Accessing nested parse trees Java Antlr

Question

I am relatively new to ANTLR and was trying to integrate my grammar into a java program. This is my .g4 file.

/*
 * The MIT License (MIT)
 *
 * Copyright (c) 2014 by Bart Kiers
 *
 * Permission is hereby granted, free of charge, to any person
 * obtaining a copy of this software and associated documentation
 * files (the "Software"), to deal in the Software without
 * restriction, including without limitation the rights to use,
 * copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following
 * conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 *
 * Project      : sqlite-parser; an ANTLR4 grammar for SQLite
 *                https://github.com/bkiers/sqlite-parser
 * Developed by : Bart Kiers, [email protected]
 */
grammar SQLite;

parse
 : ( sql_stmt_list | error )* EOF
 ;

error
 : UNEXPECTED_CHAR 
   { 
     throw new RuntimeException("UNEXPECTED_CHAR=" + $UNEXPECTED_CHAR.text); 
   }
 ;

sql_stmt_list
 : ';'* sql_stmt ( ';'+ sql_stmt )* ';'*
 ;

sql_stmt
 : ( K_EXPLAIN ( K_QUERY K_PLAN )? )? ( alter_table_stmt
                                      | analyze_stmt
                                      | attach_stmt
                                      | begin_stmt
                                      | commit_stmt
                                      | compound_select_stmt
                                      | create_index_stmt
                                      | create_table_stmt
                                      | create_trigger_stmt
                                      | create_view_stmt
                                      | create_virtual_table_stmt
                                      | delete_stmt
                                      | delete_stmt_limited
                                      | detach_stmt
                                      | drop_index_stmt
                                      | drop_table_stmt
                                      | drop_trigger_stmt
                                      | drop_view_stmt
                                      | factored_select_stmt
                                      | insert_stmt
                                      | pragma_stmt
                                      | reindex_stmt
                                      | release_stmt
                                      | rollback_stmt
                                      | savepoint_stmt
                                      | simple_select_stmt
                                      | select_stmt
                                      | update_stmt
                                      | update_stmt_limited
                                      | vacuum_stmt )
 ;

alter_table_stmt
 : K_ALTER K_TABLE ( database_name '.' )? table_name
   ( K_RENAME K_TO new_table_name
   | K_ADD K_COLUMN? column_def
   )
 ;

analyze_stmt
 : K_ANALYZE ( database_name | table_or_index_name | database_name '.' table_or_index_name )?
 ;

attach_stmt
 : K_ATTACH K_DATABASE? expr K_AS database_name
 ;

begin_stmt
 : K_BEGIN ( K_DEFERRED | K_IMMEDIATE | K_EXCLUSIVE )? ( K_TRANSACTION transaction_name? )?
 ;

commit_stmt
 : ( K_COMMIT | K_END ) ( K_TRANSACTION transaction_name? )?
 ;

compound_select_stmt
 : with_clause?
   select_core ( ( K_UNION K_ALL? | K_INTERSECT | K_EXCEPT ) select_core )+
   ( K_ORDER K_BY ordering_term ( ',' ordering_term )* )?
   ( K_LIMIT expr ( ( K_OFFSET | ',' ) expr )? )?
 ;

create_index_stmt
 : K_CREATE K_UNIQUE? K_INDEX ( K_IF K_NOT K_EXISTS )?
   ( database_name '.' )? index_name K_ON table_name '(' indexed_column ( ',' indexed_column )* ')'
   ( K_WHERE expr )?
 ;

create_table_stmt
 : K_CREATE ( K_TEMP | K_TEMPORARY )? K_TABLE ( K_IF K_NOT K_EXISTS )?
   ( database_name '.' )? table_name
   ( '(' column_def ( ',' column_def )*? ( ',' table_constraint )* ')' ( K_WITHOUT IDENTIFIER )?
   | K_AS select_stmt 
   )
 ;

