/*
* Copyright 1999-2011 Alibaba Group Holding Ltd.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.alibaba.druid.sql.dialect.postgresql.parser;
import com.alibaba.druid.sql.ast.expr.SQLAggregateExpr;
import com.alibaba.druid.sql.dialect.postgresql.ast.PGAggregateExpr;
import com.alibaba.druid.sql.dialect.postgresql.ast.PGOrderBy;
import com.alibaba.druid.sql.dialect.postgresql.ast.expr.PGAnalytic;
import com.alibaba.druid.sql.parser.Lexer;
import com.alibaba.druid.sql.parser.SQLExprParser;
import com.alibaba.druid.sql.parser.Token;
public class PGExprParser extends SQLExprParser{
public PGExprParser(String sql) {
super(new PGLexer(sql));
this.lexer.nextToken();
}
public PGExprParser(Lexer lexer){
super(lexer);
}
protected SQLAggregateExpr parseAggregateExpr(String methodName) {
methodName = methodName.toUpperCase();
PGAggregateExpr aggregateExpr;
if (lexer.token() == Token.ALL) {
aggregateExpr = new PGAggregateExpr(methodName, SQLAggregateExpr.Option.ALL);
lexer.nextToken();
} else if (lexer.token() == Token.DISTINCT) {
aggregateExpr = new PGAggregateExpr(methodName, SQLAggregateExpr.Option.DISTINCT);
lexer.nextToken();
} else {
aggregateExpr = new PGAggregateExpr(methodName);
}
exprList(aggregateExpr.getArguments());
accept(Token.RPAREN);
if (lexer.token() == Token.OVER) {
lexer.nextToken();
PGAnalytic over = new PGAnalytic();
accept(Token.LPAREN);
if (identifierEquals("PARTITION")) {
lexer.nextToken();
accept(Token.BY);
if (lexer.token() == (Token.LPAREN)) {
lexer.nextToken();
exprList(over.getPartitionBy());
accept(Token.RPAREN);
} else {
exprList(over.getPartitionBy());
}
}
over.setOrderBy(parseOrderBy());
// if (over.getOrderBy() != null) {
// //TODO window
// }
accept(Token.RPAREN);
aggregateExpr.setOver(over);
}
return aggregateExpr;
}
@Override
public PGOrderBy parseOrderBy() {
if (lexer.token() == (Token.ORDER)) {
PGOrderBy orderBy = new PGOrderBy();
lexer.nextToken();
if (identifierEquals("SIBLINGS")) {
lexer.nextToken();
orderBy.setSibings(true);
}
accept(Token.BY);
orderBy.getItems().add(parseSelectOrderByItem());
while (lexer.token() == (Token.COMMA)) {
lexer.nextToken();
orderBy.getItems().add(parseSelectOrderByItem());
}
return orderBy;
}
return null;
}
}