private static WhereCondition GenerateStatementNode(SelectSQLParser.WhereStmtContext whereStmt)
{
var andOr = whereStmt.AND_OR();
var subWhereStmts = whereStmt.whereStmt();
var whereCondition = whereStmt.whereCondition();
if (whereCondition != null && !whereCondition.IsEmpty) //普通单项where条件
{
return(GenerateConditionNode(whereCondition));
}
if (subWhereStmts == null || subWhereStmts.Length < 2)
{
throw new MissingWhereConditionException();
}
//父节点，非单项where条件
var stmtNode = new WhereCondition(WhereConditionNodeType.Statement);
var leftWhereStmt = subWhereStmts.First();
var rightWhereStmt = subWhereStmts.Last();
stmtNode.Statement_LeftNode = GenerateStatementNode(leftWhereStmt);
stmtNode.Statement_Operator = andOr.GetText();
stmtNode.Statement_RightNode = GenerateStatementNode(rightWhereStmt);
return(stmtNode);
}
/// <summary>
/// Visit a parse tree produced by <see cref="SelectSQLParser.whereStmt"/>.
/// <para>
/// The default implementation returns the result of calling <see cref="AbstractParseTreeVisitor{Result}.VisitChildren(IRuleNode)"/>
/// on <paramref name="context"/>.
/// </para>
/// </summary>
/// <param name="context">The parse tree.</param>
/// <return>The visitor result.</return>
public virtual Result VisitWhereStmt([NotNull] SelectSQLParser.WhereStmtContext context)
{
return(VisitChildren(context));
}
/// <summary>
/// Exit a parse tree produced by <see cref="SelectSQLParser.whereStmt"/>.
/// <para>The default implementation does nothing.</para>
/// </summary>
/// <param name="context">The parse tree.</param>
public virtual void ExitWhereStmt([NotNull] SelectSQLParser.WhereStmtContext context)
{
}