create_trigger_stmt
 : K_CREATE ( K_TEMP | K_TEMPORARY )? K_TRIGGER ( K_IF K_NOT K_EXISTS )?
   ( database_name '.' )? trigger_name ( K_BEFORE  | K_AFTER | K_INSTEAD K_OF )? 
   ( K_DELETE | K_INSERT | K_UPDATE ( K_OF column_name ( ',' column_name )* )? ) K_ON ( database_name '.' )? table_name
   ( K_FOR K_EACH K_ROW )? ( K_WHEN expr )?
   K_BEGIN ( ( update_stmt | insert_stmt | delete_stmt | select_stmt ) ';' )+ K_END
 ;

create_view_stmt
 : K_CREATE ( K_TEMP | K_TEMPORARY )? K_VIEW ( K_IF K_NOT K_EXISTS )?
   ( database_name '.' )? view_name K_AS select_stmt
 ;

create_virtual_table_stmt
 : K_CREATE K_VIRTUAL K_TABLE ( K_IF K_NOT K_EXISTS )?
   ( database_name '.' )? table_name
   K_USING module_name ( '(' module_argument ( ',' module_argument )* ')' )?
 ;

delete_stmt
 : with_clause? K_DELETE K_FROM qualified_table_name 
   ( K_WHERE expr )?
 ;

delete_stmt_limited
 : with_clause? K_DELETE K_FROM qualified_table_name 
   ( K_WHERE expr )?
   ( ( K_ORDER K_BY ordering_term ( ',' ordering_term )* )?
     K_LIMIT expr ( ( K_OFFSET | ',' ) expr )?
   )?
 ;

detach_stmt
 : K_DETACH K_DATABASE? database_name
 ;

drop_index_stmt
 : K_DROP K_INDEX ( K_IF K_EXISTS )? ( database_name '.' )? index_name
 ;

drop_table_stmt
 : K_DROP K_TABLE ( K_IF K_EXISTS )? ( database_name '.' )? table_name
 ;

drop_trigger_stmt
 : K_DROP K_TRIGGER ( K_IF K_EXISTS )? ( database_name '.' )? trigger_name
 ;

drop_view_stmt
 : K_DROP K_VIEW ( K_IF K_EXISTS )? ( database_name '.' )? view_name
 ;

factored_select_stmt
 : with_clause?
   select_core ( compound_operator select_core )*
   ( K_ORDER K_BY ordering_term ( ',' ordering_term )* )?
   ( K_LIMIT expr ( ( K_OFFSET | ',' ) expr )? )?
 ;

insert_stmt
 : with_clause? ( K_INSERT 
                | K_REPLACE
                | K_INSERT K_OR K_REPLACE
                | K_INSERT K_OR K_ROLLBACK
                | K_INSERT K_OR K_ABORT
                | K_INSERT K_OR K_FAIL
                | K_INSERT K_OR K_IGNORE ) K_INTO
   ( database_name '.' )? table_name ( '(' column_name ( ',' column_name )* ')' )?
   ( K_VALUES '(' expr ( ',' expr )* ')' ( ',' '(' expr ( ',' expr )* ')' )*
   | select_stmt
   | K_DEFAULT K_VALUES
   )
 ;

pragma_stmt
 : K_PRAGMA ( database_name '.' )? pragma_name ( '=' pragma_value
                                               | '(' pragma_value ')' )?
 ;

reindex_stmt
 : K_REINDEX ( collation_name
             | ( database_name '.' )? ( table_name | index_name )
             )?
 ;

release_stmt
 : K_RELEASE K_SAVEPOINT? savepoint_name
 ;

rollback_stmt
 : K_ROLLBACK ( K_TRANSACTION transaction_name? )? ( K_TO K_SAVEPOINT? savepoint_name )?
 ;

savepoint_stmt
 : K_SAVEPOINT savepoint_name
 ;

simple_select_stmt
 : with_clause?
   select_core ( K_ORDER K_BY ordering_term ( ',' ordering_term )* )?
   ( K_LIMIT expr ( ( K_OFFSET | ',' ) expr )? )?
 ;

select_stmt
 : with_clause?
   select_or_values ( compound_operator select_or_values )*
   ( K_ORDER K_BY ordering_term ( ',' ordering_term )* )?
   ( K_LIMIT  limit | (expr ( ( K_OFFSET | ',' ) expr )?) )? 
   ( K_SKIP skip)?
 ;//Skip and Contains will come here added

select_or_values
 : K_SELECT ( K_DISTINCT | K_ALL )? result_column ( ',' result_column )* (',' K_OVER'(' K_PARTITION K_BY (K_WITHIN K_DISTANCE)? '('partition_term')' ',' K_COLLECTIVE'(' (K_SKIP skip ( K_LIMIT limit)?')' (K_HAVING expr K_ORDER K_BY ordering_term ( ',' ordering_term )*)?)?')')?
   ( K_FROM ( table_or_subquery ( ',' table_or_subquery )* | join_clause ) )?
   ( K_WHERE expr )?
   ( K_COLLECTIVE '(' K_ORDER K_BY ordering_term  (( K_LIMIT limit K_SKIP skip)?|(K_SKIP skip K_LIMIT limit)?) ')')?
   ( K_GROUP K_BY expr ( (',')? K_COLLECTIVE '(' K_ORDER K_BY ordering_term(',' ordering_term )* ( (K_LIMIT limit K_SKIP skip)?| (K_SKIP skip K_LIMIT limit)?)')')? ( ',' expr )* ( K_HAVING expr )? )?
 | K_VALUES '(' expr ( ',' expr )* ')' ( ',' '(' expr ( ',' expr )* ')' )*
 ;
//Partition by added here
partition_term
 : any_name '.' any_name ',' any_name
 ;

 //Partition by and within distance term

update_stmt
 : with_clause? K_UPDATE ( K_OR K_ROLLBACK
                         | K_OR K_ABORT
                         | K_OR K_REPLACE
                         | K_OR K_FAIL
                         | K_OR K_IGNORE )? qualified_table_name
   K_SET column_name '=' expr ( ',' column_name '=' expr )* ( K_WHERE expr )?
 ;

update_stmt_limited
 : with_clause? K_UPDATE ( K_OR K_ROLLBACK
                         | K_OR K_ABORT
                         | K_OR K_REPLACE
                         | K_OR K_FAIL
                         | K_OR K_IGNORE )? qualified_table_name
   K_SET column_name '=' expr ( ',' column_name '=' expr )* ( K_WHERE expr )?
   ( ( K_ORDER K_BY ordering_term ( ',' ordering_term )* )?
     K_LIMIT expr ( ( K_OFFSET | ',' ) expr )? 
   )?
 ;

vacuum_stmt
 : K_VACUUM
 ;

column_def
 : column_name type_name? column_constraint*
 ;

type_name
 : name+? ( '(' signed_number ')'
         | '(' signed_number ',' signed_number ')' )?
 ;

column_constraint
 : ( K_CONSTRAINT name )?
   ( K_PRIMARY K_KEY ( K_ASC | K_DESC )? conflict_clause K_AUTOINCREMENT?
   | K_NOT? K_NULL conflict_clause
   | K_UNIQUE conflict_clause
   | K_CHECK '(' expr ')'
   | K_DEFAULT (signed_number | literal_value | '(' expr ')')
   | K_COLLATE collation_name
   | foreign_key_clause
   )
 ;

conflict_clause
 : ( K_ON K_CONFLICT ( K_ROLLBACK
                     | K_ABORT
                     | K_FAIL
                     | K_IGNORE
                     | K_REPLACE
                     )
   )?
 ;

//added limit here

limit
 :(K_CONTAINS (contain)?)?
//(K_CONTAINS ( '(' K_COLLECT '('(file_read)')' ',' '"'any_name'"' ')')?)?
//(K_CONTAINS (contain)?)?
 ;
contain
 : '(' K_COLLECT '('(file_read)')' ',' (any_name)? (file_read)?')'((file_read)? | (any_name)?)
 //'(' K_COLLECT '('(file_read)')' ',' (any_name)? ')'')'
 ;

skip
 : (K_CONTAINS ( contain )?)?
 //(K_CONTAINS ( '(' K_COLLECT '('(file_read)')' ',' ('"'(any_name)'"' )? (file_read)? )?)?')'
 ;

/*
    SQLite understands the following binary operators, in order from highest to
    lowest precedence:

    ||
    *    /    %
    +    -
    <<   >>   &    |
    <    <=   >    >=
    =    ==   !=   <>   IS   IS NOT   IN   LIKE   GLOB   MATCH   REGEXP
    AND
    OR
*/
//added
file_name
 : any_name '.' any_name
 ;
read_name
 : '"' any_name (',' any_name)* '"'
 ;

//initial adition of Overlap    
expr
 : literal_value
 | BIND_PARAMETER
 | file_read
 | read_name
 | function_name '(' ( K_DISTINCT? expr ( ',' expr )* | '*' )? ')'
 | ( ( database_name '.' )? table_name '.' )? column_name
 | unary_operator expr
 | expr '||' expr
 | expr ( '*' | '/' | '%' ) expr
 | expr ( '+' | '-' ) expr
 | expr ( '<<' | '>>' | '&' | '|' ) expr
 | expr ( '<' | '<=' | '>' | '>=' ) expr
 | expr ( '=' | '==' | '!=' | '<>' ) expr
 | expr K_AND expr
 | expr K_OR expr
 | '(' expr ')'
 | K_CAST '(' expr K_AS type_name ')'
 | expr K_COLLATE collation_name
 | expr K_NOT? ( K_LIKE | K_GLOB | K_REGEXP | K_MATCH ) expr ( K_ESCAPE expr )?
 | expr ( K_ISNULL | K_NOTNULL | K_NOT K_NULL )
 | expr K_IS K_NOT? expr
 | expr K_NOT? K_BETWEEN expr K_AND expr
 | expr K_NOT? K_IN ( '(' ( select_stmt
                          | expr ( ',' expr )*
                          )? 
                      ')'
                    | ( database_name '.' )? table_name )
 | ( ( K_NOT )? K_EXISTS )? '(' select_stmt ')'
 | K_CASE expr? ( K_WHEN expr K_THEN expr )+ ( K_ELSE expr )? K_END
 | raise_function
 ;

foreign_key_clause
 : K_REFERENCES foreign_table ( '(' column_name ( ',' column_name )* ')' )?
   ( ( K_ON ( K_DELETE | K_UPDATE ) ( K_SET K_NULL
                                    | K_SET K_DEFAULT
                                    | K_CASCADE
                                    | K_RESTRICT
                                    | K_NO K_ACTION )
     | K_MATCH name
     ) 
   )*
   ( K_NOT? K_DEFERRABLE ( K_INITIALLY K_DEFERRED | K_INITIALLY K_IMMEDIATE )? )?
 ;

raise_function
 : K_RAISE '(' ( K_IGNORE 
               | ( K_ROLLBACK | K_ABORT | K_FAIL ) ',' error_message )
           ')'
 ;

indexed_column
 : column_name ( K_COLLATE collation_name )? ( K_ASC | K_DESC )?
 ;

table_constraint
 : ( K_CONSTRAINT name )?
   ( ( K_PRIMARY K_KEY | K_UNIQUE ) '(' indexed_column ( ',' indexed_column )* ')' conflict_clause
   | K_CHECK '(' expr ')'
   | K_FOREIGN K_KEY '(' column_name ( ',' column_name )* ')' foreign_key_clause
   )
 ;

with_clause
 : K_WITH K_RECURSIVE? common_table_expression ( ',' common_table_expression )*
 ;

qualified_table_name
 : ( database_name '.' )? table_name ( K_INDEXED K_BY index_name
                                     | K_NOT K_INDEXED )?
 ;

ordering_term
 : expr ( K_COLLATE collation_name )? ( K_ASC | K_DESC )?
 | expr '+' expr
 ;

pragma_value
 : signed_number
 | name
 | STRING_LITERAL
 ;

common_table_expression
 : table_name ( '(' column_name ( ',' column_name )* ')' )? K_AS '(' select_stmt ')'
 ;

result_column
 : '*'
 | table_name '.' '*'
 | expr ( K_AS? column_alias )?
 ;

table_or_subquery
 : ( schema_name '.' )? table_name ( K_AS? table_alias )?
   ( K_INDEXED K_BY index_name
   | K_NOT K_INDEXED )?
 | ( schema_name '.' )? table_function_name '(' ( expr ( ',' expr )* )? ')' ( K_AS? table_alias )?
 | '(' ( table_or_subquery ( ',' table_or_subquery )*
       | join_clause )
   ')'
 | '(' select_stmt ')' ( K_AS? table_alias )?
 ;

join_clause
 : table_or_subquery ( join_operator table_or_subquery join_constraint )*
 ;

join_operator
 : ','
 | K_NATURAL? ( K_LEFT K_OUTER? | K_INNER | K_CROSS )? K_JOIN
 ;

join_constraint
 : ( K_ON expr
   | K_USING '(' column_name ( ',' column_name )* ')' )?
 ;

select_core
 : K_SELECT ( K_DISTINCT | K_ALL )? result_column ( ',' result_column )*
   ( K_FROM ( table_or_subquery ( ',' table_or_subquery )* | join_clause ) )?
   ( K_WHERE expr )?
   ( K_GROUP K_BY expr ( ',' expr )* ( K_HAVING expr )? )?
 | K_VALUES '(' expr ( ',' expr )* ')' ( ',' '(' expr ( ',' expr )* ')' )*
 ;

compound_operator
 : K_UNION
 | K_UNION K_ALL
 | K_INTERSECT
 | K_EXCEPT
 ;

signed_number
 : ( '+' | '-' )? NUMERIC_LITERAL
 ;

literal_value
 : NUMERIC_LITERAL
 | STRING_LITERAL
 | BLOB_LITERAL
 | K_NULL
 | K_CURRENT_TIME
 | K_CURRENT_DATE
 | K_CURRENT_TIMESTAMP
 ;

unary_operator
 : '-'
 | '+'
 | '~'
 | K_NOT
 ;

error_message
 : STRING_LITERAL
 ;

module_argument // TODO check what exactly is permitted here
 : expr
 | column_def
 ;

column_alias
 : IDENTIFIER
 | STRING_LITERAL
 ;

keyword
 : K_ABORT
 | K_ACTION
 | K_ADD
 | K_AFTER
 | K_ALL
 | K_ALTER
 | K_ANALYZE
 | K_AND
 | K_AS
 | K_ASC
 | K_ATTACH
 | K_AUTOINCREMENT
 | K_BEFORE
 | K_BEGIN
 | K_BETWEEN
 | K_BY
 | K_CASCADE
 | K_CASE
 | K_CAST
 | K_CHECK
 | K_COLLATE
 | K_COLUMN
 | K_COMMIT
 | K_CONFLICT
 | K_CONSTRAINT
 | K_CREATE
 | K_CROSS
 | K_CURRENT_DATE
 | K_CURRENT_TIME
 | K_CURRENT_TIMESTAMP
 | K_DATABASE
 | K_DEFAULT
 | K_DEFERRABLE
 | K_DEFERRED
 | K_DELETE
 | K_DESC
 | K_DETACH
 | K_DISTINCT
 | K_DROP
 | K_EACH
 | K_ELSE
 | K_END
 | K_ESCAPE
 | K_EXCEPT
 | K_EXCLUSIVE
 | K_EXISTS
 | K_EXPLAIN
 | K_FAIL
 | K_FOR
 | K_FOREIGN
 | K_FROM
 | K_FULL
 | K_GLOB
 | K_GROUP
 | K_HAVING
 | K_IF
 | K_IGNORE
 | K_IMMEDIATE
 | K_IN
 | K_INDEX
 | K_INDEXED
 | K_INITIALLY
 | K_INNER
 | K_INSERT
 | K_INSTEAD
 | K_INTERSECT
 | K_INTO
 | K_IS
 | K_ISNULL
 | K_JOIN
 | K_KEY
 | K_LEFT
 | K_LIKE
 | K_LIMIT
 | K_MATCH
 | K_NATURAL
 | K_NO
 | K_NOT
 | K_NOTNULL
 | K_NULL
 | K_OF
 | K_OFFSET
 | K_ON
 | K_OR
 | K_ORDER
 | K_OUTER
 | K_PLAN
 | K_PRAGMA
 | K_PRIMARY
 | K_QUERY
 | K_RAISE
 | K_RECURSIVE
 | K_REFERENCES
 | K_REGEXP
 | K_REINDEX
 | K_RELEASE
 | K_RENAME
 | K_REPLACE
 | K_RESTRICT
 | K_RIGHT
 | K_ROLLBACK
 | K_ROW
 | K_SAVEPOINT
 | K_SELECT
 | K_SET
 | K_TABLE
 | K_TEMP
 | K_TEMPORARY
 | K_THEN
 | K_TO
 | K_TRANSACTION
 | K_TRIGGER
 | K_UNION
 | K_UNIQUE
 | K_UPDATE
 | K_USING
 | K_VACUUM
 | K_VALUES
 | K_VIEW
 | K_VIRTUAL
 | K_WHEN
 | K_WHERE
 | K_WITH
 | K_WITHOUT
 | K_PARTITION
 | K_SKIP 
 | K_OVER
 | K_COLLECTIVE
 | K_WITHIN
 | K_DISTANCE
 | K_CONTAINS
 | K_COLLECT
 | K_OVERLAP
 ;

