sa/4.0/).

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