如何使用Java在ANTLR中获取SQL Where节点表达式

grammar SQL;

...

whereExpression : 'WHERE' expression;
expression : logicalExpression;
logicalExpression : comparisonExpression (logicalOperator comparisonExpression)*;
comparisonExpression : column comparisonOperator value;
column : ID;
comparisonOperator : '=' | '<>' | '<' | '>' | '<=' | '>=';
value : STRING | NUMBER;

...

import org.antlr.v4.runtime.*;
import org.antlr.v4.runtime.tree.*;

public class SQLParserExample {
    public static void main(String[] args) throws Exception {
        String sql = "SELECT * FROM table WHERE column = 'value'";
        
        // 创建ANTLR输入流
        ANTLRInputStream input = new ANTLRInputStream(sql);
        
        // 创建词法分析器
        SQLLexer lexer = new SQLLexer(input);
        
        // 创建词法记号流
        CommonTokenStream tokens = new CommonTokenStream(lexer);
        
        // 创建语法解析器
        SQLParser parser = new SQLParser(tokens);
        
        // 解析语法规则
        ParseTree tree = parser.whereExpression();
        
        // 创建遍历器
        ParseTreeWalker walker = new ParseTreeWalker();
        
        // 创建监听器
        SQLListener listener = new SQLBaseListener() {
            @Override
            public void enterComparisonExpression(SQLParser.ComparisonExpressionContext ctx) {
                String column = ctx.column().getText();
                String operator = ctx.comparisonOperator().getText();
                String value = ctx.value().getText();
                
                System.out.println("Column: " + column);
                System.out.println("Operator: " + operator);
                System.out.println("Value: " + value);
            }
        };
        
        // 遍历语法树
        walker.walk(listener, tree);
    }
}