// TODO check all names below

name
 : any_name
 ;

function_name
 : any_name
 ;

database_name
 : any_name
 ;

schema_name
 : any_name
 ;

table_function_name
 : any_name
 ;

table_name 
 : any_name
 ;

table_or_index_name 
 : any_name
 ;

new_table_name 
 : any_name
 ;

column_name 
 : any_name
 ;

collation_name 
 : any_name
 ;

foreign_table 
 : any_name
 ;

index_name 
 : any_name
 ;

trigger_name
 : any_name
 ;

view_name 
 : any_name
 ;

module_name 
 : any_name
 ;

pragma_name 
 : any_name
 ;

savepoint_name 
 : any_name
 ;

table_alias
 : IDENTIFIER
 | STRING_LITERAL
 | '(' table_alias ')'
 ;

transaction_name
 : any_name
 ;

file_read
 : any_name '.' any_name
 ;
//added
inner_loop
 : IDENTIFIER 
 | inner_loop ',' inner_loop
 | any_name '.' any_name ',' any_name
 ;
any_name
 : IDENTIFIER 
 | keyword
 | STRING_LITERAL
 | '(' any_name ')'
 | any_name '.' any_name
 | '"'any_name'"'
 ;

//added
file_splitter
 : IDENTIFIER
 | keyword
 |STRING_LITERAL
 | file_splitter ','
 | ',' file_splitter ','
 | ',' file_splitter
 ;

SCOL : ';';
DOT : '.';
OPEN_PAR : '(';
CLOSE_PAR : ')';
COMMA : ',';
ASSIGN : '=';
STAR : '*';
PLUS : '+';
MINUS : '-';
TILDE : '~';
PIPE2 : '||';
DIV : '/';
MOD : '%';
LT2 : '<<';
GT2 : '>>';
AMP : '&';
PIPE : '|';
LT : '<';
LT_EQ : '<=';
GT : '>';
GT_EQ : '>=';
EQ : '==';
NOT_EQ1 : '!=';
NOT_EQ2 : '<>';

// http://www.sqlite.org/lang_keywords.html
K_ABORT : A B O R T;
K_ACTION : A C T I O N;
K_ADD : A D D;
K_AFTER : A F T E R;
K_ALL : A L L;
K_ALTER : A L T E R;
K_ANALYZE : A N A L Y Z E;
K_AND : A N D;
K_AS : A S;
K_ASC : A S C;
K_ATTACH : A T T A C H;
K_AUTOINCREMENT : A U T O I N C R E M E N T;
K_BEFORE : B E F O R E;
K_BEGIN : B E G I N;
K_BETWEEN : B E T W E E N;
K_BY : B Y;
K_CASCADE : C A S C A D E;
K_CASE : C A S E;
K_CAST : C A S T;
K_CHECK : C H E C K;
K_COLLATE : C O L L A T E;
K_COLUMN : C O L U M N;
K_COMMIT : C O M M I T;
K_CONFLICT : C O N F L I C T;
K_CONSTRAINT : C O N S T R A I N T;
K_CREATE : C R E A T E;
K_CROSS : C R O S S;
K_CURRENT_DATE : C U R R E N T '_' D A T E;
K_CURRENT_TIME : C U R R E N T '_' T I M E;
K_CURRENT_TIMESTAMP : C U R R E N T '_' T I M E S T A M P;
K_DATABASE : D A T A B A S E;
K_DEFAULT : D E F A U L T;
K_DEFERRABLE : D E F E R R A B L E;
K_DEFERRED : D E F E R R E D;
K_DELETE : D E L E T E;
K_DESC : D E S C;
K_DETACH : D E T A C H;
K_DISTINCT : D I S T I N C T;
K_DROP : D R O P;
K_EACH : E A C H;
K_ELSE : E L S E;
K_END : E N D;
K_ESCAPE : E S C A P E;
K_EXCEPT : E X C E P T;
K_EXCLUSIVE : E X C L U S I V E;
K_EXISTS : E X I S T S;
K_EXPLAIN : E X P L A I N;
K_FAIL : F A I L;
K_FOR : F O R;
K_FOREIGN : F O R E I G N;
K_FROM : F R O M;
K_FULL : F U L L;
K_GLOB : G L O B;
K_GROUP : G R O U P;
K_HAVING : H A V I N G;
K_IF : I F;
K_IGNORE : I G N O R E;
K_IMMEDIATE : I M M E D I A T E;
K_IN : I N;
K_INDEX : I N D E X;
K_INDEXED : I N D E X E D;
K_INITIALLY : I N I T I A L L Y;
K_INNER : I N N E R;
K_INSERT : I N S E R T;
K_INSTEAD : I N S T E A D;
K_INTERSECT : I N T E R S E C T;
K_INTO : I N T O;
K_IS : I S;
K_ISNULL : I S N U L L;
K_JOIN : J O I N;
K_KEY : K E Y;
K_LEFT : L E F T;
K_LIKE : L I K E;
K_LIMIT : L I M I T;
K_MATCH : M A T C H;
K_NATURAL : N A T U R A L;
K_NO : N O;
K_NOT : N O T;
K_NOTNULL : N O T N U L L;
K_NULL : N U L L;
K_OF : O F;
K_OFFSET : O F F S E T;
K_ON : O N;
K_OR : O R;
K_ORDER : O R D E R;
K_OUTER : O U T E R;
K_PLAN : P L A N;
K_PRAGMA : P R A G M A;
K_PRIMARY : P R I M A R Y;
K_QUERY : Q U E R Y;
K_RAISE : R A I S E;
K_RECURSIVE : R E C U R S I V E;
K_REFERENCES : R E F E R E N C E S;
K_REGEXP : R E G E X P;
K_REINDEX : R E I N D E X;
K_RELEASE : R E L E A S E;
K_RENAME : R E N A M E;
K_REPLACE : R E P L A C E;
K_RESTRICT : R E S T R I C T;
K_RIGHT : R I G H T;
K_ROLLBACK : R O L L B A C K;
K_ROW : R O W;
K_SAVEPOINT : S A V E P O I N T;
K_SELECT : S E L E C T;
K_SET : S E T;
K_TABLE : T A B L E;
K_TEMP : T E M P;
K_TEMPORARY : T E M P O R A R Y;
K_THEN : T H E N;
K_TO : T O;
K_TRANSACTION : T R A N S A C T I O N;
K_TRIGGER : T R I G G E R;
K_UNION : U N I O N;
K_UNIQUE : U N I Q U E;
K_UPDATE : U P D A T E;
K_USING : U S I N G;
K_VACUUM : V A C U U M;
K_VALUES : V A L U E S;
K_VIEW : V I E W;
K_VIRTUAL : V I R T U A L;
K_WHEN : W H E N;
K_WHERE : W H E R E;
K_WITH : W I T H;
K_WITHOUT : W I T H O U T; //My additions
K_PARTITION : P A R T I T I O N;
K_SKIP : S K I P;
K_OVER : O V E R;
K_COLLECTIVE : C O L L E C T I V E;
K_WITHIN : W I T H I N;
K_DISTANCE : D I S T A N C E;
K_CONTAINS : C O N T A I N S;
K_COLLECT : C O L L E C T;
K_OVERLAP : O V E R L A P;
//added

IDENTIFIER
 : '"' (~'"' | '""')* '"'
 | '`' (~'`' | '``')* '`'
 | '[' ~']'* ']'
 | [a-zA-Z_] [a-zA-Z_0-9]* // TODO check: needs more chars in set
 | [a-zA-Z_0-9]* //added
 ;

NUMERIC_LITERAL
 : DIGIT+ ( '.' DIGIT* )? ( E [-+]? DIGIT+ )?
 | '.' DIGIT+ ( E [-+]? DIGIT+ )?
 ;

BIND_PARAMETER
 : '?' DIGIT*
 | [:@$] IDENTIFIER
 ;

STRING_LITERAL
 : '\'' ( ~'\'' | '\'\'' )* '\''
 ;

BLOB_LITERAL
 : X STRING_LITERAL
 ;

SINGLE_LINE_COMMENT
 : '--' ~[\r\n]* -> channel(HIDDEN)
 ;

MULTILINE_COMMENT
 : '/*' .*? ( '*/' | EOF ) -> channel(HIDDEN)
 ;

SPACES
 : [ \u000B\t\r\n] -> channel(HIDDEN)
 ;

UNEXPECTED_CHAR
 : .
 ;

fragment DIGIT : [0-9];

fragment A : [aA];
fragment B : [bB];
fragment C : [cC];
fragment D : [dD];
fragment E : [eE];
fragment F : [fF];
fragment G : [gG];
fragment H : [hH];
fragment I : [iI];
fragment J : [jJ];
fragment K : [kK];
fragment L : [lL];
fragment M : [mM];
fragment N : [nN];
fragment O : [oO];
fragment P : [pP];
fragment Q : [qQ];
fragment R : [rR];
fragment S : [sS];
fragment T : [tT];
fragment U : [uU];
fragment V : [vV];
fragment W : [wW];
fragment X : [xX];
fragment Y : [yY];
fragment Z : [zZ];

This is the program I have to only access the first level of the outputted parse tree:-

//package nl.bigo.sqliteparser;

import org.antlr.v4.runtime.ANTLRInputStream;
import org.antlr.v4.runtime.CommonTokenStream;
import org.antlr.v4.runtime.misc.NotNull;
import org.antlr.v4.runtime.tree.ParseTree;
import org.antlr.v4.runtime.tree.ParseTreeWalker;
import java.util.ArrayList;
import java.util.List;

public class Main {

    public static void main(String[] args) throws Exception {

        // The list that will hold our function names.
        final List<String> functionNames = new ArrayList<String>();

        // The select-statement to be parsed.
        String sql = "SELECT log AS x FROM t1 \n" +
                "GROUP BY x\n" +
                "HAVING count(*) >= 4 \n" +
                "ORDER BY max(n) + 0 \n";

        // Create a lexer and parser for the input.
        SQLiteLexer lexer = new SQLiteLexer(new ANTLRInputStream(sql));
        SQLiteParser parser = new SQLiteParser(new CommonTokenStream(lexer));

        // Invoke the `select_stmt` production.
        ParseTree tree = parser.select_stmt(); //selects the parse tree

        // Walk the `select_stmt` production and listen when the parser
        // enters the `expr` production.
        ParseTreeWalker.DEFAULT.walk(new SQLiteBaseListener(){
            @Override
            public void enterExpr(@NotNull SQLiteParser.ExprContext ctx) {
                // Check if the expression is a function call.
                if (ctx.function_name() != null) {
                    // Yes, it was a function call: add the name of the function
                    // to out list.
                    functionNames.add(ctx.function_name().getText());
                }
            }
        }, tree);

        ParseTreeWalker.DEFAULT.walk(new SQLiteBaseListener() { 
        //@Override
        public void enterExpr(@NotNull SQLiteParser.Ordering_termContext ctx){
            if(ctx.expr() !=null)
            {
                //what to add here?

            }
        }
    }, tree);
    }
}

How do I do a parse tree traversal? I was trying to access the nested structure inside the expr rule. for example if expr had another expr inside it, how would the access work in java? AnotherQuestion I had was that if I had to access the third level in the ordered_term nested tree would it still be possible? If so how?

Raven Raven · Accepted Answer · 2017-03-22T07:04:01

Each ParserRuleContext object that gets passed into the methods in your ParseTreeWalker has a method for retrieving it's children (which then in turn have methods for getting their children and so on).
So basically you just need to know at which index you have to search for the respective element.

Accessing nested parse trees Java Antlr

1 Answers