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Antlr3 report java.lang.OutOfMemoryError when parse expression

I try to match the string "match 'match content'", meanwhile extract match content that within single quotes. But throws the following exception:
Exception in thread "main" java.lang.OutOfMemoryError: GC overhead limit exceeded
at org.antlr.runtime.Lexer.emit(Lexer.java:160)
at org.antlr.runtime.Lexer.nextToken(Lexer.java:91)
at org.antlr.runtime.BufferedTokenStream.fetch(BufferedTokenStream.java:133)
at org.antlr.runtime.BufferedTokenStream.sync(BufferedTokenStream.java:127)
at org.antlr.runtime.CommonTokenStream.consume(CommonTokenStream.java:70)
at org.antlr.runtime.BaseRecognizer.match(BaseRecognizer.java:106)
I don't known why throws OOM exception and i can not find error define in dot g file.
My dot g file:
grammar Contains;
options {
language=Java;
output=AST;
ASTLabelType=CommonTree;
backtrack=false;
k=3;
}
match
:
KW_MATCH SINGLE_QUOTE ( ~(SINGLE_QUOTE|'\\') | ('\\' .) )+ SINGLE_QUOTE
;
regexp
:
KW_REGEXP SINGLE_QUOTE RegexComponent+ SINGLE_QUOTE
;
range
:
KW_RANGE SINGLE_QUOTE left=(LPAREN | LSQUARE) start=Number COMMA end = Number right=(RPAREN | RSQUARE) SINGLE_QUOTE
;
DOT : '.'; // generated as a part of Number rule
COLON : ':' ;
COMMA : ',' ;
LPAREN : '(' ;
RPAREN : ')' ;
LSQUARE : '[' ;
RSQUARE : ']' ;
LCURLY : '{';
RCURLY : '}';
PLUS : '+';
MINUS : '-';
STAR : '*';
BITWISEOR : '|';
BITWISEXOR : '^';
QUESTION : '?';
DOLLAR : '$';
KW_RANGE : 'RANGE';
KW_REGEXP : 'REGEXP';
KW_MATCH : 'MATCH';
DOUBLE_QUOTE : '\"';
SINGLE_QUOTE : '\'';
fragment
Digit
:
'0'..'9'
;
fragment
Exponent
:
('e' | 'E') ( PLUS|MINUS )? (Digit)+
;
fragment
RegexComponent
: 'a'..'z' | 'A'..'Z' | '0'..'9' | '_'
| PLUS | STAR | QUESTION | MINUS | DOT
| LPAREN | RPAREN | LSQUARE | RSQUARE | LCURLY | RCURLY
| BITWISEXOR | BITWISEOR | DOLLAR | '\u0080'..'\u00FF' | '\u0400'..'\u04FF'
| '\u0600'..'\u06FF' | '\u0900'..'\u09FF' | '\u4E00'..'\u9FFF' | '\u0A00'..'\u0A7F'
;
Number
:
(Digit)+ ( DOT (Digit)* (Exponent)? | Exponent)?
;
WS : (' '|'\r'|'\t'|'\n'|'\u000C')* {$channel=HIDDEN;}
;

You could start by changing:
WS : (' '|'\r'|'\t'|'\n'|'\u000C')* {$channel=HIDDEN;}
;
to:
WS : (' '|'\r'|'\t'|'\n'|'\u000C')+ {$channel=HIDDEN;}
;
Your version matches an empty string, which might produce an infinite amount of tokens (which might throw an OOME).

Antlr 4 TEXT and DIGIT together

I am parsing a SQL like language and I have problems with strings that starts with a number:
SELECT 90userN is parsed to SELECT 90 AS userN
Since I remove the whitespaces, it somehow gets the digits as the name and the string as the alias.
I don't know even where to start.
Grammar:
result_column : '*'
| table_name '.' '*'
| table_name '.' any_name
| expr
any_name : keyword
| IDENTIFIER
| STRING_LITERAL
| '(' any_name ')'
;
expr: literal_value;
literal_value :
NUMERIC_LITERAL
| STRING_LITERAL
| DATE_LITERAL
| IDENTIFIER
| NULL
;
IDENTIFIER :
'"' (~'"' | '""')* '"'
| '`' (~'`' | '``')* '`'
| '[' ~']'* ']'
| [a-zA-Z_] [a-zA-Z_0-9]*;
STRING_LITERAL : '\'' ( ~'\'' | '\'\'' )* '\'' ;
NUMERIC_LITERAL :
DIGIT+ ( '.' DIGIT* )? ( E [-+]? DIGIT+ )?
| '.' DIGIT+ ( E [-+]? DIGIT+ )? ;
DATE_LITERAL: DIGIT DIGIT DIGIT DIGIT '-' DIGIT DIGIT '-' DIGIT DIGIT;

Identifiers in SQL can not start with numbers and that is really clear in the last alternative of your IDENTIFIER rule: [a-zA-Z_] [a-zA-Z_0-9]*;
I think you are already using it, but refer to the SQLite4 grammar example

ANTLR - Join tokens to output

Using ANTLR3, I want to parse Strings such:
name IS NOT empty AND age NOT IN (14, 15)
And for these cases, I want to get the following ASTs:
n0 [label="QUERY"];
n1 [label="AND"];
n1 [label="AND"];
n2 [label="IS NOT"];
n2 [label="IS NOT"];
n3 [label="name"];
n4 [label="empty"];
n5 [label="NOT IN"];
n5 [label="NOT IN"];
n6 [label="age"];
n7 [label="14"];
n8 [label="15"];
n0 -> n1 // "QUERY" -> "AND"
n1 -> n2 // "AND" -> "IS NOT"
n2 -> n3 // "IS NOT" -> "name"
n2 -> n4 // "IS NOT" -> "empty"
n1 -> n5 // "AND" -> "NOT IN"
n5 -> n6 // "NOT IN" -> "age"
n5 -> n7 // "NOT IN" -> "14"
n5 -> n8 // "NOT IN" -> "15"
But my n2 and n5 nodes are appearing like :
n2 [label="IS"];
n5 [label="NOT"];
Ie, just the first word is appearing. How can I join both tokens in just one?
My Grammar is:
query
: expr EOF -> ^(QUERY expr)
;
expr
: logical_expr
;
logical_expr
: equality_expr (logical_op^ equality_expr)*
;
equality_expr
: ID equality_op+ atom -> ^(equality_op ID atom)
| '(' expr ')' -> ^('(' expr)
;
atom
: ID
| id_list
| Int
| Number
| String
| '*'
;
id_list
: '(' ID (',' ID)+ ')' -> ID+
| '(' Number (',' Number)* ')' -> Number+
| '(' String (',' String)* ')' -> String+
;
equality_op
: 'IN'
| 'IS'
| 'NOT'
| 'in'
| 'is'
| 'not'
;
logical_op
: 'AND'
| 'OR'
| 'and'
| 'or'
;
Number
: Int ('.' Digit*)?
;
ID
: ('a'..'z' | 'A'..'Z' | '_' | '.' | '-' | '*' | '/' | ':' | Digit)*
;
String
#after {
setText(getText().substring(1, getText().length()-1).replaceAll("\\\\(.)", "$1"));
}
: '"' (~('"' | '\\') | '\\' ('\\' | '"'))* '"'
| '\'' (~('\'' | '\\') | '\\' ('\\' | '\''))* '\''
;
Comment
: '//' ~('\r' | '\n')* {skip();}
| '/*' .* '*/' {skip();}
;
Space
: (' ' | '\t' | '\r' | '\n' | '\u000C') {skip();}
;
fragment Int
: '1'..'9' Digit*
| '0'
;
fragment Digit
: '0'..'9'
;
indexes
: ('[' expr ']')+ -> ^(INDEXES expr+)
;

Do something like this instead (check the inline comments I added):
tokens {
IS_NOT; // added
NOT_IN; // added
QUERY;
INDEXES;
}
query
: expr EOF -> ^(QUERY expr)
;
expr
: logical_expr
;
logical_expr
: equality_expr (logical_op^ equality_expr)*
;
equality_expr
: ID equality_op atom -> ^(equality_op ID atom) // changed equality_op+ to equality_op
| '(' expr ')' -> ^('(' expr)
;
atom
: ID
| id_list
| Int
| Number
| String
| '*'
;
id_list
: '(' ID (',' ID)+ ')' -> ID+
| '(' Number (',' Number)* ')' -> Number+
| '(' String (',' String)* ')' -> String+
;
equality_op
: IS NOT -> IS_NOT // added
| NOT IN -> NOT_IN // added
| IN
| IS
| NOT
;
logical_op
: AND
| OR
;
IS : 'IS' | 'is'; // added
NOT : 'NOT' | 'not'; // added
IN : 'IN' | 'in'; // added
AND : 'AND' | 'and'; // added
OR : 'OR' | 'or'; // added
Number
: Int ('.' Digit*)?
;
ID
: ('a'..'z' | 'A'..'Z' | '_' | '.' | '-' | '*' | '/' | ':' | Digit)+
;
String
#after {
setText(getText().substring(1, getText().length()-1).replaceAll("\\\\(.)", "$1"));
}
: '"' (~('"' | '\\') | '\\' ('\\' | '"'))* '"'
| '\'' (~('\'' | '\\') | '\\' ('\\' | '\''))* '\''
;
Comment
: '//' ~('\r' | '\n')* {skip();}
| '/*' .* '*/' {skip();}
;
Space
: (' ' | '\t' | '\r' | '\n' | '\u000C') {skip();}
;
fragment Int
: '1'..'9' Digit*
| '0'
;
fragment Digit
: '0'..'9'
;
indexes
: ('[' expr ']')+ -> ^(INDEXES expr+)
;
which produces the following AST:
Also, lexer rules should always match at least 1 character (I've mentioned this before to you). Your lexer rule ID possibly matched 0 chars.

The problem is that equalityop+ will only have the value of the first match.
I see different workarounds: create specific rules if it is just for not or not in, create a subrules, or concatenate a variable like i do here:
equality_expr
: ID (full_op+=equality_op) + atom -> ^(full_op ID atom)
| '(' expr ')' -> ^('(' expr)
;
The following problem is different but gives my the idea:
Antlr AST generating (possible) madness

Remove extra symbol from the repetitive ANTLR rule

Consider the following simple grammar.
grammar test;
options {
language = Java;
output = AST;
}
//imaginary tokens
tokens{
}
parse
: declaration
;
declaration
: forall
;
forall
:'forall' '('rule1')' '[' (( '(' rule2 ')' '|' )* ) ']'
;
rule1
: INT
;
rule2
: ID
;
ID
: ('a'..'z' | 'A'..'Z'|'_')('a'..'z' | 'A'..'Z'|'0'..'9'|'_')*
;
INT
: ('0'..'9')+
;
WHITESPACE
: ('\t' | ' ' | '\r' | '\n' | '\u000C')+ {$channel = HIDDEN;}
;
and here is the input
forall (1) [(first) | (second) | (third) | (fourth) | (fifth) |]
The grammar works fine for the above input but I want to get rid of the extra pipe symbol (2nd last character in the input) from the input.
Any thoughts/ideas?

My antlr syntax is a bit rusty but you should try something like this:
forall
:'forall' '('rule1')' '[' ('(' rule2 ')' ('|' '(' rule2 ')' )* )? ']'
;
That is, instead of (r|)* write (r(|r)*)?. You can see how the latter allows for zero, one or many rules with pipes inbetween.

ANTLR replace tokens in a recursive manner

I have the following grammar:
rule: q=QualifiedName {System.out.println($q.text);};
QualifiedName
:
i=Identifier { $i.setText($i.text + "_");}
('[' (QualifiedName+ | Integer)? ']')*
;
Integer
: Digit Digit*
;
fragment
Digit
: '0'..'9'
;
fragment
Identifier
: ( '_'
| '$'
| ('a'..'z' | 'A'..'Z')
)
('a'..'z' | 'A'..'Z' | '0'..'9' | '_' | '$')*
;
and the code from Java:
ANTLRStringStream stream = new ANTLRStringStream("array1[array2[array3[index]]]");
TestLexer lexer = new TestLexer(stream);
CommonTokenStream tokens = new TokenRewriteStream(lexer);
TestParser parser = new TestParser(tokens);
try {
parser.rule();
} catch (RecognitionException e) {
e.printStackTrace();
}
For the input: array1[array2[array3[index]]], i want to modify each identifier. I was expecting to see the output: array1_[array_2[array3_[index_]]], but the output was the same as the input.
So the question is: why the setText() method doesn't work here?
EDIT:
I modified Bart's answer in the following way:
rule: q=qualifiedName {System.out.println($q.modified);};
qualifiedName returns [String modified]
:
Identifier
('[' (qualifiedName+ | Integer)? ']')*
{
$modified = $text + "_";
}
;
Identifier
: ( '_'
| '$'
| ('a'..'z' | 'A'..'Z')
)
('a'..'z' | 'A'..'Z' | '0'..'9' | '_' | '$')*
;
Integer
: Digit Digit*
;
fragment
Digit
: '0'..'9'
;
I want to modify each token matched by the rule qualifiedName. I tried the code above, and for the input array1[array2[array3[index]]] i was expecting to see the output array1[array2[array3[index_]_]_]_, but instead only the last token was modified: array1[array2[array3[index]]]_.
How can i solve this?

You can only use setText(...) once a token is created. You're recursively calling this token and setting some other text, which won't work. You'll need to create a parser rule out of QualifiedName instead of a lexer rule, and remove the fragment before Identifier.
rule: q=qualifiedName {System.out.println($q.text);};
qualifiedName
:
i=Identifier { $i.setText($i.text + "_");}
('[' (qualifiedName+ | Integer)? ']')*
;
Identifier
: ( '_'
| '$'
| ('a'..'z' | 'A'..'Z')
)
('a'..'z' | 'A'..'Z' | '0'..'9' | '_' | '$')*
;
Integer
: Digit Digit*
;
fragment
Digit
: '0'..'9'
;
Now, it will print: array1_[array2_[array3_[index_]]] on the console.
EDIT
I have no idea why you'd want to do that, but it seems you're simply trying to rewrite ] into ]_, which can be done in the same way as I showed above:
qualifiedName
:
Identifier
('[' (qualifiedName+ | Integer)? t=']' {$t.setText("]_");} )*
;