Question

我只是使用ANTLR4来编写一些语法。在我编写java代码输入数据后，ANTLR为我生成解析树。但是，在检查语法后，我只需要终端，我找不到任何方法只返回每个终端给我。语法如下：

grammar Expr;
prog: stat;
stat:   (createSQL | insertSQL) ';' stat*
        |(createSQL | insertSQL) ';'?;
createSQL: CREATE TABLE NAME  '(' att_def ')'
;
insertSQL: INSERT INTO NAME ('(' (att_names) ')')? VALUES '(' att_values ')' 
;
att_names: NAME ',' att_names
|  NAME
; 
att_values  : (NUM | str) (',' (NUM | str))*   
;
str  : '\'' .*? '\''
;
att_def : NAME ATTTYPE PRIMARYKEY 
| NAME ATTTYPE PRIMARYKEY ',' subatt_def
| NAME ATTTYPE  ',' att_def
| NAME ATTTYPE
;
subatt_def: NAME ATTTYPE ',' subatt_def
| NAME ATTTYPE
;
PRIMARYKEY: [Pp] [Rr] [Ii] [Mm] [Aa] [Rr] [Yy] ' ' [Kk] [Ee] [Yy]
;
ATTTYPE :  'varchar' '(' [1-3]INT ')' 
|  'varchar' '(' [1-9] ')' 
|  'varchar' '(' '40' ')'
|  'int'
;
INSERT: [iI] [nN] [sS] [eE] [rR] [tT];
INTO : [iI] [nN] [tT] [oO];
VALUES : [vV] [aA] [lL] [uU] [eE] [sS];
NUM  : [0-9]+;
INT :  [0-9];
CREATE: [cC] [rR] [eE] [aA] [tT] [eE];
TABLE: [tT] [aA] [bB] [lL] [eE];
NAME: [a-zA-Z]([a-z-A-z] | '_' | '-')*;
NEWLINE: ['\r'? '\n']->skip;
TAB :   [\t];

输入：

创建TABLE Person（person_id varchar（25）PRIMARY KEY，year int，age int）;
插入Person（person_id，year，age）值（＆＃39;我是super man_lin＆＃39;，1988,25）; java代码：

public class ANTLRDemo{
public static void main(String[] args) throws Exception{
    String inputFile = "t.expr";
    InputStream is = new FileInputStream(inputFile);
    ANTLRInputStream input = new ANTLRInputStream(is);
    ExprLexer lexer = new ExprLexer(input);
    CommonTokenStream tokens = new CommonTokenStream(lexer);
    ExprParser parser = new ExprParser(tokens);
    ParseTree tree = parser.prog();
    System.out.println(tree.toStringTree(parser));}}

有人可以帮助我吗？我只想得到一个包含所有终端的字符串数组，除了＆＃39;（＆＃39;，＆＃39;）＆＃39;，＆＃39;，＆＃39;。

Answer 1

分析树：

/** Return the combined text of all leaf nodes. Does not get any
 *  off-channel tokens (if any) so won't return whitespace and
 *  comments if they are sent to parser on hidden channel.
 */
String getText();

泰尔

如何使用ANTLR4获取终端

1 个答案: