ASTMatchRecognizeHelper.java 文件源码

public static RowRegexExprRepeatDesc walkOptionalRepeat(EsperEPL2GrammarParser.MatchRecogPatternRepeatContext ctx, Map<Tree, ExprNode> astExprNodeMap) {
    if (ctx == null) {
        return null;
    }

    ExprNode e1 = ctx.e1 == null ? null : ASTExprHelper.exprCollectSubNodes(ctx.e1, 0, astExprNodeMap).get(0);
    ExprNode e2 = ctx.e2 == null ? null : ASTExprHelper.exprCollectSubNodes(ctx.e2, 0, astExprNodeMap).get(0);

    if (ctx.comma == null && ctx.e1 != null) {
        return new RowRegexExprRepeatDesc(null, null, e1);
    }

    if (e1 == null && e2 == null) {
        throw ASTWalkException.from("Invalid match-recognize quantifier '" + ctx.getText() + "', expecting an expression");
    }

    return new RowRegexExprRepeatDesc(e1, e2, null);
}